basic Helix Loop Helix (bHLH) domain superfamily; bHLH proteins are transcriptional regulators that are found in organisms from yeast to humans. Members of the bHLH superfamily have two highly conserved and functionally distinct regions. The basic part is at the amino end of the bHLH that may bind DNA to a consensus hexanucleotide sequence known as the E box (CANNTG). Different families of bHLH proteins recognize different E-box consensus sequences. At the carboxyl-terminal end of the region is the HLH region that interacts with other proteins to form homo- and heterodimers. bHLH proteins function as a diverse set of regulatory factors because they recognize different DNA sequences and dimerize with different proteins. The bHLH proteins can be divided to cell-type specific and widely expressed proteins. The cell-type specific members of bHLH superfamily are involved in cell-fate determination and act in neurogenesis, cardiogenesis, myogenesis, and hematopoiesis.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 75677394  78 SPENAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTLG 133
Cdd:cd19709   1 SPENAARERSRVRTLRQAFLALQAALPSVPPDTKLSKLDVLVLATSYIAHLTRTLD 56

basic helix-loop-helix (bHLH) domain found in transcription factor 23 (TCF-23) and similar proteins; TCF-23, also termed Class A basic helix-loop-helix protein 24 (bHLHa24), is a bHLH transcription factor that is essential for progesterone-dependent decidualization. The mouse homolog is also called ovary, uterus and testis protein (OUT), which is expressed predominantly in the reproductive organs such as the uterus, ovary and testis. It shows an Id-like inhibitory activity and functions as a negative regulator of bHLH factors through the formation of a functionally inactive heterodimeric complex. OUT inhibits the formation of TCF3 and MYOD1 homodimers and heterodimers, but lacks DNA binding activity. OUT is involved in the regulation or modulation of smooth muscle contraction of the uterus during pregnancy and particularly around the time of delivery. It also plays a role in the inhibition of myogenesis. Unlike typical bHLH factors, OUT proteins do not bind E-box (CANNTG) or N-box DNA sequences and inhibit DNA binding of homo- and heterodimers consisting of E12 and MyoD in gel mobility shift assays.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 75677394  78 SPENAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTLG 133
Cdd:cd19709   1 SPENAARERSRVRTLRQAFLALQAALPSVPPDTKLSKLDVLVLATSYIAHLTRTLD 56

Helix-loop-helix DNA-binding domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 75677394    83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLT 129
Cdd:pfam00010   7 ERERRRRDRINDAFDELRELLPTLPPDKKLSKAEILRLAIEYIKHLQ 53

basic helix-loop-helix (bHLH) domain found in transcription factor 23 (TCF-23) and similar proteins; TCF-23, also termed Class A basic helix-loop-helix protein 24 (bHLHa24), is a bHLH transcription factor that is essential for progesterone-dependent decidualization. The mouse homolog is also called ovary, uterus and testis protein (OUT), which is expressed predominantly in the reproductive organs such as the uterus, ovary and testis. It shows an Id-like inhibitory activity and functions as a negative regulator of bHLH factors through the formation of a functionally inactive heterodimeric complex. OUT inhibits the formation of TCF3 and MYOD1 homodimers and heterodimers, but lacks DNA binding activity. OUT is involved in the regulation or modulation of smooth muscle contraction of the uterus during pregnancy and particularly around the time of delivery. It also plays a role in the inhibition of myogenesis. Unlike typical bHLH factors, OUT proteins do not bind E-box (CANNTG) or N-box DNA sequences and inhibit DNA binding of homo- and heterodimers consisting of E12 and MyoD in gel mobility shift assays.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 75677394  78 SPENAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTLG 133
Cdd:cd19709   1 SPENAARERSRVRTLRQAFLALQAALPSVPPDTKLSKLDVLVLATSYIAHLTRTLD 56

basic helix-loop-helix (bHLH) domain found in transcription factor 24 (TCF-24) and similar proteins; TCF-24 is an uncharacterized bHLH transcription factor that shows high sequence similarity with TCF-23.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*.
gi 75677394  77 ASPENAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19710   1 PAAANAARERSRVQTLRSAFLELQRTLPSVPPDTKLSKLDVLVLATTYIAHLMRTL 56

