Interaction of folate receptor with signaling molecules lyn and Gα(i-3) in detergent-resistant complexes from the ovary carcinoma cell line IGROV1

Silvia Miotti, Marina Bagnoli, Antonella Tomassetti, Maria Ines Colnaghi, Silvana Canevari

Research output: Contribution to journalArticlepeer-review

Abstract

Using as a model the ovary carcinoma cell line IGROV1, we analyzed the partitioning of the glycosylphosphatidylinositol-anchored folate receptor into lipid rafts based on its relative detergent insolubility, with a focus on physically and functionally associated signaling molecules. A variable amount (40-60%) of folate receptor was found in low-density Triton X-100 insoluble complexes together with subunits of heterotrimeric G-proteins and the src-family non-receptor tyrosine kinases p53-56 lyn. In the same fraction the structural component of caveolae, caveolin, was not detected at the protein level, although the corresponding mRNA was detected in trace amounts. Comodulation of folate receptor and signalling molecules was observed in the detergent-insoluble complexes during cell proliferation or induced by phosphatidylinositol-specific phospholipase C treatment or by interaction with anti-folate receptor monoclonal antibodies. Moreover, complexes of folate receptor, lyn and the Gα(i-3) subunit were immunoprecipitated using either anti-folate receptor or anti-lyn antibodies. In vitro kinase assay of the immunoprecipitates revealed stimulation of phosphorylation of common and specific proteins. In particular, the p53 form of lyn appeared to be enriched and phosphorylated in the anti-folate receptor MOv19 monoclonal antibody immunoprecipitate, whereas a 40 kDa band common to anti-folate receptor and anti-lyn immunoprecipitates was the phosphorylated form of the Gα(i-3) subunit. These findings point to the functional interaction between folate receptor and signaling molecules.

Original languageEnglish
Pages (from-to)349-357
Number of pages9
JournalJournal of Cell Science
Volume113
Issue number2
Publication statusPublished - 2000

Keywords

  • Folate receptor
  • GPI-linked protein
  • Heterotrimeric G protein
  • p53-56 lyn
  • Triton-insoluble domain

ASJC Scopus subject areas

  • Cell Biology

Fingerprint Dive into the research topics of 'Interaction of folate receptor with signaling molecules lyn and Gα(i-3) in detergent-resistant complexes from the ovary carcinoma cell line IGROV1'. Together they form a unique fingerprint.

Cite this