Protein Kinases, catalytic domain; The protein kinase superfamily is mainly composed of the catalytic domains of serine/threonine-specific and tyrosine-specific protein kinases. It also includes RIO kinases, which are atypical serine protein kinases, aminoglycoside phosphotransferases, and choline kinases. These proteins catalyze the transfer of the gamma-phosphoryl group from ATP to hydroxyl groups in specific substrates such as serine, threonine, or tyrosine residues of proteins.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 148 EQLRGCRVVGVIEKrdlavlprlvsnslpqVQLVQDPATGGTFVVKSLPRCHMVSRERLTIIPHGVPYMTKLLRYFVSED 227
Cdd:cd05576     1 EELKAFRVLGVIDK----------------VLLVMDTRTQETFILKGLRKSSEYSRERKTIIPRCVPNMVCLRKYIISEE 64

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 228 SIFLHLEHVQGGTLWSHLLSQAHsrhsglssgstqermkaqlnphlnlltparlpsghapgqdrialepprtspnlllag 307
Cdd:cd05576    65 SVFLVLQHAEGGKLWSYLSKFLN--------------------------------------------------------- 87

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 308 eapstrpqreaegeptartstsgssdlpkapgghlhlqarragqnsdagpprgltwvpegagpvlggcgrGMDQSCLSAD 387
Cdd:cd05576    88 ----------------------------------------------------------------------DKEIHQLFAD 97

                         250       260       270       280       290
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1034588291 388 GAGRGCGRATWSVREEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQA 439
Cdd:cd05576    98 LDERLAAASRFYIPEECIQRWAAEMVVALDALHREGIVCRDLNPNNILLNDR 149

Catalytic domain of the Serine/Threonine Kinase, RPK118, and similar proteins; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. RPK118 contains an N-terminal Phox homology (PX) domain, a Microtubule Interacting and Trafficking (MIT) domain, and a kinase domain containing a long uncharacterized insert. Also included in the family is human RPK60 (or ribosomal protein S6 kinase-like 1), which also contains MIT and kinase domains but lacks a PX domain. RPK118 binds sphingosine kinase, a key enzyme in the synthesis of sphingosine 1-phosphate (SPP), a lipid messenger involved in many cellular events. RPK118 may be involved in transmitting SPP-mediated signaling. RPK118 also binds the antioxidant peroxiredoxin-3. RPK118 may be involved in the transport of PRDX3 from the cytoplasm to its site of function in the mitochondria. The RPK118-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 148 EQLRGCRVVGVIEKrdlavlprlvsnslpqVQLVQDPATGGTFVVKSLPRCHMVSRERLTIIPHGVPYMTKLLRYFVSED 227
Cdd:cd05576     1 EELKAFRVLGVIDK----------------VLLVMDTRTQETFILKGLRKSSEYSRERKTIIPRCVPNMVCLRKYIISEE 64

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 228 SIFLHLEHVQGGTLWSHLLSQAHsrhsglssgstqermkaqlnphlnlltparlpsghapgqdrialepprtspnlllag 307
Cdd:cd05576    65 SVFLVLQHAEGGKLWSYLSKFLN--------------------------------------------------------- 87

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 308 eapstrpqreaegeptartstsgssdlpkapgghlhlqarragqnsdagpprgltwvpegagpvlggcgrGMDQSCLSAD 387
Cdd:cd05576    88 ----------------------------------------------------------------------DKEIHQLFAD 97

                         250       260       270       280       290
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1034588291 388 GAGRGCGRATWSVREEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQA 439
Cdd:cd05576    98 LDERLAAASRFYIPEECIQRWAAEMVVALDALHREGIVCRDLNPNNILLNDR 149

Microtubule Interacting and Trafficking molecule domain;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1034588291   46 KRDYLVDAATQIRLALERDVSEDYEAAFNHYQNGVDVLLRGIHVDPNKERREAVKLKITKYLRRAEEIFNCHLQR 120
Cdd:smart00745   1 TRDYLSKAKELISKALKADEAGNYEEALELYKKAIEYLLEGIKVESDSKRREALKAKAAEYLDRAEEIKKSLLER 75

Serine/Threonine protein kinases, catalytic domain; Phosphotransferases. Serine or threonine-specific kinase subfamily.

                           10        20        30
                   ....*....|....*....|....*....|....*..
gi 1034588291  402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:smart00220  96 EDEARFYLRQILSALEYLHSKGIVHRDLKPENILLDE 132

protein kinase A catalytic subunit; Provisional

                          10        20        30
                  ....*....|....*....|....*....|...
gi 1034588291 406 KQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:PTZ00263  121 KFYHAELVLAFEYLHSKDIIYRDLKPENLLLDN 153

Catalytic domain of the Serine/Threonine Kinase, RPK118, and similar proteins; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. RPK118 contains an N-terminal Phox homology (PX) domain, a Microtubule Interacting and Trafficking (MIT) domain, and a kinase domain containing a long uncharacterized insert. Also included in the family is human RPK60 (or ribosomal protein S6 kinase-like 1), which also contains MIT and kinase domains but lacks a PX domain. RPK118 binds sphingosine kinase, a key enzyme in the synthesis of sphingosine 1-phosphate (SPP), a lipid messenger involved in many cellular events. RPK118 may be involved in transmitting SPP-mediated signaling. RPK118 also binds the antioxidant peroxiredoxin-3. RPK118 may be involved in the transport of PRDX3 from the cytoplasm to its site of function in the mitochondria. The RPK118-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 148 EQLRGCRVVGVIEKrdlavlprlvsnslpqVQLVQDPATGGTFVVKSLPRCHMVSRERLTIIPHGVPYMTKLLRYFVSED 227
Cdd:cd05576     1 EELKAFRVLGVIDK----------------VLLVMDTRTQETFILKGLRKSSEYSRERKTIIPRCVPNMVCLRKYIISEE 64

