Tensin2 reduces intracellular phosphatidylinositol 3,4,5-trisphosphate levels at the plasma membrane
2010 (English)In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 399, no 3, 396-401 p.Article in journal (Refereed) Published
Tensins are proposed cytoskeleton-regulating proteins. However, Tensin2 additionally inhibits Akt signalling and cell survival. Structural modelling of the Tensin2 phosphatase (PTPase) domain revealed an active site-like pocket receptive towards phosphoinositides. Tensin2-expressing HEK293 cells displayed negligible levels of plasma membrane phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P-3) under confocal microscopy. However, mock-transfected cells, and Tensin2 cells harbouring a putative phosphatase-inactivating mutation, exhibited significant PtdIns(3,4,5)P-3 levels, which decreased upon phosphatidylinositol 3-kinase inhibition with LY294002. In contrast, wtTensin3, mock and mutant cells were identical in membrane PtdIns(3,4,5)P-3 and Akt phosphorylation. In vitro lipid PTPase activity was however undetectable in isolated recombinant PTPase domains of both Tensins, indicating a possible loss of structural stability when expressed in isolation. In summary, we provide evidence that Tensin2, in addition to regulating cytoskeletal dynamics, influences phosphoinositide-Akt signalling through its PTPase domain.
Place, publisher, year, edition, pages
2010. Vol. 399, no 3, 396-401 p.
Tensin, Phosphatase, PTEN, Phosphoinositide, Integrin, Cytoskeleton
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-135022DOI: 10.1016/j.bbrc.2010.07.085ISI: 000281587400015PubMedID: 20678486OAI: oai:DiVA.org:uu-135022DiVA: diva2:374305