Phosphotyrosine Interaction Domain Containing Protein 1 (PID1)

The deduced 250-amino acid protein has a calculated molecular mass of 28.27 kD and contains a predicted C-terminal phosphotyrosine-binding domain. RT-PCR analysis confirmed the increased PID1 expression in obese individuals compared to normal weight individuals.

Northern blot analysis detected an approximately 1.5-kb transcript in heart and skeletal muscle with barely detectable expression in brain, colon, thymus, spleen, kidney, liver, small intestine, placenta, lung, and peripheral blood leukocytes. Confocal microscopy localized transfected PID1 to the cytoplasm of 293T and 3T3-L1 cells; the latter cell line displayed PID1 localization to a punctate structure within the cytosol.