Phosphatidylinositol 3-kinase: Structure and expression of the 110 Kd catalytic subunit
- Hiles, I.D. 3
- Otsu, M. 3
- Volinia, S. 3
- Fry, M.J. 3
- Gout, I. 3
- Dhand, R. 3
- Panayotou, G. 3
- Ruiz-Larrea, F. 1
- Thompson, A. 3
- Totty, N.F. 3
- Hsuan, J.J. 3
- Courtneidge, S.A. 2
- Parker, P.J. 2
- Waterfield, M.D. 3
-
1
University College London
info
- 2 Differentiation Programme European Molecular Biology Laboratory, 6900 Heidelberg, Germany
- 3 Ludwig Institute for Cancer Research, London, W1P 8BT England, United Kingdom
ISSN: 0092-8674
Datum der Publikation: 1992
Ausgabe: 70
Nummer: 3
Seiten: 419-429
Art: Artikel
Andere Publikationen in: Cell (Cambridge)
Zusammenfassung
Purified bovine brain phosphatidylinositol 3-kinase (P13-kinase) is composed of 85 kd and 110 kd subunits. The 85 kd subunit (p85α) lacks P13- kinase activity and acts as an adaptor, coupling the 110 kd subunit (p110) to activated protein tyrosine kinases. Here the characterization of the p110 subunit is presented. cDNA cloning reveals p110 to be a 1068 aa protein related to Vps34p, a S. cerevisiae protein involved in the sorting of proteins to the vacuole. p110 expressed in insect cells possesses P13-kinase activity and associates with p85α into an active p85α-p110 complex that binds the activated colony-stimulating factor 1 receptor. p110 expressed in COS-1 cells is catalytically active only when complexed with p85α.