C. Phosphorylation of ERα in mammalian cells. ERα was co-expressed with the indicated wildtype kinases or kinase‑dead versions in HEK293 cells and immunoprecipitated. Phosphorylation status of ERα was analyzed with an in-gel phosphostain (Pro-Q® Diamond phosphoprotein gel stain, Invitrogen), relative to the whole protein stain (SYPRO®Ruby protein gel stain, Invitrogen). 