Catalytic subunit of protein phosphatase 6 (PP6) ( ). PP6 is a component of a signaling pathway regulating cell cycle progression in response to IL2 receptor stimulation . N-terminal domain restricts G1 to S phase progression in cancer cells, in part through control of cyclin D1 . During mitosis, regulates spindle positioning . Down-regulates MAP3K7 kinase activation of the IL1 signaling pathway by dephosphorylation of MAP3K7 . Participates also in the innate immune defense against viruses by desphosphorylating RIGI, an essential step that triggers RIGI-mediated signaling activation . Also regulates innate immunity by acting as a negative regulator of the cGAS-STING pathway: mediates dephosphorylation and inactivation of CGAS and STING1 (, ). CGAS dephosphorylation at 'Ser-435' impairs its ability to bind GTP, thereby inactivating it .
Subcellular locations: Mitochondrion, Cytoplasm
Ubiquitously expressed in all tissues tested with highest expression levels in testis, heart, kidney, brain, stomach, liver and skeletal muscle and lowest in placenta, lung colon and spleen.