PPP3CA, also known as protein phosphatase 2B, is a member of the PPP phosphatase family, PP-2B subfamily. It is the alpha catalytic subunit of protein phosphatase 2B (PP2B). PP2B is a holoenzyme that is comprised of a catalytic subunit associated with regulatory subunits. It is a calcium regulated enzyme that is activated by calmodulin and participates in the signaling cascades involved in development of the nervous, cardiovascular, and musculoskeletal systems. PPP3CA activates the T cells of the immune system and can be blocked by drugs. It also activates NFATc (a transcription factor) by dephosphorylating it. The activated NFATc is subsequently translocated into the nucleus, where it upregulates the expression of interleukin 2. PPP3CA interacts with CRTC2, MYOZ1, MYOZ2 and MYOZ3. It also interacts with DNM1L. The interaction dephosphorylates DNM1L and regulates its translocation to mitochondria.