                          90       100       110       120       130       140       150       160
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 228 SIFLHLEHVQGGTLWSHLLSQAHsrhsglssgstqermkaqlnphlnlltparlpsghapgqdrialepprtspnlllag 307
Cdd:cd05576    65 SVFLVLQHAEGGKLWSYLSKFLN--------------------------------------------------------- 87

                         170       180       190       200       210       220       230       240
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 308 eapstrpqreaegeptartstsgssdlpkapgghlhlqarragqnsdagpprgltwvpegagpvlggcgrGMDQSCLSAD 387
Cdd:cd05576    88 ----------------------------------------------------------------------DKEIHQLFAD 97

                         250       260       270       280       290
                  ....*....|....*....|....*....|....*....|....*....|..
gi 1034588291 388 GAGRGCGRATWSVREEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQA 439
Cdd:cd05576    98 LDERLAAASRFYIPEECIQRWAAEMVVALDALHREGIVCRDLNPNNILLNDR 149

Microtubule Interacting and Trafficking molecule domain;

                           10        20        30        40        50        60        70
                   ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*
gi 1034588291   46 KRDYLVDAATQIRLALERDVSEDYEAAFNHYQNGVDVLLRGIHVDPNKERREAVKLKITKYLRRAEEIFNCHLQR 120
Cdd:smart00745   1 TRDYLSKAKELISKALKADEAGNYEEALELYKKAIEYLLEGIKVESDSKRREALKAKAAEYLDRAEEIKKSLLER 75

Catalytic domain of AGC family Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. AGC kinases regulate many cellular processes including division, growth, survival, metabolism, motility, and differentiation. Many are implicated in the development of various human diseases. Members of this family include cAMP-dependent Protein Kinase (PKA), cGMP-dependent Protein Kinase (PKG), Protein Kinase C (PKC), Protein Kinase B (PKB), G protein-coupled Receptor Kinase (GRK), Serum- and Glucocorticoid-induced Kinase (SGK), and 70 kDa ribosomal Protein S6 Kinase (p70S6K or S6K), among others. AGC kinases share an activation mechanism based on the phosphorylation of up to three sites: the activation loop (A-loop), the hydrophobic motif (HM) and the turn motif. Phosphorylation at the A-loop is required of most AGC kinases, which results in a disorder-to-order transition of the A-loop. The ordered conformation results in the access of substrates and ATP to the active site. A subset of AGC kinases with C-terminal extensions containing the HM also requires phosphorylation at this site. Phosphorylation at the HM allows the C-terminal extension to form an ordered structure that packs into the hydrophobic pocket of the catalytic domain, which then reconfigures the kinase into an active bi-lobed state. In addition, growth factor-activated AGC kinases such as PKB, p70S6K, RSK, MSK, PKC, and SGK, require phosphorylation at the turn motif (also called tail or zipper site), located N-terminal to the HM at the C-terminal extension. The AGC family is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and Phosphoinositide 3-Kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd05123    92 EERARFYAAEIVLALEYLHSLGIIYRDLKPENILLDS 128

MIT: domain contained within Microtubule Interacting and Trafficking molecules. This sub-family of MIT domains is found in intracellular protein transport proteins of the AAA-ATPase family. The molecular function of the MIT domain is unclear.

                          10        20        30        40        50        60
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*.
gi 1034588291  48 DYLVDAATQIRLALERDVSEDYEAAFNHYQNGVDVLLRGIHVDPNKERREAVKLKITKYLRRAEEI 113
Cdd:cd02678     1 DFLQKAIELVKKAIEEDNAGNYEEALRLYQHALEYFMHALKYEKNPKSKESIRAKCTEYLDRAEKL 66

Catalytic domain of the Serine/Threonine Kinase, Yank1; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily contains uncharacterized STKs with similarity to the human protein designated as Yank1 or STK32A. The Yank1 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05578    99 EETVKFYICEIVLALDYLHSKNIIHRDIKPDNILLD 134

MIT: domain contained within Microtubule Interacting and Trafficking molecules. This sub-family of MIT domains is found in proteins with an n-terminal serine/threonine kinase domain. The molecular function of the MIT domain is unclear.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|....*..
gi 1034588291  60 ALERDVSEDYEAAFNHYQNGVDVLLRGIHVDPNKERREAVKLKITKYLRRAEEIFNC 116
Cdd:cd02684    13 AVKKDQRGDAAAALSLYCSALQYFVPALHYETDAQRKEALRQKVLQYVSRAEELKAL 69

