FYVE domain like superfamily; FYVE domain is a 60-80 residue double zinc finger motif-containing module named after the four proteins, Fab1, YOTB, Vac1, and EEA1. The canonical FYVE domains are distinguished from other zinc fingers by three signature sequences: an N-terminal WxxD motif (x for any residue), the central basic R(R/K)HHCRxCG patch, and a C-terminal RVC motif, which form a compact phosphatidylinositol 3-phosphate (PtdIns3P, also termed PI3P)-binding site. They are found in many membrane trafficking regulators, including EEA1, Hrs, Vac1p, Vps27p, and FENS-1, which locate to early endosomes, specifically bind PtdIns3P, and play important roles in vesicular traffic and in signal transduction. Some proteins, such as rabphilin-3A and alpha-Rab3-interacting molecules (RIMs), are also involved in membrane trafficking and bind to members of the Rab subfamily of GTP hydrolases. However, they contain FYVE-related domains that are structurally similar to the canonical FYVE domains but lack the three signature sequences. At this point, they may not bind to phosphoinositides. In addition, this superfamily also contains the third group of proteins, caspase-associated ring proteins CARP1 and CARP2. They do not localize to membranes in the cell and are involved in the negative regulation of apoptosis, specifically targeting two initiator caspases, caspase 8 and caspase 10, which are distinguished from other FYVE-type proteins. Moreover, these proteins have an altered sequence in the basic ligand binding patch and lack the WxxD motif that is conserved only in phosphoinositide binding FYVE domains. Thus they constitute a family of unique FYVE-type domains called FYVE-like domains. The FYVE domain is structurally similar to the RING domain and the PHD finger. This superfamily also includes ADDz zinc finger domain, which is a PHD-like zinc finger motif that contains two parts, a C2-C2 and a PHD-like zinc finger.

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gi 2462611453  60 EKCCARCQQVLGFLLHRGAVCRGCSHRVCAQCRVFLRGtHAWKCTVCFE 108
Cdd:cd15765     1 ERSCARCQKPLGKLLNRGAVCNGCSHRVCSECRVFLGR-EIWKCTVCHA 48

FYVE-related domain found in synaptotagmin-like protein 3 (Slp3) and similar proteins; Slp3, also termed exophilin-6, functions as a Rab27A-specific effector in cytotoxic T lymphocytes. It binds to kinesin-1 motor through interaction with the tetratricopeptide repeat of the kinesin-1 light chain (KLC1). The kinesin-1/Slp3/Rab27a complex plays a role in mediating the terminal transport of lytic granules to the immune synapse. Slp3 contains an N-terminal Slp homology domain (SHD) and C-terminal tandem C2 domains. The Slp homology domain (SHD) consists of two conserved regions, designated SHD1 (Slp homology domain 1) and SHD2, which may function as protein interaction sites. The SHD1 and SHD2 of Slp3 are separated by a putative FYVE zinc finger, which resembles a FYVE-related domain that is structurally similar to the canonical FYVE domains but lacks the three signature sequences: an N-terminal WxxD motif (x for any residue), the central basic R(R/K)HHCRxCG patch, and a C-terminal RVC motif. In addition, the Slp3 C2A domain showed Ca2+-dependent phospholipid binding activity. At this point, Slp3 is a Ca2+-dependent isoform in Slp proteins family.

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gi 2462611453  60 EKCCARCQQVLGFLLHRGAVCRGCSHRVCAQCRVFLRGtHAWKCTVCFE 108
Cdd:cd15765     1 ERSCARCQKPLGKLLNRGAVCNGCSHRVCSECRVFLGR-EIWKCTVCHA 48

Protein present in Fab1, YOTB, Vac1, and EEA1; The FYVE zinc finger is named after four proteins where it was first found: Fab1, YOTB/ZK632.12, Vac1, and EEA1. The FYVE finger has been shown to bind two Zn2+ ions. The FYVE finger has eight potential zinc coordinating cysteine positions. The FYVE finger is structurally related to the PHD finger and the RING finger. Many members of this family also include two histidines in a motif R+HHC+XCG, where + represents a charged residue and X any residue. The FYVE finger functions in the membrane recruitment of cytosolic proteins by binding to phosphatidylinositol 3-phosphate (PI3P), which is prominent on endosomes. The R+HHC+XCG motif is critical for PI3P binding.

