Background：PPM1A（Protein phosphatase 1A） is also named as PPPM1A and belongs to the PP2C family. It is a serine/threonine protein phosphatase that is essential for regulating cellular stress responses in eukaryotes. PPM1A plays an important role in tumor suppression and that it negatively controls many signaling pathways which are critical for trophoblast invasion.（PMID：19404668）. This protein distributes in both the cytoplasm and nucleus of mammalian cells（PMID：9003755）. It has 2 isoforms produced by alternative splicing.
