Probable protein phosphatase that may play a role as a mitochondrial signal transduction mediator in pollen germination. May function in retrograde signaling from the mitochondria to the nucleus. May be a downstream factor of cytoplasmic male sterility (CMS). CMS is caused by genetic incompatibility between nuclei and mitochondria within male reproductive organs. H2O + O-phospho-L-seryl-[protein] = L-seryl-[protein] + phosphate H2O + O-phospho-L-threonyl-[protein] = L-threonyl-[protein] + phosphate Binds 2 magnesium or manganese ions per subunit. Highly expressed in mature pollen grains. Expressed in anthers from the bi-cellular to the tri-cellular pollen stage. Plants silencing PP2C13 exhibit a major loss of seed-set fertility, without visible defect in pollen development. Plants silencing PP2C13 show up-regulation of AOX1A gene which is regulated by mitochondrial retrograde signaling. Belongs to the PP2C family. Truncated C-terminus.