The relationships between the integrin-mediated activation of inward rectifyier K+ channels (K(IR)), the phosphorylation of pp125(FAK) and the rescue of neuritogenesis were studied in 41A3 mouse neuroblastoma cells. Neuritogenesis, elicited by adhesion to FN-enriched substrata, was reversibly impaired by pretreating these cells with the tyrosine kinase inhibitor Herbimycin A. This impairment mimicked that operated by Cs+ ions, which selectively inhibited the integrin-mediated activation of K(IR) channels. Various phosphotyrosine containing cellular proteins underwent a marked increase upon cell adhesion to FN-coated dishes. This increase was significantly reduced by Cs+ addition. Immunoprecipitation of pp125(FAK) revealed that the phosphorylation of this kinase and several associated proteins was significantly and reversibly inhibited by Cs+, indicating that integrin-mediated activation of K(IR) channels is a limiting step upstream to the phosphorylation of pp125(FAK) in the commitment to neuritogenesis.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and biophysical research communications|
|State||Published - May 25 1995|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology