Fig. 2.

Tyrosine phosphorylation of human tensin1. A, HEK293 cells were transfected to express S-tag tensin1 and either not treated as control (C) or treated for 30 min with 1 mm peroxyvanadate (PV) to inhibit endogenous PTPs. S-protein beads were used to recover S-tag tensin1, which was immunoblotted with anti-pTyr antibody to show increased tyrosine phosphorylation with peroxyvanadate treatment and anti-S-tag antibody to show equal recovery of S-tag tensin1. B, Peptide sequences and phosphorylated residues in tensin1 recovered from cells pre-treated with peroxyvanadate, as identified by mass spectrometry. C, Schematic showing the central location of the 10 Tyr phosphorylation sites identified in human tensin1 by mass spectrometry.