not accumulate late gene RNA transcripts, suggesting that presence of LAP-A alone is not sufficient to induce late gene expression. LAP-A is the first plant aminopeptidase shown to have a regulatory role in signal transduction pathway. Osmoregulation LAP proteins are expressed in a variety of marine organisms as a method of coping with the osmotic threat high salinity poses to the cell. During bouts of high salinity, LAP begins the catalysis of proteins in order to release amino acids into the cell in an attempt to balance the high ion concentrations in the external environment. References Sources External links The MEROPS online database for peptidases and their inhibitors: Animal:M17.001, Bacteria:M17.003, Plant::M17.002. Chemical pathology Tumor markers EC 3.4.11