ADP-ribosylation factor family; Pfam combines a number of different Prosite families together

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gi 1958660390  80 TNEVVHTCSTIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSNAEIV 129
Cdd:pfam00025  22 LGEIVTTIPTIGFNVETVTYKNVKFTVWDVGGQESLRPLWRNYFPNTDAV 71

ARF-like small GTPases; ARF, ADP-ribosylation factor; Ras homologues involved in vesicular transport. Activator of phospholipase D isoforms. Unlike Ras proteins they lack cysteine residues at their C-termini and therefore are unlikely to be prenylated. ARFs are N-terminally myristoylated. Contains ATP/GTP-binding motif (P-loop).

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gi 1958660390   82 EVVHTCSTIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSNAEIVLTGIGC 135
Cdd:smart00177  37 ESVTTIPTIGFNVETVTYKNISFTVWDVGGQDKIRPLWRHYYTNTQGLIFVVDS 90

ADP-ribosylation factor(Arf)/Arf-like (Arl) small GTPases; Arf (ADP-ribosylation factor)/Arl (Arf-like) small GTPases. Arf proteins are activators of phospholipase D isoforms. Unlike Ras proteins they lack cysteine residues at their C-termini and therefore are unlikely to be prenylated. Arfs are N-terminally myristoylated. Members of the Arf family are regulators of vesicle formation in intracellular traffic that interact reversibly with membranes of the secretory and endocytic compartments in a GTP-dependent manner. They depart from other small GTP-binding proteins by a unique structural device, interswitch toggle, that implements front-back communication from N-terminus to the nucleotide binding site. Arf-like (Arl) proteins are close relatives of the Arf, but only Arl1 has been shown to function in membrane traffic like the Arf proteins. Arl2 has an unrelated function in the folding of native tubulin, and Arl4 may function in the nucleus. Most other Arf family proteins are so far relatively poorly characterized. Thus, despite their significant sequence homologies, Arf family proteins may regulate unrelated functions.

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gi 1958660390  79 LTNEVVHTCSTIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSNAEIVL 130
Cdd:cd00878    20 KLGEVVTTIPTIGFNVETVEYKNVKFTVWDVGGQDKIRPLWKHYYENTDGLI 71

ADP-ribosylation factor family; Pfam combines a number of different Prosite families together

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gi 1958660390  80 TNEVVHTCSTIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSNAEIV 129
Cdd:pfam00025  22 LGEIVTTIPTIGFNVETVTYKNVKFTVWDVGGQESLRPLWRNYFPNTDAV 71

ADP-ribosylation factor-1 (Arf1) and ADP-ribosylation factor-5 (Arf5); The Arf1-Arf5-like subfamily contains Arf1, Arf2, Arf3, Arf4, Arf5, and related proteins. Arfs1-5 are soluble proteins that are crucial for assembling coat proteins during vesicle formation. Each contains an N-terminal myristoylated amphipathic helix that is folded into the protein in the GDP-bound state. GDP/GTP exchange exposes the helix, which anchors to the membrane. Following GTP hydrolysis, the helix dissociates from the membrane and folds back into the protein. A general feature of Arf1-5 signaling may be the cooperation of two Arfs at the same site. Arfs1-5 are generally considered to be interchangeable in function and location, but some specific functions have been assigned. Arf1 localizes to the early/cis-Golgi, where it is activated by GBF1 and recruits the coat protein COPI. It also localizes to the trans-Golgi network (TGN), where it is activated by BIG1/BIG2 and recruits the AP1, AP3, AP4, and GGA proteins. Humans, but not rodents and other lower eukaryotes, lack Arf2. Human Arf3 shares 96% sequence identity with Arf1 and is believed to generally function interchangeably with Arf1. Human Arf4 in the activated (GTP-bound) state has been shown to interact with the cytoplasmic domain of epidermal growth factor receptor (EGFR) and mediate the EGF-dependent activation of phospholipase D2 (PLD2), leading to activation of the activator protein 1 (AP-1) transcription factor. Arf4 has also been shown to recognize the C-terminal sorting signal of rhodopsin and regulate its incorporation into specialized post-Golgi rhodopsin transport carriers (RTCs). There is some evidence that Arf5 functions at the early-Golgi and the trans-Golgi to affect Golgi-associated alpha-adaptin homology Arf-binding proteins (GGAs).