Catalytic domain of Protein Kinases; PKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine or tyrosine residues on protein substrates. PKs make up a large family of serine/threonine kinases (STKs), protein tyrosine kinases (PTKs), and dual-specificity PKs that phosphorylate both serine/threonine and tyrosine residues of target proteins. Majority of protein phosphorylation occurs on serine residues while only 1% occurs on tyrosine residues. Protein phosphorylation is a mechanism by which a wide variety of cellular proteins, such as enzymes and membrane channels, are reversibly regulated in response to certain stimuli. PKs often function as components of signal transduction pathways in which one kinase activates a second kinase, which in turn, may act on other kinases; this sequential action transmits a signal from the cell surface to target proteins, which results in cellular responses. The PK family is one of the largest known protein families with more than 100 homologous yeast enzymes and more than 500 human proteins. A fraction of PK family members are pseudokinases that lack crucial residues for catalytic activity. The mutiplicity of kinases allows for specific regulation according to substrate, tissue distribution, and cellular localization. PKs regulate many cellular processes including proliferation, division, differentiation, motility, survival, metabolism, cell-cycle progression, cytoskeletal rearrangement, immunity, and neuronal functions. Many kinases are implicated in the development of various human diseases including different types of cancer. The PK family is part of a larger superfamily that includes the catalytic domains of RIO kinases, aminoglycoside phosphotransferase, choline kinase, phosphoinositide 3-kinase (PI3K), and actin-fragmin kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd00180    91 EEEALSILRQLLSALEYLHSNGIIHRDLKPENILLD 126

Catalytic domain of Rho-associated coiled-coil containing protein kinase (ROCK)- and Nuclear Dbf2-Related (NDR)-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Members of this subfamily include ROCK and ROCK-like proteins such as DMPK, MRCK, and CRIK, as well as NDR and NDR-like proteins such as LATS, CBK1 and Sid2p. ROCK and CRIK are effectors of the small GTPase Rho, while MRCK is an effector of the small GTPase Cdc42. NDR and NDR-like kinases contain an N-terminal regulatory (NTR) domain and an insert within the catalytic domain that contains an auto-inhibitory sequence. Proteins in this subfamily are involved in regulating many cellular functions including contraction, motility, division, proliferation, apoptosis, morphogenesis, and cytokinesis. The ROCK/NDR-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*...
gi 1034588291 400 VREEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05573    98 FPEETARFYIAELVLALDSLHKLGFIHRDIKPDNILLD 135

Catalytic domain of the Serine/Threonine Kinase, beta-adrenergic receptor kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The beta-ARK group is composed of GRK2, GRK3, and similar proteins. GRK2 and GRK3 are both widely expressed in many tissues, although GRK2 is present at higher levels. They contain an N-terminal RGS homology (RH) domain, a central catalytic domain, and C-terminal pleckstrin homology (PH) domain that mediates PIP2 and G protein betagamma-subunit translocation to the membrane. GRK2 (also called beta-ARK or beta-ARK1) is important in regulating several cardiac receptor responses. It plays a role in cardiac development and in hypertension. Deletion of GRK2 in mice results in embryonic lethality, caused by hypoplasia of the ventricular myocardium. GRK2 also plays important roles in the liver (as a regulator of portal blood pressure), in immune cells, and in the nervous system. Altered GRK2 expression has been reported in several disorders including major depression, schizophrenia, bipolar disorder, and Parkinsonism. GRKs phosphorylate and regulate G protein-coupled receptors (GPCRs), the largest superfamily of cell surface receptors which regulate some part of nearly all physiological functions. Phosphorylated GPCRs bind to arrestins, which prevents further G protein signaling despite the presence of activating ligand. The beta-ARK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*...
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQA 439
Cdd:cd05606    97 EAEMRFYAAEVILGLEHMHNRFIVYRDLKPANILLDEH 134

Catalytic domain of the Serine/Threonine kinases, Liver Kinase B1, Calmodulin Dependent Protein Kinase Kinase, and similar proteins; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Both LKB1 and CaMKKs can phosphorylate and activate AMP-activated protein kinase (AMPK). LKB1, also called STK11, serves as a master upstream kinase that activates AMPK and most AMPK-like kinases. LKB1 and AMPK are part of an energy-sensing pathway that links cell energy to metabolism and cell growth. They play critical roles in the establishment and maintenance of cell polarity, cell proliferation, cytoskeletal organization, as well as T-cell metabolism, including T-cell development, homeostasis, and effector function. CaMKKs are upstream kinases of the CaM kinase cascade that phosphorylate and activate CaMKI and CamKIV. They may also phosphorylate other substrates including PKB and AMPK. Vertebrates contain two CaMKKs, CaMKK1 (or alpha) and CaMKK2 (or beta). CaMKK1 is involved in the regulation of glucose uptake in skeletal muscles. CaMKK2 is involved in regulating energy balance, glucose metabolism, adiposity, hematopoiesis, inflammation, and cancer. The LKB1/CaMKK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd14008   107 EETARKYFRDLVLGLEYLHENGIVHRDIKPENLLLTA 143

Catalytic domain of the Serine/Threonine Kinase, 70 kDa ribosomal protein S6 kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. p70S6K (or S6K) contains only one catalytic kinase domain, unlike p90 ribosomal S6 kinases (RSKs). It acts as a downstream effector of the STK mTOR (mammalian Target of Rapamycin) and plays a role in the regulation of the translation machinery during protein synthesis. p70S6K also plays a pivotal role in regulating cell size and glucose homeostasis. Its targets include S6, the translation initiation factor eIF3, and the insulin receptor substrate IRS-1, among others. Mammals contain two isoforms of p70S6K, named S6K1 and S6K2 (or S6K-beta). The p70S6K subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05584    99 EDTACFYLAEITLALGHLHSLGIIYRDLKPENILLD 134

Catalytic domain of the Serine/Threonine Kinase, Phosphoinositide-dependent kinase 1; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. PDK1 carries an N-terminal catalytic domain and a C-terminal pleckstrin homology (PH) domain that binds phosphoinositides. It phosphorylates the activation loop of AGC kinases that are regulated by PI3K such as PKB, SGK, and PKC, among others, and is crucial for their activation. Thus, it contributes in regulating many processes including metabolism, growth, proliferation, and survival. PDK1 also has the ability to autophosphorylate and is constitutively active in mammalian cells. It is essential for normal embryo development and is important in regulating cell volume. The PDK1 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd05581   100 EKCTRFYTAEIVLALEYLHSKGIIHRDLKPENILLDE 136

