complex(a(GO:"protein phosphatase type 2A complex"), p(HGNC:PPME1))

Components

• a(GO:"protein phosphatase type 2A complex")
• p(HGNC:PPME1)

A portion of cellular PP2A stably associated with PME-1 and was catalytically inactive [80]; intriguingly, this inactive portion of PP2A could be re-activated by PP2A phosphatase activator (PTPA), but not by LCMT1, ruling out the possibility that inactivation was solely caused by demethylation PubMed:19277525

The structural feature that PME-1 binds directly to the PP2A active site, overlapping the binding sites for OA and MCLR, also explains why these phosphatase inhibitors blocked the methylesterase activity of PME-1 PubMed:19277525

Deletion of PTPA homologs in yeast, rrd1/rrd2, resulted in elevated levels of stable PP2A-PME-1 complexes, accompanied by decreased methylation PubMed:19277525

Thus, PME-1 appears to exist in an inactive conformation in the absence of PP2A binding. PubMed:19277525

Structural analysis of the heterotrimeric PME-1-PP2A complex showed that PME-1 is only activated upon binding to PP2A (Figure 4, left panel). PubMed:19277525

Interestingly, although PME-1 is activated by PP2A binding, the catalytic subunit of PP2A is inactivated in this process, not just through demethylation but also by loss of the catalytic metal ions PubMed:19277525

A portion of cellular PP2A stably associated with PME-1 and was catalytically inactive [80]; intriguingly, this inactive portion of PP2A could be re-activated by PP2A phosphatase activator (PTPA), but not by LCMT1, ruling out the possibility that inactivation was solely caused by demethylation PubMed:19277525

Interestingly, although PME-1 is activated by PP2A binding, the catalytic subunit of PP2A is inactivated in this process, not just through demethylation but also by loss of the catalytic metal ions PubMed:19277525

Interestingly, although PME-1 is activated by PP2A binding, the catalytic subunit of PP2A is inactivated in this process, not just through demethylation but also by loss of the catalytic metal ions PubMed:19277525

Furthermore, formation of a stable complex between PP2A and PME-1 likely blocks LCMT1-catalyzed methylation. PubMed:19277525