basic helix-loop-helix (bHLH) domain found in musculin, transcription factor 21 (TCF-21) and similar proteins; The family includes two bHLH transcription factors, musculin and transcription factor 21 (TCF-21). Musculin, also termed activated B-cell factor 1 (ABF-1), or Class A basic helix-loop-helix protein 22 (bHLHa22), is a bHLH transcription factor expressed in activated B lymphocytes. It acts as a transcription repressor capable of inhibiting the transactivation capability of TCF3/E47. Musculin may play a role in regulating antigen-dependent B-cell differentiation. The mouse homolog, musculin, is suggested to be a repressor of myogenesis that is expressed in developing muscle and in the spleen. TCF-21, also termed capsulin, or Class A basic helix-loop-helix protein 23 (bHLHa23), or epicardin, or podocyte-expressed 1 (Pod-1), is a bHLH transcription factor expressed specifically in mesodermally-derived cells that surround the epithelium of the developing gastrointestinal, genitourinary and respiratory systems during mouse embryogenesis. It may play a role in the specification or differentiation of one or more subsets of epicardial cell types.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd11423   7 ARERARMRVLSKAFSRLKTTLPWVPPDTKLSKLDTLRLAASYIAHLRQIL 56

basic helix-loop-helix (bHLH) domain found in musculin and similar proteins; Musculin, also termed activated B-cell factor 1 (ABF-1), or Class A basic helix-loop-helix protein 22 (bHLHa22), is a bHLH transcription factor expressed in activated B lymphocytes. It acts as a transcription repressor capable of inhibiting the transactivation capability of TCF3/E47. Musculin may play a role in regulating antigen-dependent B-cell differentiation. The mouse homolog, musculin, is suggested to be a repressor of myogenesis that is expressed in developing muscle and in the spleen. Musculin heterodimerizes with products of the E2A gene.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19703  10 ARERARMRVLSKAFSRLKTSLPWVPPDTKLSKLDTLRLASSYIAHLRQLL 59

Helix-loop-helix DNA-binding domain;

                          10        20        30        40
                  ....*....|....*....|....*....|....*....|....*..
gi 75677394    83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLT 129
Cdd:pfam00010   7 ERERRRRDRINDAFDELRELLPTLPPDKKLSKAEILRLAIEYIKHLQ 53

basic helix-loop-helix (bHLH) domain found in protein atonal homolog 8 (ATOH8) and similar proteins; ATOH8, also termed Class A basic helix-loop-helix protein 21 (bHLHa21), or helix-loop-helix protein hATH-6 (hATH6), is a bHLH shear-stress-responsive transcription factor expressed in activated satellite cells and proliferating myoblasts of human skeletal muscle tissue. It regulates endothelial cell proliferation, migration and tube-like structures formation. ATOH8 binds a palindromic (canonical) core consensus DNA sequence 5'-CANNTG- 3' known as an E-box element, possibly as a heterodimer with other bHLH proteins.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....*
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTLGHELP 137
Cdd:cd11421  14 ARERTRVHTISAAFEALRKAVPSYSYNQKLSKLAILRIACSYILALARLADLDYS 68

basic helix-loop-helix (bHLH) domain found in muscle, intestine and stomach expression 1 (MIST-1) and similar proteins; MIST-1, also termed Class A basic helix-loop-helix protein 15 (bHLHa15), or Class B basic helix-loop-helix protein 8 (bHLHb8), is a bHLH transcription factor expressed in pancreatic acinar cells and other serous exocrine cells. It is essential for cytoskeletal organization and secretory activity. It also functions as a potent endoplasmic reticulum (ER) stress-inducible transcriptional regulator. MIST-1 is capable of binding to E-box (CANNTG) motifs as a homodimer or a heterodimer with E-proteins (E12 and E47) to regulate transcription.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 75677394  80 ENAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19711   4 ESNERERQRMHKLNNAFQALREVIPHVRAEKKLSKIETLTLAKNYIKSLTTTI 56

basic helix-loop-helix (bHLH) domain found in helix-loop-helix protein (HEN) family; The HEN family includes two neuron-specific bHLH transcription factors, HEN-1 (also known as Nhlh1 or bHLHa35 or NSCL-1) and HEN-2 (also known as Nhlh2 or bHLHa34 or NSCL-2). They may serve as DNA-binding protein that is involved in the control of cell-type determination, possibly within the developing nervous system.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 75677394  81 NAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd11414   6 HATRERIRVEAFNSAFAQLRKLLPTLPPDKKLSKIEILRLAICYISYLNHVL 57

