The domain within your query sequence starts at position 174 and ends at position 282; the E-value for the PI3K_rbd domain shown below is 1.88e-42.



PI3-kinase family, Ras-binding domain
SMART accession number:SM00144
Description: Certain members of the PI3K family possess Ras-binding domains in their N-termini. These regions show some similarity (although not highly significant similarity) to Ras-binding RA domains (unpublished observation).
Interpro abstract (IPR000341):

Phosphatidylinositol 3-kinases (PI3Ks) are lipid kinases that phosphorylate 4,5-bisphonate (PI(4,5) P2 or PIP2) at the 3-position of the inositol ring, and thus generate phosphatidylinositol 3,4,5-trisphosphate (PIP3), which, in turns, initiates a vast array of signaling events. PI3Ks can be grouped into three classes based on their domain organisation. Class I PI3Ks are heterodimers consisting of a p110 catalytic subunit and a regulatory subunit of either the p85 type (associated with the class IA p110 isoforms p110alpha, p110beta or p110delta) or the p101 type (associated with the class IB p110 isoform p110gamma). Common to all catalytic subunits are an N-terminal adaptor-binding domain (ABD) that binds to p85, a Ras- binding domain (RBD), a putative membrane-binding domain (C2), a helical domain of unknown function, and a kinase catalytic domain. Class II PI3Ks lack the ABD domain and are distinguished by a carboxy terminal C2 domain. Class III enzymes lack the ABD and RBD domains [ (PUBMED:17626883) (PUBMED:18079394) (PUBMED:20081827) (PUBMED:10580505) ].

PI3K RBD is a small globular domain of about 100 residues in length with an alpha/beta-sandwich topology. The PI3K RBD domain consists of a five-stranded mixed beta-sheet flanked by two alpha-helices [ (PUBMED:17626883) (PUBMED:18079394) (PUBMED:20081827) (PUBMED:10580505) ].

Family alignment:
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There are 3332 PI3K_rbd domains in 3329 proteins in SMART's nrdb database.

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