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New responsibilities for the PI3K regulatory subunit p85 alpha

K Okkenhaug1, B Vanhaesebroeck

  • 1Ludwig Institute for Cancer Research, University College London Branch, 91 Riding House Street, London W1W 8BT, UK. klaus@ludwig.ucl.ac.uk,

Science'S STKE : Signal Transduction Knowledge Environment
|December 26, 2001
PubMed

Class IA phosphoinositide-3 kinases (PI3Ks) are heterodimeric enzymes that regulate many signal transduction pathways. The p85 regulatory subunit recruits the p110 catalytic subunit to the membrane, where p110 phosphorylates inositol lipids. Recent studies present evidence for an additional role for p85alpha in the regulation of actin cytoskeleton. Okkenhaug and Vanhaesebroeck discuss these results and ask whether experiments describing p85alpha knockout mice need to be reinterpreted.

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