basic helix-loop-helix (bHLH) domain found in achaete-scute complex-like (ASCL) family; The achaete-scute complex-like (ASCL, also known as achaete-scute complex homolog or ASH) family of bHLH transcription factors, ASCL1-5, have been implicated in cell fate specification and differentiation. They are critical for proper development of the nervous system. The deregulation of ASCL plays a key role in psychiatric and neurological disorders. ASCL-1, also termed Class A basic helix-loop-helix protein 46 (bHLHa46), or achaete-scute homolog 1 (ASH-1), or mammalian achaete-scute homolog 1 (Mash1), is a neural-specific bHLH transcription factor that is expressed in subsets of neural progenitors in both the central and peripheral nervous system. It plays a key role in neuronal differentiation and specification in the nervous system. ASCL-2, also termed achaete-scute homolog 2 (ASH-2), or Class A basic helix-loop-helix protein 45 (bHLHa45), or mammalian achaete-scute homolog 2 (Mash2), is a bHLH transcription factor that is involved in Schwann cell differentiation and control of proliferation in adult peripheral nerves. ASCL-3, also termed Class A basic helix-loop-helix protein 42 (bHLHa42), or bHLH transcriptional regulator Sgn-1, or achaete-scute homolog 3 (ASH-3), is a bHLH transcription factor specifically localized in the duct cells of the salivary glands. It may act as transcriptional repressor that inhibits myogenesis. The family also includes Drosophila melanogaster achaete-scute complex (AS-C) proteins, which consists of lethal of scute (also known as achaete-scute complex protein T3 or AST3), scute (also known as achaete-scute complex protein T4 or AST4), achaete (also known as achaete-scute complex protein T5 or AST5), and asense (also known as achaete-scute complex protein T8 or AST8). They are involved in the determination of the neuronal precursors in the peripheral nervous system and the central nervous system, as well as in sex determination and dosage compensation.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd11418   7 ERERRRVQAVNDAFDRLRQHVPYLKRRKKLSKVKTLRRAIEYIRHLQKLL 56

basic helix-loop-helix (bHLH) domain found in heart- and neural crest derivatives-expressed protein 2 (HAND2) and similar proteins; HAND2, also termed Class A basic helix-loop-helix protein 26 (bHLHa26), or deciduum, heart, autonomic nervous system and neural crest derivatives-expressed protein 2 (dHAND), is a bHLH transcription factor that is essential for cardiac morphogenesis, particularly for the formation of the right ventricle and of the aortic arch arteries.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|....
gi 75677394  84 RERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTLGHELP 137
Cdd:cd11471   8 KERRRTQSINSAFAELRECIPNVPADTKLSKIKTLRLATSYIAYLMDLLAKDDQ 61

basic helix-loop-helix (bHLH) domain found in helix-loop-helix protein 1 (HEN-1) and similar proteins; HEN-1, also termed nescient helix-loop-helix 1 (Nhlh1), or Class A basic helix-loop-helix protein 35 (bHLHa35), or nescient helix loop helix 1 (NSCL-1), is a neuron-specific bHLH transcription factor that may serve as DNA-binding protein and may be involved in the control of cell-type determination, possibly within the developing nervous system.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 75677394  81 NAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19701  20 HATRERIRVEAFNVAFAELRKLLPTLPPDKKLSKIEILRLAICYISYLNHVL 71

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster protein taxi and similar proteins; Protein taxi, also termed protein delilah (Dei), is a bHLH transcription factor that is involved in regulation of cell adhesion and attachment that is expressed in specialized cells that provide anchoring sites to either muscles (tendon cells), or proprioceptors (chordotonal attachment cells) during embryonic development. It probably plays an important role in the differentiation of epidermal cells into the tendon cells that form the attachment sites for all muscles.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAVPP---DTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd11431   7 ARERDRMREINDAFEALRRAVPEYPVagkDGKLTKITTLRLAMNYIKALTDLL 59

basic helix-loop-helix (bHLH) domain found in scleraxis and similar proteins; Scleraxis, also termed SCX, or Class A basic helix-loop-helix protein 41 (bHLHa41), or Class A basic helix-loop-helix protein 48 (bHLHa48), is a bHLH transcription factor that is expressed in sclerotome limb bud cranial and body wall mesenchyme, pericardium and heart valves, ligaments and tendons. It is required for tendon formation ligaments, connective tissue, the diaphragm, and testis development. Scleraxis plays a central role in promoting fibroblast proliferation and matrix synthesis during the embryonic development of tendons.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd18951  10 ARERDRTNSVNTAFTALRTLIPTEPADRKLSKIETLRLASSYISHLGNVL 59

