Protein serine/threonine phosphatase

Protein serine/threonine phosphatase (PSP)^[1] is a form of phosphoprotein phosphatase that acts upon serine/threonine residues.

Serine and threonine phosphates are stable under physiological conditions, so a phosphatase has to remove the phosphate to reverse the regulation.

Ser/Thr-specific protein phosphatases are regulated by their location within the cell and by specific inhibitor proteins.

Examples

There are several known groups with numerous members in each:

PPP1 (α, β, γ1, γ2)
PPP2 (formerly 2A)
PPP3 (formerly 2b, also known as calcineurin)
PPP2C
PPP4
PPP5
PPP6

(links are to the catalytic subunit)

All but PPP2C have sequence homology in the catalytic domain, but differ in substrate specificity.

References

^ Shi Y (October 2009). "Serine/threonine phosphatases: mechanism through structure". Cell 139 (3): 468–84. doi:10.1016/j.cell.2009.10.006. PMID 19879837. http://linkinghub.elsevier.com/retrieve/pii/S0092-8674(09)01254-9.

External links

EC 3.1.3.16

Hydrolase: esterases (EC 3.1)

3.1.1: Carboxylic ester hydrolases

Cholinesterase (Acetylcholinesterase, Butyrylcholinesterase) · Pectinesterase · 6-phosphogluconolactonase · PAF acetylhydrolase

Lipase (Bile salt-dependent, Gastric/Lingual, Pancreatic, Lysosomal, Hormone-sensitive, Endothelial, Hepatic, Lipoprotein, Monoacylglycerol, Diacylglycerol)

Phospholipase (A1, A2, B)

3.1.2: Thioesterase

Palmitoyl protein thioesterase · Ubiquitin carboxy-terminal hydrolase L1

3.1.3: Phosphatase

Alkaline phosphatase (ALPI, ALPL, ALPP) · Acid phosphatase (Prostatic)/Tartrate-resistant acid phosphatase/Purple acid phosphatases · Nucleotidase · Glucose 6-phosphatase · Fructose 1,6-bisphosphatase · Calcineurin · Phosphoprotein phosphatase (PP2A) · OCRL · Pyruvate dehydrogenase phosphatase · Fructose 6-P,2-kinase:fructose 2,6-bisphosphatase · PTEN · Phytase · Inositol-phosphate phosphatase (IMPA1)

Phosphoprotein phosphatase: Protein tyrosine phosphatase · Protein serine/threonine phosphatase · Dual-specificity phosphatase

3.1.4: Phosphodiesterase

Autotaxin · Phospholipase (C, D) · Sphingomyelin phosphodiesterase (1) · PDE1 · PDE2 · PDE3 · PDE4A/PDE4B · PDE5 · Lecithinase (Clostridium perfringens alpha toxin) · Cyclic nucleotide phosphodiesterase

3.1.6: Sulfatase

arylsulfatase (Arylsulfatase A, Arylsulfatase B, Arylsulfatase E, Steroid sulfatase) · Galactosamine-6 sulfatase · Iduronate-2-sulfatase · N-acetylglucosamine-6-sulfatase

Nuclease (includes
deoxyribonuclease and
ribonuclease)

3.1.11-16: Exonuclease

Exodeoxyribonuclease	RecBCD

Exoribonuclease	Oligonucleotidase

3.1.21-31: Endonuclease

Endodeoxyribonuclease	Deoxyribonuclease I · Deoxyribonuclease II · Deoxyribonuclease IV · Restriction enzyme · UvrABC endonuclease

Endoribonuclease	RNase III · RNase H (1, 2A, 2B, 2C) · RNase P · RNase A (1, 2, 3, 4/5) · RNase T1 · RNA-induced silencing complex

either deoxy- or ribo-	Aspergillus nuclease S1 · Micrococcal nuclease

B enzm: 1.1/2/3/4/5/6/7/8/10/11/13/14/15-18, 2.1/2/3/4/5/6/7/8, 2.7.10, 2.7.11-12, 3.1/2/3/4/5/6/7, 3.1.3.48, 3.4.21/22/23/24, 4.1/2/3/4/5/6, 5.1/2/3/4/99, 6.1-3/4/5-6

Intracellular signaling peptides and proteins

MAP

see MAP kinase pathway

Calcium

Intracellular calcium-sensing proteins • Calcineurin • Calcium-calmodulin-dependent protein kinase

G protein

Heterotrimeric	cAMP: Heterotrimeric G protein (Gs/Gi) • Adenylate cyclase • cAMP • 3',5'-cyclic-AMP phosphodiesterase • Protein kinase A cGMP: Guanylate cyclase • cGMP • 3',5'-cyclic-GMP phosphodiesterase • Protein kinase G Beta-gamma complex G_β (GNB1, GNB2, GNB3, GNB4, GNB5) • G_γ (GNGT1, GNGT2, GNG2, GNG3, GNG4, GNG5, GNG7, GNG8, GNG10, GNG11, GNG12, GNG13, BSCL2) G protein-coupled receptor kinase • AMP-activated protein kinase

Monomeric	ARFs · Rabs · Ras (HRAS, KRAS, NRAS)

Cyclin

Cyclin-dependent kinase inhibitor protein • Cyclin-dependent kinase • Cyclin

Lipid

Phosphoinositide phospholipase C • Phospholipase c gamma

Other protein kinase

Serine/threonine: Casein kinase (1, 2) • eIF-2 kinase (EIF2AK3) • Glycogen synthase kinase (GSK1, GSK2, GSK-3, GSK3A, GSK3B) • IκB kinase (CHUK, IKK2, IKBKG) • Interleukin-1 receptor-associated kinase (IRAK1, IRAK2, IRAK3, IRAK4) • Lim kinase (LIMK1, LIMK2) • p21 activated kinases (PAK1, PAK2, PAK3, PAK4) • Rho-associated protein kinase (ROCK1, ROCK2) • Ribosomal s6 kinase (RPS6KA1)

Tyrosine: ZAP70 • Focal adhesion protein-tyrosine kinase (PTK2, PTK2B) • BTK

both: Dual-specificity kinase

Other phosphoprotein phosphatase

Serine/threonine: Protein phosphatase 2

Tyrosine: protein tyrosine phosphatase: Receptor-like protein tyrosine phosphatase • Sh2 domain-containing protein tyrosine phosphatase

both: Dual-specificity phosphatase

Apoptosis

see apoptosis signaling pathway

GTP-binding protein regulators

see GTP-binding protein regulators

Other

Activating transcription factor 6 • Signal transducing adaptor protein • I-kappa B protein • Mucin-4 • Olfactory marker protein • Phosphatidylethanolamine binding protein • EDARADD • PRKCSH

see also deficiencies of intracellular signaling peptides and proteins
B trdu: iter (nrpl/grfl/cytl/horl), csrc (lgic, enzr, gprc, igsr, intg, nrpr/grfr/cytr), itra (adap, gbpr, mapk), calc, lipd; path (hedp, wntp, tgfp+mapp, notp, jakp, fsap, hipp, tlrp)