[HTML][HTML] Tyrosine phosphorylation of p85 relieves its inhibitory activity on phosphatidylinositol 3-kinase
BD Cuevas, Y Lu, M Mao, J Zhang, R LaPushin… - Journal of Biological …, 2001 - ASBMB
Under resting conditions, the p85 regulatory subunit of phosphatidylinositol 3-kinase (PI3K)
serves to both stabilize and inactivate the p110 catalytic subunit. The inhibitory activity of
p85 is relieved by occupancy of the NH 2-terminal SH2 domain of p85 by phosphorylated
tyrosine. Src family kinases phosphorylate tyrosine 688 in p85, a process that we have
shown to be reversed by the activity of the p85-associated SH2 domain-containing
phosphatase SHP1. We demonstrate that phosphorylation of the downstream PI3K target …
serves to both stabilize and inactivate the p110 catalytic subunit. The inhibitory activity of
p85 is relieved by occupancy of the NH 2-terminal SH2 domain of p85 by phosphorylated
tyrosine. Src family kinases phosphorylate tyrosine 688 in p85, a process that we have
shown to be reversed by the activity of the p85-associated SH2 domain-containing
phosphatase SHP1. We demonstrate that phosphorylation of the downstream PI3K target …