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gi 2462611453   53 NTDWE--HKEKCCARCQQVLGFLLhRGAVCRGCSHRVCAQC---RVFLRGTHAWK----CTVCFEDRN 111
Cdd:smart00064   1 RPHWIpdEEVSNCMGCGKEFNLTK-RRHHCRNCGRIFCSKCsskKAPLPKLGIERpvrvCDDCYENLN 67

FYVE-related domain found in synaptotagmin-like protein 3 (Slp3) and similar proteins; Slp3, also termed exophilin-6, functions as a Rab27A-specific effector in cytotoxic T lymphocytes. It binds to kinesin-1 motor through interaction with the tetratricopeptide repeat of the kinesin-1 light chain (KLC1). The kinesin-1/Slp3/Rab27a complex plays a role in mediating the terminal transport of lytic granules to the immune synapse. Slp3 contains an N-terminal Slp homology domain (SHD) and C-terminal tandem C2 domains. The Slp homology domain (SHD) consists of two conserved regions, designated SHD1 (Slp homology domain 1) and SHD2, which may function as protein interaction sites. The SHD1 and SHD2 of Slp3 are separated by a putative FYVE zinc finger, which resembles a FYVE-related domain that is structurally similar to the canonical FYVE domains but lacks the three signature sequences: an N-terminal WxxD motif (x for any residue), the central basic R(R/K)HHCRxCG patch, and a C-terminal RVC motif. In addition, the Slp3 C2A domain showed Ca2+-dependent phospholipid binding activity. At this point, Slp3 is a Ca2+-dependent isoform in Slp proteins family.

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gi 2462611453  60 EKCCARCQQVLGFLLHRGAVCRGCSHRVCAQCRVFLRGtHAWKCTVCFE 108
Cdd:cd15765     1 ERSCARCQKPLGKLLNRGAVCNGCSHRVCSECRVFLGR-EIWKCTVCHA 48

FYVE-related domain found in the synaptotagmin-like proteins 3, 4, 5; The synaptotagmin-like proteins 1-5 (Slp1-5) family belongs to the carboxyl-terminal-type (C-type) tandem C2 proteins superfamily, which also contains the synaptotagmin and the Doc2 families. Slp proteins are putative membrane trafficking proteins that are characterized by the presence of a unique N-terminal Slp homology domain (SHD), and C-terminal tandem C2 domains (known as the C2A domain and C2B domain). The SHD consists of two conserved regions, designated SHD1 (Slp homology domain 1) and SHD2. The SHD1 and SHD2 of Slp3, Slp4 and Slp5 are separated by a putative FYVE zinc finger. By contrast, Slp1 and Slp2 lack such zinc finger and their SHD1 and SHD2 are linked together. This model corresponds to the FYVE zinc finger. At this point, Slp1 and Slp2 are not included in this model. Moreover, the FYVE domains of Slp3, Slp4 and Slp5 resemble a FYVE-related domain that is structurally similar to the canonical FYVE domains but lacks the three signature sequences: an N-terminal WxxD motif (x for any residue), the central basic R(R/K)HHCRxCG patch, and a C-terminal RVC motif.

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gi 2462611453  61 KCCARCQQVLGFLLHRGAVCRGCSHRVCAQCRVFLRGTHAWKCTVCFE 108
Cdd:cd15747     1 RICARCREKLGFIFNRGARCPKCSHKVCKKCRVLTSNTGKWLCTVCHK 48