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gi 1958660390  69 HKLHLdktpsltNEVVHTCSTIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSNAE 127
Cdd:cd04150    18 YKLKL-------GEIVTTIPTIGFNVETVEYKNISFTVWDVGGQDKIRPLWRHYFQNTQ 69

Arf-related protein 1 (Arfrp1); Arfrp1 (Arf-related protein 1), formerly known as ARP, is a membrane-associated Arf family member that lacks the N-terminal myristoylation motif. Arfrp1 is mainly associated with the trans-Golgi compartment and the trans-Golgi network, where it regulates the targeting of Arl1 and the GRIP domain-containing proteins, golgin-97 and golgin-245, onto Golgi membranes. It is also involved in the anterograde transport of the vesicular stomatitis virus G protein from the Golgi to the plasma membrane, and in the retrograde transport of TGN38 and Shiga toxin from endosomes to the trans-Golgi network. Arfrp1 also inhibits Arf/Sec7-dependent activation of phospholipase D. Deletion of Arfrp1 in mice causes embryonic lethality at the gastrulation stage and apoptosis of mesodermal cells, indicating its importance in development.

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gi 1958660390  89 TIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSNA 126
Cdd:cd04160    38 TVGLNIGTIEVGKARLMFWDLGGQEELRSLWDKYYAES 75

Arf-like 3 (Arl3) GTPase; Arl3 (Arf-like 3) is an Arf family protein that differs from most Arf family members in the N-terminal extension. In is inactive, GDP-bound form, the N-terminal extension forms an elongated loop that is hydrophobically anchored into the membrane surface; however, it has been proposed that this region might form a helix in the GTP-bound form. The delta subunit of the rod-specific cyclic GMP phosphodiesterase type 6 (PDEdelta) is an Arl3 effector. Arl3 binds microtubules in a regulated manner to alter specific aspects of cytokinesis via interactions with retinitis pigmentosa 2 (RP2). It has been proposed that RP2 functions in concert with Arl3 to link the cell membrane and the cytoskeleton in photoreceptors as part of the cell signaling or vesicular transport machinery. In mice, the absence of Arl3 is associated with abnormal epithelial cell proliferation and cyst formation.

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gi 1958660390  79 LTNEVV-HTCSTIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSNAEIVLTGIGCRPPGR 140
Cdd:cd04155    35 LASEDIsHITPTQGFNIKNVQADGFKLNVWDIGGQRKIRPYWRNYFENTDVLIYVIDSADRKR 97

Arf-like tumor suppressor gene 1 (ARLTS1 or Arl11); ARLTS1 (Arf-like tumor suppressor gene 1), also known as Arl11, is a member of the Arf family of small GTPases that is believed to play a major role in apoptotic signaling. ARLTS1 is widely expressed and functions as a tumor suppressor gene in several human cancers. ARLTS1 is a low-penetrance suppressor that accounts for a small percentage of familial melanoma or familial chronic lymphocytic leukemia (CLL). ARLTS1 inactivation seems to occur most frequently through biallelic down-regulation by hypermethylation of the promoter. In breast cancer, ARLTS1 alterations were typically a combination of a hypomorphic polymorphism plus loss of heterozygosity. In a case of thyroid adenoma, ARLTS1 alterations were polymorphism plus promoter hypermethylation. The nonsense polymorphism Trp149Stop occurs with significantly greater frequency in familial cancer cases than in sporadic cancer cases, and the Cys148Arg polymorphism is associated with an increase in high-risk familial breast cancer.

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gi 1958660390  82 EVVHTCSTIGSNVEEIVFQR-THFLMWDLGGQEALRSTWETYYSNAEIVL 130
Cdd:cd04156    23 ELVTTIPTVGFNVEMLQLEKhLSLTVWDVGGQEKMRTVWKCYLENTDGLV 72

(ADP-ribosylation factor domain protein 1 (ARD1); ARD1 (ADP-ribosylation factor domain protein 1) is an unusual member of the Arf family. In addition to the C-terminal Arf domain, ARD1 has an additional 46-kDa N-terminal domain that contains a RING finger domain, two predicted B-Boxes, and a coiled-coil protein interaction motif. This domain belongs to the TRIM (tripartite motif) or RBCC (RING, B-Box, coiled-coil) family. Like most Arfs, the ARD1 Arf domain lacks detectable GTPase activity. However, unlike most Arfs, the full-length ARD1 protein has significant GTPase activity due to the GAP (GTPase-activating protein) activity exhibited by the 46-kDa N-terminal domain. The GAP domain of ARD1 is specific for its own Arf domain and does not bind other Arfs. The rate of GDP dissociation from the ARD1 Arf domain is slowed by the adjacent 15 amino acids, which act as a GDI (GDP-dissociation inhibitor) domain. ARD1 is ubiquitously expressed in cells and localizes to the Golgi and to the lysosomal membrane. Two Tyr-based motifs in the Arf domain are responsible for Golgi localization, while the GAP domain controls lysosomal localization.

