Effects of triethyltin bromide on protein phosphorylation in subcellular fractions from rat and rabbit brain

Abstract

Phosphorylation of specific proteins in subcellular fractions of rat brain is affected by the presence of low concentrations (1–50 μM) of triethyltin bromide (Et 3SnBr), in vitro. SDS-PAGE and autoradiography showed that Et 3SnBr increased phosphorylation of an M r = 42,000 protein and an M r = 76,000–80,000 doublet band, but decreased phosphorylation of an M r = 52,000 component. The M r = 42,000 and 76,000–80,000 phosphoproteins have been identified as the α-subunit of pyruvate dehydrogenase (PDH) and synapsin, respectively. Et 3SnBr-induced phosphorylation of rabbit brain PDH results in partial inactivation of the PDH complex.