Phorbol 12-myristate 13-acetate is a phorbol ester that is commonly used to activate certain types of PKC, including group A (α, βI, βII, γ) and group B (δ, ε, η, θ) isoforms. 4α-PMA is a structural analog of PMA that does not activate PKC. It is used as a negative control for PMA signaling through PKC.
References:
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[2]. Fischer, S.M., Patrick, K.E., Lee, M.L., et al. 4β- and 4α-12-O-tetradecanoylphorbol-13-acetate elicit arachidonate release from epidermal cells through different mechanisms Cancer Res. 51(3), 850-856 (1991).
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