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gi 1958660390  81 NEVVHTCSTIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSNAEIVL 130
Cdd:cd04158    22 DEFMQPIPTIGFNVETVEYKNLKFTIWDVGGKHKLRPLWKHYYLNTQAVV 71

Arf-like 6 (Arl6) GTPase; Arl6 (Arf-like 6) forms a subfamily of the Arf family of small GTPases. Arl6 expression is limited to the brain and kidney in adult mice, but it is expressed in the neural plate and somites during embryogenesis, suggesting a possible role for Arl6 in early development. Arl6 is also believed to have a role in cilia or flagella function. Several proteins have been identified that bind Arl6, including Arl6 interacting protein (Arl6ip), and SEC61beta, a subunit of the heterotrimeric conducting channel SEC61p. Based on Arl6 binding to these effectors, Arl6 is also proposed to play a role in protein transport, membrane trafficking, or cell signaling during hematopoietic maturation. At least three specific homozygous Arl6 mutations in humans have been found to cause Bardet-Biedl syndrome, a disorder characterized by obesity, retinopathy, polydactyly, renal and cardiac malformations, learning disabilities, and hypogenitalism. Older literature suggests that Arl6 is a part of the Arl4/Arl7 subfamily, but analyses based on more recent sequence data place Arl6 in its own subfamily.

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gi 1958660390  75 KTPSLTNEvvHTCSTIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSN 125
Cdd:cd04157    20 KPSNAQSQ--NIVPTVGFNVESFKKGNLSFTAFDMSGQGKYRGLWEHYYKN 68

Sar1 is an essential component of COPII vesicle coats; Sar1 is an essential component of COPII vesicle coats involved in export of cargo from the ER. The GTPase activity of Sar1 functions as a molecular switch to control protein-protein and protein-lipid interactions that direct vesicle budding from the ER. Activation of the GDP to the GTP-bound form of Sar1 involves the membrane-associated guanine nucleotide exchange factor (GEF) Sec12. Sar1 is unlike all Ras superfamily GTPases that use either myristoyl or prenyl groups to direct membrane association and function, in that Sar1 lacks such modification. Instead, Sar1 contains a unique nine-amino-acid N-terminal extension. This extension contains an evolutionarily conserved cluster of bulky hydrophobic amino acids, referred to as the Sar1-N-terminal activation recruitment (STAR) motif. The STAR motif mediates the recruitment of Sar1 to ER membranes and facilitates its interaction with mammalian Sec12 GEF leading to activation.

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gi 1958660390  71 LHLDKTpsltNEVVHTCSTIGSNVEEIVFQRTHFLMWDLGGQEALRSTWETYYSNAEIVLTGIGCRPPGR 140
Cdd:cd00879    36 LHMLKD----DRLAQHVPTLHPTSEELTIGNVKFTTFDLGGHEQARRVWKDYFPEVDGIVFLVDAADPER 101

Rab GTPase family 30 (Rab30); Rab30 subfamily. Rab30 appears to be associated with the Golgi stack. It is expressed in a wide variety of tissue types and in humans maps to chromosome 11. GTPase activating proteins (GAPs) interact with GTP-bound Rab and accelerate the hydrolysis of GTP to GDP. Guanine nucleotide exchange factors (GEFs) interact with GDP-bound Rabs to promote the formation of the GTP-bound state. Rabs are further regulated by guanine nucleotide dissociation inhibitors (GDIs), which facilitate Rab recycling by masking C-terminal lipid binding and promoting cytosolic localization. Most Rab GTPases contain a lipid modification site at the C-terminus, with sequence motifs CC, CXC, or CCX. Lipid binding is essential for membrane attachment, a key feature of most Rab proteins. Due to the presence of truncated sequences in this CD, the lipid modification site is not available for annotation.

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gi 1958660390  96 EIVFQRTHFLMWDLGGQEALRSTWETYY--SNAEIVLTGIGCRPPGRsCIRSW 146
Cdd:cd04114    50 EIKGEKIKLQIWDTAGQERFRSITQSYYrsANALILTYDITCEESFR-CLPEW 101