PPase-2B

PPase-2B is a heterodimeric enzyme composed of a 19kDa calcium-binding subunit and a catalytic subunit (61kDa) that binds calmodulin. PPase-2B was originally identified based on its calcium- and calmodulin-dependent activity toward phosphorylase kinase and inhibitor-1. PPase-2B is identical to the brain protein calcineurin, which constitutes up to 1% of total brain protein. The immunosuppressive drugs FK-506 and cyclosporin A inhibit PPase-2B activity in immune cells, implicating a role for this enzyme in regulation of the immune system. PPase-2B also plays a major role in regulating secretory functions of a varie...

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PPase-2B is a heterodimeric enzyme composed of a 19kDa calcium-binding subunit and a catalytic subunit (61kDa) that binds calmodulin. PPase-2B was originally identified based on its calcium- and calmodulin-dependent activity toward phosphorylase kinase and inhibitor-1. PPase-2B is identical to the brain protein calcineurin, which constitutes up to 1% of total brain protein. The immunosuppressive drugs FK-506 and cyclosporin A inhibit PPase-2B activity in immune cells, implicating a role for this enzyme in regulation of the immune system. PPase-2B also plays a major role in regulating secretory functions of a variety of cells.

PPase-2B is less sensitive to okadaic acid than PPase-2A and PPase-1, requiring micromolar concentrations of okadaic acid for inhibition. It is not inhibited by Inhibitor-1 or Inhibitor-2. Promega PPase-2B is isolated from bovine brain.

References

1. Shenolikar, S. (1994) Ann. Rev. Cell. Biol. 10, 55–86.

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