Isolated Sos1 PH domain exhibits germinal vesicle breakdown-inducing activity in Xenopus oocytes

Jaime Font De Mora, Carmen Guerrero, Daruka Mahadevan, Juan J.R. Coque, Jose M. Rojas, Luis M. Esteban, Mario Rebecchi, Eugenio Santos

Research output: Contribution to journalArticlepeer-review

7 Scopus citations


Purified, bacterially expressed PH domains of Sos1, IRS-1, βARK, and PLCδ1 were analyzed functionally by means of microinjection into full grown, stage VI Xenopus laevis oocytes. Whereas the PH domains from IRS-1, βARK, or PLCδ1 did not show any effect in the oocytes, injection of the purified Sos1 PH domain resulted in induction of significant rates of germinal vesicle breakdown and meiotic maturation. Furthermore, the Sos1 PH domain exhibited also significant synergy with insulin or coinjected normal Ras protein in induction of germinal vesicle breakdown, although it did not affect the rate of progesterone-induced maturation. These results suggest that purified, isolated PH domains retain, at least in part, their functional specificity and that Xenopus oocytes may constitute a useful biological system to analyze the functional role of the Sos1 PH domain in Ras signaling pathways.

Original languageEnglish (US)
Pages (from-to)18272-18276
Number of pages5
JournalJournal of Biological Chemistry
Issue number30
StatePublished - 1996
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology


Dive into the research topics of 'Isolated Sos1 PH domain exhibits germinal vesicle breakdown-inducing activity in Xenopus oocytes'. Together they form a unique fingerprint.

Cite this