Catalytic domain of the Serine/Threonine Kinase, Protein Kinase B; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. There are three PKB isoforms from different genes, PKB-alpha (or Akt1), PKB-beta (or Akt2), and PKB-gamma (or Akt3). PKB contains an N-terminal pleckstrin homology (PH) domain and a C-terminal catalytic domain. It is activated downstream of phosphoinositide 3-kinase (PI3K) and plays important roles in diverse cellular functions including cell survival, growth, proliferation, angiogenesis, motility, and migration. PKB also has a central role in a variety of human cancers, having been implicated in tumor initiation, progression, and metastasis. The PKB subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and PI3K.

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd05571    94 EDRTRFYGAEIVLALGYLHSQGIVYRDLKLENLLLDK 130

Catalytic domain of the Serine/Threonine Kinase, Cyclin-Dependent protein Kinase 7; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CDK7 plays essential roles in the cell cycle and in transcription. It associates with cyclin H and MAT1 and acts as a CDK-Activating Kinase (CAK) by phosphorylating and activating cell cycle CDKs (CDK1/2/4/6). In the brain, it activates CDK5. CDK7 is also a component of the general transcription factor TFIIH, which phosphorylates the C-terminal domain (CTD) of RNA polymerase II when it is bound with unphosphorylated DNA, as present in the pre-initiation complex. Following phosphorylation, the CTD dissociates from the DNA which allows transcription initiation. CDKs belong to a large family of STKs that are regulated by their cognate cyclins. Together, they are involved in the control of cell-cycle progression, transcription, and neuronal function. The CDK7 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....
gi 1034588291 404 QVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd07841   103 DIKSYMLMTLRGLEYLHSNWILHRDLKPNNLLIA 136

Catalytic domain of G protein-coupled Receptor Kinase 4-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Members of the GRK4-like group include GRK4, GRK5, GRK6, and similar GRKs. They contain an N-terminal RGS homology (RH) domain and a catalytic domain, but lack a G protein betagamma-subunit binding domain. They are localized to the plasma membrane through post-translational lipid modification or direct binding to PIP2. GRKs phosphorylate and regulate G protein-coupled receptors (GPCRs), the largest superfamily of cell surface receptors which regulate some part of nearly all physiological functions. Phosphorylated GPCRs bind to arrestins, which prevents further G protein signaling despite the presence of activating ligand. The GRK4-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05605   101 EERAVFYAAEITCGLEHLHSERIVYRDLKPENILLD 136

Serine/threonine protein kinase [Signal transduction mechanisms];

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDqavvRGGAPVL 448
Cdd:COG0515   106 PAEALRILAQLAEALAAAHAAGIVHRDIKPANILLT----PDGRVKL 148

Catalytic domain of the Serine/Threonine Kinase, G protein-coupled Receptor Kinase 5; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. GRK5 is widely expressed in many tissues. It associates with the membrane though an N-terminal PIP2 binding domain and also binds phospholipids via its C-terminus. GRK5 deficiency is associated with early Alzheimer's disease in humans and mouse models. GRK5 also plays a crucial role in the pathogenesis of sporadic Parkinson's disease. It participates in the regulation and desensitization of PDGFRbeta, a receptor tyrosine kinase involved in a variety of downstream cellular effects including cell growth, chemotaxis, apoptosis, and angiogenesis. GRK5 also regulates Toll-like receptor 4, which is involved in innate and adaptive immunity. GRKs phosphorylate and regulate G protein-coupled receptors (GPCRs), the largest superfamily of cell surface receptors which regulate some part of nearly all physiological functions. Phosphorylated GPCRs bind to arrestins, which prevents further G protein signaling despite the presence of activating ligand. The GRK5 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05632   103 EERALFYAAEILCGLEDLHRENTVYRDLKPENILLD 138

Catalytic domain of Nuclear Dbf2-Related kinase-like Protein Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. NDR kinases regulate mitosis, cell growth, embryonic development, and neurological processes. They are also required for proper centrosome duplication. Higher eukaryotes contain two NDR isoforms, NDR1 and NDR2. This subfamily also contains fungal NDR-like kinases. NDR kinase contains an N-terminal regulatory (NTR) domain and an insert within the catalytic domain that contains an auto-inhibitory sequence. Like many other AGC kinases, NDR kinase requires phosphorylation at two sites, the activation loop (A-loop) and the hydrophobic motif (HM), for activity. The NDR kinase subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd05599   100 EEETRFYIAETVLAIESIHKLGYIHRDIKPDNLLLDA 136

Catalytic domain of the Serine/Threonine Kinase, Protein Kinase C; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. PKCs are classified into three groups (classical, atypical, and novel) depending on their mode of activation and the structural characteristics of their regulatory domain. PKCs undergo three phosphorylations in order to take mature forms. In addition, classical PKCs depend on calcium, DAG (1,2-diacylglycerol), and in most cases, phosphatidylserine (PS) for activation. Novel PKCs are calcium-independent, but require DAG and PS for activity, while atypical PKCs only require PS. PKCs phosphorylate and modify the activities of a wide variety of cellular proteins including receptors, enzymes, cytoskeletal proteins, transcription factors, and other kinases. They play a central role in signal transduction pathways that regulate cell migration and polarity, proliferation, differentiation, and apoptosis. Also included in this subfamily are the PKC-like proteins, called PKNs. The PKC subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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                  ....*....|....*....|....*....|....*.
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05570    95 EERARFYAAEICLALQFLHERGIIYRDLKLDNVLLD 130

protein kinase A catalytic subunit; Provisional

                          10        20        30
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gi 1034588291 406 KQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:PTZ00263  121 KFYHAELVLAFEYLHSKDIIYRDLKPENLLLDN 153