basic helix-loop-helix (bHLH) domain found in helix-loop-helix protein 2 (HEN-2) and similar proteins; HEN-2, also termed nescient helix-loop-helix 2 (Nhlh2), or Class A basic helix-loop-helix protein 34 (bHLHa34), or nescient helix loop helix 2 (NSCL-2), is a neuron-specific bHLH transcription factor that may serve as DNA-binding protein and may be involved in the control of cell-type determination, possibly within the developing nervous system.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|..
gi 75677394  81 NAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19702  20 HATRERIRVEAFNLAFAELRKLLPTLPPDKKLSKIEILRLAICYISYLNHVL 71

basic helix-loop-helix (bHLH) domain found in twist-related protein 1 (TWIST1) and similar proteins; TWIST1, also termed Class A basic helix-loop-helix protein 38 (bHLHa38), or H-twist, is a bHLH transcriptional regulator that inhibits myogenesis by sequestrating E proteins, inhibiting trans-activation by MEF2, and inhibiting DNA-binding by MYOD1 through physical interaction. It also represses expression of proinflammatory cytokines such as TNFA and IL1B. In addition, TWIST1 is involved in cancer development and progression.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 75677394  84 RERSRVRTLRQAFLALQAALPAVPPDtKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd11412  19 RERQRTQSLNEAFAALRKIIPTLPSD-KLSKIQTLKLAARYIDFLYQVL 66

basic helix-loop-helix (bHLH) domain found in Drosophila melanogaster protein dimmed and similar proteins; Dimmed, also termed DIMM, is a bHLH transcription factor that regulates neurosecretory (NS) cell function and neuroendocrine cell fate in Drosophila.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 75677394  80 ENAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLT 129
Cdd:cd19712   4 ESNERERMRMHSLNDAFQGLREVIPHVNAERKLSKIETLTLAKNYIKALT 53

basic helix-loop-helix (bHLH) domain found in twist-related protein (TWIST) family; The TWIST family includes TWIST1 and TWIST2, which are highly homologous bHLH transcription factors that promote epithelial-mesenchymal transition (EMT) during development and tumor metastasis. They are involved in the negative regulation of cellular determination and in the differentiation of several lineages, including myogenesis, osteogenesis, and neurogenesis. TWIST factors express in broad partially-overlapping patterns during embryo development and dimerize with a broad sets of dimer partners that form numerous unique transcriptional complexes to regulate embryonic development.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 75677394  84 RERSRVRTLRQAFLALQAALPAVPPDtKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd11464   8 RERQRTQSLNEAFTSLRKIIPTLPSD-KLSKIQTLKLAARYIDFLYQVL 55

basic helix-loop-helix (bHLH) domain found in neurogenin-1 (NGN-1) and similar proteins; NGN-1, also termed Class A basic helix-loop-helix protein 6 (bHLHa6), or neurogenic basic-helix-loop-helix protein, or neurogenic differentiation factor 3 (NeuroD3), is a neural-specific bHLH transcription factor involved in the initiation of neuronal differentiation. It activates transcription by binding to the E box (5'-CANNTG-3').

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 75677394  84 RERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19716  24 RERNRMHNLNAALDELRSVLPSFPDDTKLTKIETLRFAHNYIWALSETL 72

basic helix-loop-helix (bHLH) domain found in pancreas transcription factor 1 subunit alpha (PTF1A) and similar proteins; PTF1A, also termed Class A basic helix-loop-helix protein 29 (bHLHa29), or pancreas-specific transcription factor 1a, or bHLH transcription factor p48, or p48 DNA-binding subunit of transcription factor PTF1 (PTF1-p48), is a bHLH transcription factor implicated in the cell fate determination in various organs. It binds to the E-box consensus sequence 5'-CANNTG-3' and plays a role in early and late pancreas development and differentiation.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 75677394  84 RERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd11417   8 RERRRMQSINDAFEGLRSHIPTLPYEKRLSKVDTLRLAIGYINFLSELV 56

basic helix-loop-helix (bHLH) domain found in protein atonal homolog 1 (ATOH1) and similar proteins; ATOH1, also termed Class A basic helix-loop-helix protein 14 (bHLHa14), or helix-loop-helix protein hATH-1 (hATH1), or Math1, or Cath1, is a proneural bHLH transcription factor that is essential for inner ear hair cell differentiation. It dimerizes with E47 and activates E-box (CANNTG) dependent transcription. ATOH1 is a mammalian homolog of the Drosophila melanogaster gene atonal and mouse atonal homolog 1 (Math1).

