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- ************************************
- * Protein phosphatase 2C signature *
- ************************************
-
- Protein phosphatase 2C (PP2C) is one of the four major classes of mammalian
- serine/threonine specific protein phosphatases (EC 3.1.3.16). PP2C [1] is a
- monomeric enzyme of about 42 Kd that shows a broad substrate specificity and
- which is dependent on divalent cations (mainly magnesium, but also manganese)
- for its activity. Its exact physiological role in still unclear. Two highly
- related isozymes are currently known in mammals: PP2C-alpha and -beta. In
- yeast there are at least two PP2C homologs: the phosphatase PTC1 [2] which has
- a weak tyrosine phosphatase activity in addition to its activity on serines;
- and YBL0513, a hypothetical yeast protein from chromosome II [3].
-
- PP2C does not seem to be evolutionary related to the main family of serine/
- threonine phosphatases (PP1, PP2A and PP2B). However it is significantly
- similar to the catalytic subunit of pyruvate dehydrogenase phosphatase
- (EC 3.1.3.43) (PDPC) [4], which catalyzes the dephosphorylation and
- concomitant reactivation of the alpha subunit of the E1 component of the
- pyruvate dehydrogenase complex. PDPC is a mitochondrial enzyme and is, like
- PP2C, magnesium-dependent.
-
- As a signature pattern, we selected the best conserved region. It is located
- in the N-terminal part and contains a perfectly conserved tripeptide.
-
- -Consensus pattern: [LIVMFY](2)-[GA]-[LIVM]-[FY]-D-G-H-[GAV]
- -Sequences known to belong to this class detected by the pattern: ALL.
- -Other sequence(s) detected in SWISS-PROT: NONE.
- -Last update: June 1994 / First entry.
-
- [ 1] Wenk J., Trompeter H.-I., Pettrich K.-G., Cohen P.T.W., Campbell D.G.,
- Mieskes G.
- FEBS Lett. 297:135-138(1992).
- [ 2] Maeda T., Tsai A.Y.M., Saito H.
- Mol. Cell. Biol. 13:5408-5417(1993).
- [ 3] Scherens B., El Bakkoury M., Vierendeels F., Dubois E., Messenguy F.
- Yeast 9:1355-1371(1993).
- [ 4] Lawson J.E., Niu X.-D., Browning K.S., Trong H.L., Yan J., Reed L.J.
- Biochemistry 32:8987-8993(1993).
-