Catalytic domain of the Serine/Threonine Kinase, Mitogen-Activated Protein Kinase Kinase Kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. MAPKKKs (MKKKs or MAP3Ks) are also called MAP/ERK kinase kinases (MEKKs) in some cases. They phosphorylate and activate MAPK kinases (MAPKKs or MKKs or MAP2Ks), which in turn phosphorylate and activate MAPKs during signaling cascades that are important in mediating cellular responses to extracellular signals. This subfamily is composed of the Apoptosis Signal-regulating Kinases ASK1 (or MAPKKK5) and ASK2 (or MAPKKK6), MEKK1, MEKK2, MEKK3, MEKK4, as well as plant and fungal MAPKKKs. Also included in this subfamily are the cell division control proteins Schizosaccharomyces pombe Cdc7 and Saccharomyces cerevisiae Cdc15. The MAPKKK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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                  ....*....|....*....|....*....|....*..
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd06606    98 EPVVRKYTRQILEGLEYLHSNGIVHRDIKGANILVDS 134

Catalytic domain of the Serine/Threonine Kinase, Atypical Protein Kinase C; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. aPKCs only require phosphatidylserine (PS) for activation. They contain a C2-like region, instead of a calcium-binding (C2) region found in classical PKCs, in their regulatory domain. There are two aPKC isoforms, zeta and iota. aPKCs are involved in many cellular functions including proliferation, migration, apoptosis, polarity maintenance and cytoskeletal regulation. They also play a critical role in the regulation of glucose metabolism and in the pathogenesis of type 2 diabetes. PKCs are classified into three groups (classical, atypical, and novel) depending on their mode of activation and the structural characteristics of their regulatory domain. The aPKC subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd05588    95 EEHARFYSAEISLALNFLHEKGIIYRDLKLDNVLLDS 131

Catalytic domain of Myotonic Dystrophy protein kinase (DMPK)-like Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The DMPK-like subfamily is composed of DMPK and DMPK-related cell division control protein 42 (Cdc42) binding kinase (MRCK). DMPK is expressed in skeletal and cardiac muscles, and in central nervous tissues. The functional role of DMPK is not fully understood. It may play a role in the signal transduction and homeostasis of calcium. The DMPK gene is implicated in myotonic dystrophy 1 (DM1), an inherited multisystemic disorder with symptoms that include muscle hyperexcitability, progressive muscle weakness and wasting, cataract development, testicular atrophy, and cardiac conduction defects. The genetic basis for DM1 is the mutational expansion of a CTG repeat in the 3'-UTR of DMPK. MRCK is activated via interaction with the small GTPase Cdc42. MRCK/Cdc42 signaling mediates myosin-dependent cell motility. Three isoforms of MRCK are known, named alpha, beta and gamma. MRCKgamma is expressed in heart and skeletal muscles, unlike MRCKalpha and MRCKbeta, which are expressed ubiquitously. The DMPK-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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                  ....*....|....*....|....*....|....*.
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05597   101 EEMARFYLAEMVLAIDSIHQLGYVHRDIKPDNVLLD 136

Catalytic domain of testis-specific serine/threonine kinases and similar proteins; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. TSSK proteins are almost exclusively expressed postmeiotically in the testis and play important roles in spermatogenesis and/or spermiogenesis. There are five mammalian TSSK proteins which show differences in their localization and timing of expression. TSSK1 and TSSK2 are expressed specifically in meiotic and postmeiotic spermatogenic cells, respectively. TSSK3 has been reported to be expressed in the interstitial Leydig cells of adult testis. TSSK4, also called TSSK5, is expressed in testis from haploid round spermatids to mature spermatozoa. TSSK6, also called SSTK, is expressed at the head of elongated sperm. TSSK1/TSSK2 double knock-out and TSSK6 null mice are sterile without manifesting other defects, making these kinases viable targets for male contraception. The TSSK-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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                  ....*....|....*....|....*....|....*....|
gi 1034588291 399 SVREEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd14080    98 ALSESQARIWFRQLALAVQYLHSLDIAHRDLKCENILLDS 137

Catalytic domain of the Serine/Threonine Kinase, Citron Rho-interacting kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CRIK (also called citron kinase) is an effector of the small GTPase Rho. It plays an important function during cytokinesis and affects its contractile process. CRIK-deficient mice show severe ataxia and epilepsy as a result of abnormal cytokinesis and massive apoptosis in neuronal precursors. A Down syndrome critical region protein TTC3 interacts with CRIK and inhibits CRIK-dependent neuronal differentiation and neurite extension. CRIK contains a catalytic domain, a central coiled-coil domain, and a C-terminal region containing a Rho-binding domain (RBD), a zinc finger, and a pleckstrin homology (PH) domain, in addition to other motifs. The CRIK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05601   101 ESMARFYLAELVLAIHSLHSMGYVHRDIKPENILID 136