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19713  12 ARERRRMHGLNHAFDQLRNVIPSFNNDKKLSKYETLQMAQIYINALSELL 61

basic helix-loop-helix (bHLH) domain found in protein atonal homolog 7 (ATOH7) and similar proteins; ATOH7, also termed Class A basic helix-loop-helix protein 13 (bHLHa13), or helix-loop-helix protein hATH-5 (hATH5), or Math5, is a bHLH transcription factor involved in the differentiation of retinal ganglion cells.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19714  14 ARERRRMQGLNTAFDRLRKVVPQWGQDKKLSKYETLQMALSYIMALTRIL 63

basic helix-loop-helix (bHLH) domain found in twist-related protein 2 (TWIST2) and similar proteins; TWIST2, also termed Class A basic helix-loop-helix protein 39 (bHLHa39), or Dermis-expressed protein 1, or Dermo-1, is a bHLH transcription factor that regulates the development of mesenchymal tissues and plays a critical role in embryogenesis. It binds to the E-box consensus sequence 5'-CANNTG-3' as a heterodimer and inhibits transcriptional activation by MYOD1, MYOG, MEF2A and MEF2C.

                        10        20        30        40
                ....*....|....*....|....*....|....*....|....*....
gi 75677394  84 RERSRVRTLRQAFLALQAALPAVPPDtKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19700  24 RERQRTQSLNEAFAALRKIIPTLPSD-KLSKIQTLKLAARYIDFLYQVL 71

basic helix-loop-helix (bHLH) domain found in neurogenic differentiation factor (NeuroD) family; The NeuroD family includes NeuroD1, NeuroD2, NeuroD4 and NeuroD6. NeuroD1, also termed Class A basic helix-loop-helix protein 3 (bHLHa3), is a neuronal bHLH transcription factor involved in the development and maintenance of the endocrine pancreas and neuronal elements. It acts as an essential regulator of glutamatergic neuronal differentiation. Loss of NeuroD1 causes ataxia, cerebellar hypoplasia, sensorineural deafness, and severe retinal dystrophy in mice. NeuroD2, also termed Class A basic helix-loop-helix protein 1 (bHLHa1), or NeuroD-related factor (NDRF), is a neuronal calcium-dependent bHLH transcription factor that induces neuronal differentiation and promotes neuronal survival. It plays a central role in thalamocortical synaptic maturation. NeuroD2 mediates calcium-dependent transcription activation by binding to E box-containing promoter. NeuroD4, also termed Class A basic helix-loop-helix protein 4 (bHLHa4), or protein atonal homolog 3 (ATH-3), or Atoh3, or Math-3, is a bHLH transcriptional activator that mediates neuronal differentiation. NeuroD6, also termed Class A basic helix-loop-helix protein 2 (bHLHa2), or protein atonal homolog 2 (ATH-2), or Atoh2, or Math2, or Nex1, is a neurogenic bHLH transcription factor involved in neuronal development, differentiation, and survival in Alzheimer's disease (AD) brains of both cohorts. It plays an integrative role in coordinating increase in mitochondrial mass with cytoskeletal remodeling, suggesting that it may act as a co-regulator of neuronal differentiation and energy metabolism.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd11427   6 ARERNRMHGLNDALDNLRKVVPCYSKTQKLSKIETLRLARNYIWALSEIL 55

basic helix-loop-helix (bHLH) domain found in achaete-scute-like protein 4 (ASCL-4) and similar proteins; ASCL-4, also termed Class A basic helix-loop-helix protein 44 (bHLHa44), or achaete-scute homolog 4 (ASH-4), or Hash4, is a bHLH transcriptional regulator that may be involved in skin development.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|
gi 75677394  84 RERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTLG 133
Cdd:cd19746  15 RERQRVRCVNEGYARLREHLPQELADKRLSKVETLRAAIDYIKHLQELLE 64

