PKD1-mediated phosphorylations of VASP are independent of each other.
A, mimicking Ser-157 phosphorylation does not prime for Ser-322 phosphorylation. HeLa cells were transfected with GFP-VASP, GFP-VASP.S157E, or vector control as indicated. Cells were lysed and analyzed by Western blot for phosphorylation at Ser-322 using a phosphospecific antibody. VASP expression was controlled by re-probing with anti-GFP. B, mimicking Ser-322 phosphorylation does not prime for Ser-157 phosphorylation. HeLa cells were transfected with GFP-VASP, GFP-VASP.S322E, or vector control as indicated. Cells were lysed and analyzed by Western blot for phosphorylation at Ser-157 using a phosphospecific antibody. VASP expression was controlled by re-probing with anti-GFP.