Catalytic domain of the Serine/Threonine Kinase, cGMP-dependent protein kinase (cGK or PKG); STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Mammals have two cGK isoforms from different genes, cGKI and cGKII. cGKI exists as two splice variants, cGKI-alpha and cGKI-beta. cGK consists of an N-terminal regulatory domain containing a dimerization and an autoinhibitory pseudosubstrate region, two cGMP-binding domains, and a C-terminal catalytic domain. Binding of cGMP to both binding sites releases the inhibition of the catalytic center by the pseudosubstrate region, allowing autophosphorylation and activation of the kinase. cGKI is a soluble protein expressed in all smooth muscles, platelets, cerebellum, and kidney. It is also expressed at lower concentrations in other tissues. cGKII is a membrane-bound protein that is most abundantly expressed in the intestine. It is also present in the brain nuclei, adrenal cortex, kidney, lung, and prostate. cGKI is involved in the regulation of smooth muscle tone, smooth cell proliferation, and platelet activation. cGKII plays a role in the regulation of secretion, such as renin secretion by the kidney and aldosterone secretion by the adrenal. It also regulates bone growth and the circadian rhythm. The cGK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 178 VQLVQDPATGGTFVVKSLPRCHMVS----------RERLTIIPHgvPYMTKLLRYFVSEDSIFLHLEHVQGGTLWSHL-- 245
Cdd:cd05572     9 VELVQLKSKGRTFALKCVKKRHIVQtrqqehifseKEILEECNS--PFIVKLYRTFKDKKYLYMLMEYCLGGELWTILrd 86

                          90
                  ....*....|
gi 1034588291 246 ---LSQAHSR 252
Cdd:cd05572    87 rglFDEYTAR 96

Catalytic subunit of the Serine/Threonine Kinases, cAMP-dependent protein kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. This subfamily is composed of the cAMP-dependent protein kinases, PKA and PRKX, and similar proteins. The inactive PKA holoenzyme is a heterotetramer composed of two phosphorylated and active catalytic subunits with a dimer of regulatory (R) subunits. Activation is achieved through the binding of the important second messenger cAMP to the R subunits, which leads to the dissociation of PKA into the R dimer and two active subunits. PKA is present ubiquitously in cells and interacts with many different downstream targets. It plays a role in the regulation of diverse processes such as growth, development, memory, metabolism, gene expression, immunity, and lipolysis. PRKX is also reulated by the R subunit and is is present in many tissues including fetal and adult brain, kidney, and lung. It is implicated in granulocyte/macrophage lineage differentiation, renal cell epithelial migration, and tubular morphogenesis in the developing kidney. The PKA-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1034588291 162 RDLAVLPRLVSNSLPQVQLVQDPATGGTFVVKSLPRC---------HMVS-RERLTIIPHgvPYMTKLLRYFVSEDSIFL 231
Cdd:cd05580     1 DDFEFLKTLGTGSFGRVRLVKHKDSGKYYALKILKKAkiiklkqveHVLNeKRILSEVRH--PFIVNLLGSFQDDRNLYM 78

                          90
                  ....*....|....
gi 1034588291 232 HLEHVQGGTLWSHL 245
Cdd:cd05580    79 VMEYVPGGELFSLL 92

Catalytic domain of the Protein Serine/Threonine Kinase, Microtubule-associated serine/threonine kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. MAST kinases contain an N-terminal domain of unknown function, a central catalytic domain, and a C-terminal PDZ domain that mediates protein-protein interactions. There are four mammalian MAST kinases, named MAST1-MAST4. MAST1 is also called syntrophin-associated STK (SAST) while MAST2 is also called MAST205. MAST kinases are cytoskeletal associated kinases of unknown function that are also expressed at neuromuscular junctions and postsynaptic densities. MAST1, MAST2, and MAST3 bind and phosphorylate the tumor suppressor PTEN, and may contribute to the regulation and stabilization of PTEN. MAST2 is involved in the regulation of the Fc-gamma receptor of the innate immune response in macrophages, and may also be involved in the regulation of the Na+/H+ exchanger NHE3. The MAST kinase subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLL 436
Cdd:cd05609    99 VDMARMYFAETVLALEYLHSYGIVHRDLKPDNLLI 133

Catalytic domain of the Serine/Threonine Kinase, cGMP-dependent protein kinase (cGK or PKG); STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Mammals have two cGK isoforms from different genes, cGKI and cGKII. cGKI exists as two splice variants, cGKI-alpha and cGKI-beta. cGK consists of an N-terminal regulatory domain containing a dimerization and an autoinhibitory pseudosubstrate region, two cGMP-binding domains, and a C-terminal catalytic domain. Binding of cGMP to both binding sites releases the inhibition of the catalytic center by the pseudosubstrate region, allowing autophosphorylation and activation of the kinase. cGKI is a soluble protein expressed in all smooth muscles, platelets, cerebellum, and kidney. It is also expressed at lower concentrations in other tissues. cGKII is a membrane-bound protein that is most abundantly expressed in the intestine. It is also present in the brain nuclei, adrenal cortex, kidney, lung, and prostate. cGKI is involved in the regulation of smooth muscle tone, smooth cell proliferation, and platelet activation. cGKII plays a role in the regulation of secretion, such as renin secretion by the kidney and aldosterone secretion by the adrenal. It also regulates bone growth and the circadian rhythm. The cGK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*..
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd05572    92 EYTARFYTACVVLAFEYLHSRGIIYRDLKPENLLLDS 128