basic helix-loop-helix (bHLH) domain found in neurogenic differentiation factor 6 (NeuroD6) and similar proteins; NeuroD6, also termed Class A basic helix-loop-helix protein 2 (bHLHa2), or protein atonal homolog 2 (ATH-2), or Atoh2, or Math2, or Nex1, is a neurogenic bHLH transcription factor involved in neuronal development, differentiation, and survival in Alzheimer's disease (AD) brains of both cohorts. It plays an integrative role in coordinating increase in mitochondrial mass with cytoskeletal remodeling, suggesting that it may act as a co-regulator of neuronal differentiation and energy metabolism.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 75677394  80 ENAARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19722  17 EANARERNRMHGLNDALDSLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 69

basic helix-loop-helix (bHLH) domain found in mesoderm posterior protein (Mesp) family; Mesp, a bHLH tissue specific transcription factor, acts as a key regulator of the cardiovascular transcriptional network by inducing directly and/or indirectly the expression of the majority of key cardiovascular transcription factors. The Mesp family includes two bHLH transcription factors, Mesp1 and Mesp2. Mesp1, also termed Class C basic helix-loop-helix protein 5 (bHLHc5), promotes cardiovascular differentiation during embryonic development and embryonic stem cell differentiation. Mesp2, also termed Class C basic helix-loop-helix protein 6 (bHLHc6), plays an important role in somitogenesis. The family also includes mesogenin-1 (Msgn1) and similar proteins. Msgn1, also termed paraxial mesoderm-specific mesogenin1, or pMesogenin1 (pMsgn1), is a bHLH transcription factor required for maturation and segmentation of paraxial mesoderm. It may regulate the expression of T-box transcription factors essential for mesoderm formation and differentiation.

                        10        20        30        40        50
                ....*....|....*....|....*....|....*....|....*....|...
gi 75677394  83 ARERSRVRTLRQAFLALQAALPAV--PPDTKLSKLDVLVLAASYIAHLTRTLG 133
Cdd:cd11425   7 ERERLRMRTLADALGELRQHLPPSvaPKGKRLSKIQTLKYAIRYIGYLGNVLQ 59

basic helix-loop-helix (bHLH) domain found in Oligodendrocyte lineage genes (OLIG) family of transcription factors; The OLIG family includes three bHLH transcription factors, Oligo1-3, which are expressed in both the developing and mature central nervous system. Oligo1 and Oligo2 are expressed in a nervous tissue-specific manner, but Oligo3 is found mainly in non-neural tissues. Oligo (also known as Olig) have key roles in the specification of motor neurons, dorsal interneurons, and oligodendrocytes. Oligo1, also termed Class B basic helix-loop-helix protein 6 (bHLHb6), or Class E basic helix-loop-helix protein 21 (bHLHe21), promotes formation and maturation of oligodendrocytes, especially within the brain. Oligo2, also termed Class B basic helix-loop-helix protein 1 (bHLHb1), or Class E basic helix-loop-helix protein 19 (bHLHe19), or protein kinase C-binding protein 2, or protein kinase C-binding protein RACK17, is required for oligodendrocyte and motor neuron specification in the spinal cord, as well as for the development of somatic motor neurons in the hindbrain. It cooperates with OLIG1 to establish the MN progenitors (pMN) domain of the embryonic neural tube. Oligo3, also termed Class B basic helix-loop-helix protein 7 (bHLHb7), or Class E basic helix-loop-helix protein 20 (bHLHe20), is expressed in the ventricular zone of the dorsal alar plate of the hindbrain and involved in regulating the development of dorsal and ventral spinal cord. It may determine the distinct specification program of class A neurons in the dorsal part of the spinal cord and suppress specification of class B neurons. This family also includes two OLIG-related bHLH transcription factors, bHLHe22 and bHLHe23. bHLHe22, also termed Class B basic helix-loop-helix protein 5 (bHLHb5), or trinucleotide repeat-containing gene 20 protein, is a neural-specific transcriptional repressor that is expressed in both excitatory (unipolar brush cells) and inhibitory neurons (cartwheel cells) of the dorsal cochlear nucleus (DCN) during development. It is important for the proper development and/or survival of a number of neural cell types. bHLHe23, also termed Class B basic helix-loop-helix protein 4 (bHLHb4), is expressed in rod bipolar cells and is required for rod bipolar cell maturation. bHLHe23 have roles in spinal interneuron differentiation by mechanisms linked to the Notch signaling pathway. It modulates the expression of genes required for the differentiation and/or maintenance of pancreatic and neuronal cell types.

