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* Protein phosphatase 2C signature *
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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).