Abstract
A novel Drosophila protein tyrosine phosphatase gene (dPTP61F) undergoes alternative splicing to encode two non-receptor-like proteins of 61,000 daltons. This splice selection occurs at the 3' end of the message, altering the carboxyl termini of the encoded proteins. These carboxyl-terminal sequences govern the targeting of each protein tyrosine phosphatase either to a cytoplasmic membrane or to the nucleus. The catalytic activity of the two protein products is indistinguishable, suggesting that substrate specificity is modulated by the protein's subcellular location.