Protein Phosphatase 6, Regulatory Subunit 3 (PPP6R3)

The variants encode deduced 793- and 791-amino acid proteins, both of which have calculated molecular masses of 89 kD. The first 776 amino acids are identical in the 2 isoforms and include a tandem repeat of ser-thr-asp-ser-glu-glu. Both transcripts have a second putative start methionine that would result in shorter proteins if used. SAPS3 shares significant similarity with yeast Sap190 and Sap185, including conservation of several motifs. Northern blot analysis detected highest expression of 4.9- and 4.1-kb transcripts in skeletal muscle, placenta, heart, pancreas, and testis. Expression was also detected in brain, lung, liver, kidney, spleen, thymus, prostate, small intestine, colon, and leukocytes, but not in ovary. The 4.9-kb transcript predominated in most tissues, but in testis the 4.1-kb transcript was more abundant.