FYVE-related domain found in Slp homolog lacking C2 domains a (SlaC2-a) and similar proteins; SlaC2-a, also termed melanophilin, or exophilin-3, is a GTP-bound form of Rab27A-, myosin Va-, and actin-binding protein present on melanosomes. It is involved in the control of transferring of melanosomes from microtubules to actin filaments. It also functions as a melanocyte type myosin Va (McM5) binding partner and directly activates the actin-activated ATPase activity of McM5 through forming a tripartite protein complex with Rab27A and an actin-based motor myosin Va. SlaC2-a belongs to the Slp homolog lacking C2 domains (Slac2) family. It contains an N-terminal Slp homology domain (SHD), but lacks tandem C2 domains. The SHD consists of two conserved regions, designated SHD1 (Slp homology domain 1) and SHD2, which may function as protein interaction sites. The SHD1 and SHD2 of SlaC2-a are separated by a putative FYVE zinc finger, which resembles a FYVE-related domain that is structurally similar to the canonical FYVE domains but lacks the three signature sequences: an N-terminal WxxD motif (x for any residue), the central basic R(R/K)HHCRxCG patch, and a C-terminal RVC motif. Moreover, Slac2-a has a middle myosin-binding domain and a C-terminal actin-binding domain.

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gi 2462611453  63 CARCQQVLGFLLHRGAVCRGCSHRVCAQCRVFLRGTHAWKCTVCFEDRNVKIKTGEWFYEERAKKF 128
Cdd:cd15752     3 CARCLQPFQFLLNSGRQCLDCGLRTCKSCSRYHPEEQGWVCDPCHLARVVKIGSLEWYYNHVRARF 68

FYVE-related domain found in Slp homolog lacking C2 domains c (SlaC2-c) and similar proteins; SlaC2-c, also termed Rab effector MyRIP, or exophilin-8, or myosin-VIIa- and Rab-interacting protein, or synaptotagmin-like protein lacking C2 domains c, is a GTP-bound form of Rab27A-, myosin Va/VIIa-, and actin-binding protein mainly present on retinal melanosomes and secretory granules. It may play a role in insulin granule exocytosis. It is also involved in the control of isoproterenol (IPR)-induced amylase release from parotid acinar cells. SlaC2-c belongs to the Slp homolog lacking C2 domains (Slac2) family. It contains an N-terminal Slp homology domain (SHD), but lacks tandem C2 domains. The SHD consists of two conserved regions, designated SHD1 (Slp homology domain 1) and SHD2, which may function as protein interaction sites. The SHD1 and SHD2 of SlaC2-c are separated by a putative FYVE zinc finger, which resembles a FYVE-related domain that is structurally similar to the canonical FYVE domains but lacks the three signature sequences: an N-terminal WxxD motif (x for any residue), the central basic R(R/K)HHCRxCG patch, and a C-terminal RVC motif. Moreover, Slac2-c has a middle myosin-binding domain and a C-terminal actin-binding domain.

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gi 2462611453  62 CCARCQQVLGFLLHRGAVCRGCSHRVCAQCRVFLRGTHAWKCTVCFEDR 110
Cdd:cd15753     1 CCMRCCSPFTFLFNRKRQCRDCKFNVCKSCASYDKKEKGWTCNVCQKQR 49

FYVE-related domain found in Rab effector Noc2 and similar proteins; Rab effector Noc2, also termed No C2 domains protein, or rabphilin-3A-like protein (RPH3AL), is a Rab3 effector that mediates the regulation of secretory vesicle exocytosis in neurons and certain endocrine cells. It also functions as a Rab27 effector and is involved in isoproterenol (IPR)-stimulated amylase release from acinar cells. Noc2 contains an N-terminal Rab3A effector domain which harbors a conserved zinc finger, but lacks tandem C2 domains. The FYVE domain of Noc2 resembles a FYVE-related domain that is structurally similar to the canonical FYVE domains but lacks the three signature sequences: an N-terminal WxxD motif (x for any residue), the central basic R(R/K)HHCRxCG patch, and a C-terminal RVC motif.

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gi 2462611453  63 CARCQQVLGFLLHRGAVCRGCSHRVCAQCRVFLRGTHA---WKCTVCFEDRNV 112
Cdd:cd15763    10 CLLCGELLGFLGSSSVFCQDCRKKVCTKCGIETSGSQKrplWLCKICSEQREV 62