Shiaw-Der YangJau-Song YuZin-Der Wen2021-05-172021-05-171994https://scholars.lib.ntu.edu.tw/handle/123456789/560925The signal transducrion mechanism of protein kinase FA/GSK‐3α by tyrosine phosphorylation in A431 cells was investigated. Kinase FA/GSK‐3α was found to exist in a highly tyrosine‐phosphorylated/activated state in resting cells but could be tyrosine‐dephosphorylated and inactivated to ∼60% of the control level when cells were acutely treated with 1 μM tumor phorbol ester (TPA) at 37oC for 30 min, as demonstrated by metabolic 32P‐labeling the cells, followed by immunoprecipitation and two‐dimensional phosphoamino acid analysis and by immunodetection in an antikinase FA/GSK‐3α immunoprecipitate kinase assay.enjournal article10.1002/jcb.240560416.