P-loop containing Nucleoside Triphosphate Hydrolases; Members of the P-loop NTPase domain superfamily are characterized by a conserved nucleotide phosphate-binding motif, also referred to as the Walker A motif (GxxxxGK[S/T], where x is any residue), and the Walker B motif (hhhh[D/E], where h is a hydrophobic residue). The Walker A and B motifs bind the beta-gamma phosphate moiety of the bound nucleotide (typically ATP or GTP) and the Mg2+ cation, respectively. The P-loop NTPases are involved in diverse cellular functions, and they can be divided into two major structural classes: the KG (kinase-GTPase) class which includes Ras-like GTPases and its circularly permutated YlqF-like; and the ASCE (additional strand catalytic E) class which includes ATPase Binding Cassette (ABC), DExD/H-like helicases, 4Fe-4S iron sulfur cluster binding proteins of NifH family, RecA-like F1-ATPases, and ATPases Associated with a wide variety of Activities (AAA). Also included are a diverse set of nucleotide/nucleoside kinase families.

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gi 968121903  67 AAPRAGVEDAFYTLVREIR 85
Cdd:cd04138  144 AKTRQGVEEAFYTLVREIR 162

Ras GTPase family containing H-Ras,N-Ras and K-Ras4A/4B; H-Ras/N-Ras/K-Ras subfamily. H-Ras, N-Ras, and K-Ras4A/4B are the prototypical members of the Ras family. These isoforms generate distinct signal outputs despite interacting with a common set of activators and effectors, and are strongly associated with oncogenic progression in tumor initiation. Mutated versions of Ras that are insensitive to GAP stimulation (and are therefore constitutively active) are found in a significant fraction of human cancers. Many Ras guanine nucleotide exchange factors (GEFs) have been identified. They are sequestered in the cytosol until activation by growth factors triggers recruitment to the plasma membrane or Golgi, where the GEF colocalizes with Ras. Active (GTP-bound) Ras interacts with several effector proteins that stimulate a variety of diverse cytoplasmic signaling activities. Some are known to positively mediate the oncogenic properties of Ras, including Raf, phosphatidylinositol 3-kinase (PI3K), RalGEFs, and Tiam1. Others are proposed to play negative regulatory roles in oncogenesis, including RASSF and NORE/MST1. Most Ras proteins contain a lipid modification site at the C-terminus, with a typical sequence motif CaaX, where a = an aliphatic amino acid and X = any amino acid. Lipid binding is essential for membrane attachment, a key feature of most Ras 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 968121903  67 AAPRAGVEDAFYTLVREIR 85
Cdd:cd04138  144 AKTRQGVEEAFYTLVREIR 162

Ras GTPase family containing H-Ras,N-Ras and K-Ras4A/4B; H-Ras/N-Ras/K-Ras subfamily. H-Ras, N-Ras, and K-Ras4A/4B are the prototypical members of the Ras family. These isoforms generate distinct signal outputs despite interacting with a common set of activators and effectors, and are strongly associated with oncogenic progression in tumor initiation. Mutated versions of Ras that are insensitive to GAP stimulation (and are therefore constitutively active) are found in a significant fraction of human cancers. Many Ras guanine nucleotide exchange factors (GEFs) have been identified. They are sequestered in the cytosol until activation by growth factors triggers recruitment to the plasma membrane or Golgi, where the GEF colocalizes with Ras. Active (GTP-bound) Ras interacts with several effector proteins that stimulate a variety of diverse cytoplasmic signaling activities. Some are known to positively mediate the oncogenic properties of Ras, including Raf, phosphatidylinositol 3-kinase (PI3K), RalGEFs, and Tiam1. Others are proposed to play negative regulatory roles in oncogenesis, including RASSF and NORE/MST1. Most Ras proteins contain a lipid modification site at the C-terminus, with a typical sequence motif CaaX, where a = an aliphatic amino acid and X = any amino acid. Lipid binding is essential for membrane attachment, a key feature of most Ras proteins. Due to the presence of truncated sequences in this CD, the lipid modification site is not available for annotation.

                         10
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gi 968121903  67 AAPRAGVEDAFYTLVREIR 85
Cdd:cd04138  144 AKTRQGVEEAFYTLVREIR 162

Ral (Ras-like) family containing highly homologous RalA and RalB; The Ral (Ras-like) subfamily consists of the highly homologous RalA and RalB. Ral proteins are believed to play a crucial role in tumorigenesis, metastasis, endocytosis, and actin cytoskeleton dynamics. Despite their high sequence similarity (>80% sequence identity), nonoverlapping and opposing functions have been assigned to RalA and RalBs in tumor migration. In human bladder and prostate cancer cells, RalB promotes migration while RalA inhibits it. A Ral-specific set of GEFs has been identified that are activated by Ras binding. This RalGEF activity is enhanced by Ras binding to another of its target proteins, phosphatidylinositol 3-kinase (PI3K). Ral effectors include RLIP76/RalBP1, a Rac/cdc42 GAP, and the exocyst (Sec6/8) complex, a heterooctomeric protein complex that is involved in tethering vesicles to specific sites on the plasma membrane prior to exocytosis. In rat kidney cells, RalB is required for functional assembly of the exocyst and for localizing the exocyst to the leading edge of migrating cells. In human cancer cells, RalA is required to support anchorage-independent proliferation and RalB is required to suppress apoptosis. RalA has been shown to localize to the plasma membrane while RalB is localized to the intracellular vesicles. Most Ras proteins contain a lipid modification site at the C-terminus, with a typical sequence motif CaaX, where a = an aliphatic amino acid and X = any amino acid. Lipid binding is essential for membrane attachment, a key feature of most Ras 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 968121903  67 AAPRAGVEDAFYTLVREIRQ 86
Cdd:cd04139  144 AKTRANVDKVFFDLVREIRQ 163