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gi 75677394  83 ARERSRVRTLRQAFLALQAALP--AVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd11429   6 SRERKRMHDLNSALDGLRSVMPyaQGPSVRKLSKIATLLLARNYILMLTQAL 57

basic Helix-Loop-Helix-zipper (bHLHzip) domain found in MAX gene-associated protein (MGA) family; The MGA family includes MGA, Schizosaccharomyces pombe ESC1 (spESC1) and similar proteins. MGA, also termed MAX dimerization protein 5 (MAD5), is a dual specificity T-box/ bHLHzip transcription factor that regulates the expression of both Max-network and T-box family target genes. It contains a Myc-like bHLHZip motif and requires heterodimerization with Max for binding to the preferred Myc-Max-binding site CACGTG. In addition to the bHLHZip domain, MGA harbors a second DNA-binding domain, the T-box or T-domain. It thus binds the preferred Brachyury-binding sequence and represses transcription of reporter genes containing promoter-proximal Brachyury-binding sites. spESC1 is a bHLHzip protein with homology to human MyoD and Myf-5 myogenic differentiation inducers. It is involved in the sexual differentiation process.

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gi 75677394  84 RERSRVRTLRQAFLALQAALPAvPPDTKLSKLDVLVLAASYIAHLTR 130
Cdd:cd19682   7 RERERRSELRELFDKLKQLLGL-DSDEKASKLAVLTEAIEEIQQLKR 52

basic helix-loop-helix (bHLH) domain found in neurogenic differentiation factor 2 (NeuroD2) and similar proteins; NeuroD2, also termed Class A basic helix-loop-helix protein 1 (bHLHa1), or NeuroD-related factor (NDRF), is a neuronal calcium-dependent bHLH transcription factor that induces neuronal differentiation and promotes neuronal survival. It plays a central role in thalamocortical synaptic maturation. NeuroD2 mediates calcium-dependent transcription activation by binding to E box-containing promoter.

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gi 75677394  61 GPRGTRAGGLALGRSEASPENA-ARERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19720  18 GPKKRKMTKARLERSKLRRQKAnARERNRMHDLNSALDNLRKVVPCYSKTQKLSKIETLRLAKNYIWALSEIL 90

basic helix-loop-helix (bHLH) domain found in achaete-scute-like protein 5 (ASCL-5) and similar proteins; ASCL-5, also termed Class A basic helix-loop-helix protein 47 (bHLHa47), or achaete-scute homolog 5 (ASH-5), is an uncharacterized bHLH transcription factor that belongs to AS-C (achaete, scute, lethal of scute, and asense) family.

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gi 75677394  84 RERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19747  13 RERQRVKCVNEGYARLRDHLPGAMAEKRLSKVETLRAAIRYIKYLQDLL 61

basic helix-loop-helix (bHLH) domain found in achaete-scute-like protein 3 (ASCL-3) and similar proteins; ASCL-3, also termed Class A basic helix-loop-helix protein 42 (bHLHa42), or bHLH transcriptional regulator Sgn-1, or achaete-scute homolog 3 (ASH-3), is a bHLH transcription factor specifically localized in the duct cells of the salivary glands. It may act as transcriptional repressor that inhibits myogenesis.

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                ....*....|....*....|....*....|....*....|....*....
gi 75677394  84 RERSRVRTLRQAFLALQAALPAVPPDTKLSKLDVLVLAASYIAHLTRTL 132
Cdd:cd19745  11 RERQRVKCVNEGYAKLRRHLPQEYSEKRLSKVETLRAAIKYIKHLQSVL 59

basic helix-loop-helix (bHLH) domain found in Arabidopsis thaliana genes coding transcription factors and similar proteins; bHLH proteins are the second largest class of plant transcription factors that regulate transcription of genes that are involve in many essential physiological and developmental process. bHLH proteins are transcriptional regulators that are found in organisms from yeast to humans. The Arabidopsis bHLH proteins that have been characterized so far have roles in regulation of fruit dehiscence, cell development (carpel, anther and epidermal), phytochrome signaling, flavonoid biosynthesis, hormone signaling and stress responses.

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gi 75677394  84 RERSRVRTLRQAFLALQAAlpaVPPDTKLSKLDVLVLAASYIAHL 128
Cdd:cd11393   4 AERKRREKINERIRALRSL---VPNGGKTDKASILDEAIEYIKFL 45