PP2A holoenzyme assembly: in cauda venenum (the sting is in the tail).
Protein phosphatase 2A (PP2A), a major phospho-serine/threonine phosphatase, is conserved throughout eukaryotes. It dephosphorylates a plethora of cellular proteins, including kinases and other signaling molecules involved in cell division, gene regulation, protein synthesis and cytoskeleton organization. PP2A enzymes typically exist as heterotrimers comprising catalytic C-, structural A- and regulatory B-type subunits. The B-type subunits function as targeting and substrate-specificity factors; hence, holoenzyme assembly with the appropriate B-type subunit is crucial for PP2A specificity and regulation. Recently, several biochemical and structural determinants have been described that affect PP2A holoenzyme assembly. Moreover, the effects of specific post-translational modifications of the C-terminal tail of the catalytic subunit indicate that a 'code' might regulate dynamic exchange of regulatory B-type subunits, thus affecting the specificity of PP2A.
Janssens
Veerle
V
Protein Phosphorylation and Proteomics Laboratory, Department of Molecular Cell Biology, Faculty of Medicine, K.U. Leuven, Leuven, Belgium.
Longin
Sari
S
Goris
Jozef
J
D000818:Animals; D002384:Catalysis; D020035:Holoenzymes / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008954:Models, Biological; D011487:Protein Conformation; D054648:Protein Phosphatase 2 / Q000737:chemistry* / Q000378:metabolism*; D017433:Protein Structure, Secondary; D021122:Protein Subunits / Q000737:chemistry / Q000378:metabolism; D013379:Substrate Specificity
D020035:Holoenzymes; D021122:Protein Subunits; D054648:Protein Phosphatase 2