Catalytic domain of the Serine/Threonine Kinase, G protein-coupled Receptor Kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. GRKs phosphorylate and regulate G protein-coupled receptors (GPCRs), the largest superfamily of cell surface receptors, which regulate some part of nearly all physiological functions. Phosphorylated GPCRs bind to arrestins, which prevents further G protein signaling despite the presence of activating ligand. GRKs play important roles in the cardiovascular, immune, respiratory, skeletal, and nervous systems. They contain a central catalytic domain, flanked by N- and C-terminal extensions. The N-terminus contains an RGS (regulator of G protein signaling) homology (RH) domain and several motifs. The C-terminus diverges among different groups of GRKs. There are seven types of GRKs, named GRK1 to GRK7, which are subdivided into three main groups: visual (GRK1/7); beta-adrenergic receptor kinases (GRK2/3); and GRK4-like (GRK4/5/6). Expression of GRK2/3/5/6 is widespread while GRK1/4/7 show a limited tissue distribution. The substrate spectrum of the widely expressed GRKs partially overlaps. The GRK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
                  ....*....|....*....|....*....|....*.
gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05577    94 EARAIFYAAEIICGLEHLHNRFIVYRDLKPENILLD 129

Catalytic domain of the Serine/Threonine Kinase, Mitogen-Activated Protein Kinase; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. MAPKs serve as important mediators of cellular responses to extracellular signals. They control critical cellular functions including differentiation, proliferation, migration, and apoptosis. They are also implicated in the pathogenesis of many diseases including multiple types of cancer, stroke, diabetes, and chronic inflammation. Typical MAPK pathways involve a triple kinase core cascade comprising of the MAPK, which is phosphorylated and activated by a MAPK kinase (MAP2K or MKK), which itself is phosphorylated and activated by a MAPK kinase kinase (MAP3K or MKKK). Each cascade is activated either by a small GTP-binding protein or by an adaptor protein, which transmits the signal either directly to a MAP3K to start the triple kinase core cascade or indirectly through a mediator kinase, a MAP4K. There are three typical MAPK subfamilies: Extracellular signal-Regulated Kinase (ERK), c-Jun N-terminal Kinase (JNK), and p38. Some MAPKs are atypical in that they are not regulated by MAP2Ks. These include MAPK4, MAPK6, NLK, and ERK7. The MAPK subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20
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gi 1034588291 412 MLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd07834   112 ILRGLKYLHSAGVIHRDLKPSNILVNS 138

N-terminal catalytic domain of the Serine/Threonine Kinase, Mitogen and stress-activated kinase 2; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. MSK2 and MSK1 play nonredundant roles in activating histone H3 kinases, which play pivotal roles in compaction of the chromatin fiber. MSK2 is the required H3 kinase in response to stress stimuli and activation of the p38 MAPK pathway. MSK2 also plays a role in the pathogenesis of psoriasis. MSKs contain an N-terminal kinase domain (NTD) from the AGC family and a C-terminal kinase domain (CTD) from the CAMK family, similar to 90 kDa ribosomal protein S6 kinases (RSKs). MSKs are activated by two major signaling cascades, the Ras-MAPK and p38 stress kinase pathways, which trigger phosphorylation in the activation loop (A-loop) of the CTD of MSK. The active CTD phosphorylates the hydrophobic motif (HM) of NTD, which facilitates the phosphorylation of the A-loop and activates the NTD, which in turn phosphorylates downstream targets. The MSK2 subfamily is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
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gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05614   104 EDEVRFYSGEIILALEHLHKLGIVYRDIKLENILLD 139

Catalytic domain of the Serine/Threonine kinase, Cell cycle Checkpoint Kinase 2; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Checkpoint Kinase 2 (Chk2) plays an important role in cellular responses to DNA double-strand breaks and related lesions. It is phosphorylated and activated by ATM kinase, resulting in its dissociation from sites of damage to phosphorylate downstream targets such as BRCA1, p53, cell cycle transcription factor E2F1, the promyelocytic leukemia protein (PML) involved in apoptosis, and CDC25 phosphatases, among others. Mutations in Chk2 is linked to a variety of cancers including familial breast cancer, myelodysplastic syndromes, prostate cancer, lung cancer, and osteosarcomas. Chk2 contains an N-terminal SQ/TQ cluster domain (SCD), a central forkhead-associated (FHA) domain, and a C-terminal catalytic kinase domain. The Chk2 subfamily is part of a larger superfamily that includes the catalytic domains of other protein kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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gi 1034588291 401 REEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLL 436
Cdd:cd14084   109 KEAICKLYFYQMLLAVKYLHSNGIIHRDLKPENVLL 144

Catalytic domain of the Serine/Threonine Kinase, Nuclear Dbf2-Related kinase 2; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. NDR2 (also called STK38-like) plays a role in proper centrosome duplication. In addition, it is involved in regulating neuronal growth and differentiation, as well as in facilitating neurite outgrowth. NDR2 is also implicated in fear conditioning as it contributes to the coupling of neuronal morphological changes with fear-memory consolidation. NDR kinase contains an N-terminal regulatory (NTR) domain and an insert within the catalytic domain that contains an auto-inhibitory sequence. Like many other AGC kinases, NDR kinase requires phosphorylation at two sites, the activation loop (A-loop) and the hydrophobic motif (HM), for activity. The NDR2 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
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gi 1034588291 399 SVREEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05627    98 TLSEEATQFYIAETVLAIDAIHQLGFIHRDIKPDNLLLD 136

