Details

Autor(en) / Beteiligte

• Hu, Qianjin
• Klippel, Anke
• Muslin, Anthony J.
• Fantl, Wendy J.
• Williams, Lewis T.

Titel

Ras-Dependent Induction of Cellular Responses by Constitutively Active Phosphatidylinositol-3 Kinase

Ist Teil von

• Science (American Association for the Advancement of Science), 1995-04, Vol.268 (5207), p.100-102

Ort / Verlag

Washington, DC: American Society for the Advancement of Science

Erscheinungsjahr

1995

Quelle

MEDLINE

Beschreibungen/Notizen

• Phosphatidylinositol (PI)-3 kinase is one of many enzymes stimulated by growth factors. A constitutively activated mutant, p110*, that functions independently of growth factor stimulation was constructed to determine the specific responses regulated by PI-3 kinase. The p110* protein exhibited high specific activity as a PI-3 kinase and as a protein kinase. Expression of p110* in NIH 3T3 cells induced transcription from the fos promoter. Co-expression of dominant negative Ras blocked this response. When expressed in Xenopus laevis oocytes, p110* increased the amount of guanosine 5′-triphosphate-bound Ras, caused activation of the Ras effector Raf-1, and induced Ras-dependent oocyte maturation. These findings show that PI-3 kinase can stimulate diverse Ras-dependent cellular processes, including oocyte maturation and fos transcription.