PIK3R1 (phosphoinositide-3-kinase, regulatory subunit 1 (alpha))

p84, a New Gβγ-Activated Regulatory Subunit of the Type IB Phosphoinositide 3-Kinase p110γ

A variety of genetic and inhibitor studies have shown that phosphoinositide 3-kinase (PI3K ) plays an essential role in a number of physiological responses, including neutrophil chemotaxis, mast cell degranulation, and cardiac function [1–6]. PI3K is currently thought to be composed of a p110 catalytic subunit and a single regulatory subunit, p101. The binding of p110 to p101 dramatically incre...

The p85 Regulatory Subunit of Class IA Phosphoinositide 3-Kinase Regulates -Selection in Thymocyte Development

ErbB3 (HER3) interaction with the p85 regulatory subunit of phosphoinositide 3-kinase.

ErbB3 (HER3), a unique member of the ErbB receptor family, lacks intrinsic protein tyrosine kinase activity and contains six Tyr-Xaa-Xaa-Met (YXXM) consensus binding sites for the SH2 domains of the p85 regulatory subunit of phosphoinositide 3-kinase. ErbB3 also has a proline-rich sequence that forms a consensus binding site for the SH3 domain of p85. Here we have investigated the interacting d...

The tyrosine phosphatase CD148 interacts with the p85 regulatory subunit of phosphoinositide 3-kinase.

CD148 is a transmembrane tyrosine phosphatase that has been implicated in the regulation of cell growth and transformation. However, the signalling mechanisms of CD148 are incompletely understood. To identify the specific intracellular molecules involved in CD148 signalling, we carried out a modified yeast two-hybrid screening assay. Using the substrate-trapping mutant form of CD148 (CD148 D/A)...

Identification and characterization of a new oncogene derived from the regulatory subunit of phosphoinositide 3-kinase.

p85/p110 phosphoinositide 3-kinase (PI3K) is a heterodimer composed of a p85-regulatory and a p110-catalytic subunit, which is involved in a variety of cellular responses including cytoskeletal organization, cell survival and proliferation. We describe here the cloning and characterization of p65-PI3K, a mutant of the regulatory subunit of PI3K, which includes the initial 571 residues of the wi...