The phosphatidylinositol 3-kinase/Akt signaling pathway modulates the endocrine differentiation of trophoblast cells

Takayuki Kamei, Stephanie R. Jones, Belinda M. Chapman, Kerry L Kreidel, Guoli Dai, Michael J. Soares

Research output: Contribution to journalArticle

40 Scopus citations


Activation of Lyn, a Src-related nonreceptor tyrosine kinase, in trophoblast cells is associated with trophoblast giant cell differentiation. The purpose of the present work was to use Lyn as a tool to identify signaling pathways regulating the endocrine differentiation of trophoblast cells. The Src homology 3 domain of Lyn was shown to display differentiation-dependent associations with other regulatory proteins, including phosphatidylinositol 3-kinase (PI3-K). PI3-K activation was dependent upon trophoblast giant cell differentiation. The downstream mediator of PI3-K, Akt/protein kinase B, also exhibited differentiation-dependent activation. Lyn is a potential regulator of the PI3-K/Akt signaling pathway, as are receptor tyrosine kinases. Protein tyrosine kinase profiling was used to identify two candidate regulators of the PI3-K/Akt pathway, fibroblast growth factor receptor-1 and Sky. At least part of the activation of Akt in differentiating trophoblast giant cells involves an autocrine growth arrest-specific-6-Sky signaling pathway. Inhibition of PI3-K activities via treatment with LY294002 disrupted Akt activation and interfered with the endocrine differentiation of trophoblast giant cells. In summary, activation of the PI3-K/Akt signaling pathway regulates the development of the differentiated trophoblast giant cell phenotype.

Original languageEnglish (US)
Pages (from-to)1469-1481
Number of pages13
JournalMolecular Endocrinology
Issue number7
Publication statusPublished - Jan 1 2002
Externally publishedYes


ASJC Scopus subject areas

  • Molecular Biology
  • Endocrinology

Cite this