View source for Phosphatase Subfamily PPP4C

[[Phosphatase classification|Phosphatase Classification]]: [[Phosphatase_Fold_MTDP|Fold MTDP]]: [[Phosphatase_Superfamily_MTDP|Superfamily MTDP]]: [[Phosphatase_Family_PPP|Family PPP]]: [[Phosphatase_Subfamily_PPP4C|Subfamily PPP4C]] (catalytic subunit of PP4 holoenzyme)

=== Evolution ===
PPP4C is found in [[Phosphatase_Glossary#Opisthokonta|opisthokonta]], amoebazoa and plants.

=== Domain ===
PPP4C has a single domain - phosphatase domain.

=== Functions ===
PPP4C, catalytic subunit of Protein Phosphatase 4 (PP4) holoenzyme, is closely related to PPP2C, the catalytic subunit of PP2A holoenzyme. Like PP1 and PP2A, holoenzyme PP4 consists of the catalytic subunit and one or two regulatory subunits. At least 6 different holoenzyme complexes have been found. 

Mammal PP4 participates in a number of processes essential for normal cellular physiology, including microtubule organization, homologous recombination (HR)-mediated DNA repair, the DNA damage response, histone modification, apoptosis,  immunoglobulin (Ig) VDJ recombination, pre-TCR signaling, TNF signaling, Toll-like receptor (TLR)-4 signaling, and NF-κB regulation. Germline deletion of PP4 in mice is embryonic lethal, and conditional deletion of PP4 specifically in murine T cells severely impairs T cell development (see introduction in <cite>chen14</cite>). 

PPP4C is implicated in cancer. For instance, high expression of PPP4C is associated with the aggressive malignant behavior of colorectal carcinoma <cite>Li15</cite>.

PP4 dephoshorylate the phophorylated histone 2A variant, γ-H2AX, a marker for DNA damage and cell-cycle arrest. Interestingly, PP2A also dephosphorylates γ-H2AX.

PP4 in ''C. elegans'' is involved in M prophase, perhaps through dephosphorylate SUN-1 protein that is normally phosphorylated during the transition zone and early pachytene <cite>sato-carlton14</cite>.

=== References ===
<biblio>
#chen14 pmid=25215539
#Li15 pmid=25927939
#sato-carlton14 pmid=25340746
</biblio>