The catalytic domain of CAMK family Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. CaMKs are multifunctional calcium and calmodulin (CaM) stimulated STKs involved in cell cycle regulation. There are several types of CaMKs including CaMKI, CaMKII, and CaMKIV. CaMKI proteins are monomeric and they play pivotal roles in the nervous system, including long-term potentiation, dendritic arborization, neurite outgrowth, and the formation of spines, synapses, and axons. CaMKII is a signaling molecule that translates upstream calcium and reactive oxygen species (ROS) signals into downstream responses that play important roles in synaptic function and cardiovascular physiology. CAMKIV is implicated in regulating several transcription factors like CREB, MEF2, and retinoid orphan receptors, as well as in T-cell development and signaling. The CAMK family also consists of other related kinases including the Phosphorylase kinase Gamma subunit (PhKG), the C-terminal kinase domains of Ribosomal S6 kinase (RSK) and Mitogen and stress-activated kinase (MSK), Doublecortin-like kinase (DCKL), and the MAPK-activated protein kinases MK2, MK3, and MK5, among others. The CAMK family is part of a larger superfamily that includes the catalytic domains of other protein STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
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gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05117    98 EREAAKIMKQILSAVAYLHSQGIVHRDLKPENILLA 133

Catalytic domain of the Serine/Threonine Kinases, Polo-like kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. PLKs play important roles in cell cycle progression and in DNA damage responses. They regulate mitotic entry, mitotic exit, and cytokinesis. In general PLKs contain an N-terminal catalytic kinase domain and a C-terminal regulatory polo box domain (PBD), which is comprised by two bipartite polo-box motifs (or polo boxes) and is involved in protein interactions. PLKs derive their names from homology to polo, a kinase first identified in Drosophila. There are five mammalian PLKs (PLK1-5) from distinct genes. There is good evidence that PLK1 may function as an oncogene while PLK2-5 have tumor suppressive properties. PLK1 functions as a positive regulator of mitosis, meiosis, and cytokinesis. PLK2 functions in G1 progression, S-phase arrest, and centriole duplication. PLK3 regulates angiogenesis and responses to DNA damage. PLK4 is required for late mitotic progression, cell survival, and embryonic development. PLK5 was first identified as a pseudogene containing a stop codon within the kinase domain, however, both murine and human genes encode expressed proteins. PLK5 functions in cell cycle arrest.

                          10        20        30
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gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLDQ 438
Cdd:cd14099   100 EPEVRYFMRQILSGVKYLHSNRIIHRDLKLGNLFLDE 136

Catalytic domain of the Serine/Threonine Kinase, Nuclear Dbf2-Related kinase 1; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. NDR1 (also called STK38) plays a role in proper centrosome duplication. It is highly expressed in thymus, muscle, lung and spleen. It is not an essential protein because mice deficient of NDR1 remain viable and fertile. However, these mice develop T-cell lymphomas and appear to be hypersenstive to carcinogenic treatment. NDR1 appears to also act as a tumor suppressor. NDR kinase contains an N-terminal regulatory (NTR) domain and an insert within the catalytic domain that contains an auto-inhibitory sequence. Like many other AGC kinases, NDR kinase requires phosphorylation at two sites, the activation loop (A-loop) and the hydrophobic motif (HM), for activity. The NDR1 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
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gi 1034588291 399 SVREEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLLD 437
Cdd:cd05628    97 TLTEEETQFYIAETVLAIDSIHQLGFIHRDIKPDNLLLD 135

Catalytic domain of the Serine/Threonine Kinase, Microtubule-associated serine/threonine-like kinase (also called greatwall kinase); STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. The MASTL kinases in this group carry only a catalytic domain, which contains a long insertion relative to MAST kinases. MASTL, also called greatwall kinase (Gwl), is involved in the regulation of mitotic entry, which is controlled by the coordinated activities of protein kinases and opposing protein phosphatases (PPs). The cyclin B/CDK1 complex induces entry into M-phase while PP2A-B55 shows anti-mitotic activity. MASTL/Gwl is activated downstream of cyclin B/CDK1 and indirectly inhibits PP2A-B55 by phosphorylating the small protein alpha-endosulfine (Ensa) or the cAMP-regulated phosphoprotein 19 (Arpp19), resulting in M-phase progression. Gwl kinase may also play roles in mRNA stabilization and DNA checkpoint recovery. The human MASTL gene has also been named FLJ14813; a missense mutation in FLJ14813 is associated with autosomal dominant thrombocytopenia. The MASTL kinase subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

                          10        20        30
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gi 1034588291 402 EEQVKQWAAEMLVALEALHEQGVLCRDLHPGNLLL 436
Cdd:cd05610   103 EEMAVKYISEVALALDYLHRHGIIHRDLKPDNMLI 137

Catalytic domain of fungal Rim15-like Protein Serine/Threonine Kinases; STKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine residues on protein substrates. Members of this group include Saccharomyces cerevisiae Rim15, Schizosaccharomyces pombe cek1, and similar fungal proteins. They contain a central catalytic domain, which contains an insert relative to MAST kinases. In addition, Rim15 contains a C-terminal signal receiver (REC) domain while cek1 contains an N-terminal PAS domain. Rim15 (or Rim15p) functions as a regulator of meiosis. It acts as a downstream effector of PKA and regulates entry into stationary phase (G0). Thus, it plays a crucial role in regulating yeast proliferation, differentiation, and aging. Cek1 may facilitate progression of mitotic anaphase. The Rim15-like subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.

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                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1034588291 178 VQLVQDPATGGTFVVKSLPRCHMVSRERLT---------IIPHGVPYMTKLLRYFVSEDSIFLHLEHVQGG 239
Cdd:cd05611    12 VYLAKKRSTGDYFAIKVLKKSDMIAKNQVTnvkaeraimMIQGESPYVAKLYYSFQSKDYLYLVMEYLNGG 82