PPP2R1B

PPP2R1B
Identifiers
Aliases	PPP2R1B, PP2A-Abeta, PR65B, protein phosphatase 2 scaffold subunit Abeta
External IDs	OMIM: 603113; MGI: 1920949; GeneCards: PPP2R1B
Gene location (Human)
Chr.	Chromosome 11 (human)
End	111,766,389 bp
Gene location (Mouse)
Chr.	Chromosome 9 (mouse)
End	50,805,529 bp
RNA expression pattern
	Top expressed in
	sperm; ; right lobe of liver; ; left testis; ; right testis; ; adipose tissue; ; body of pancreas; ; islet of Langerhans; ; secondary oocyte; ; abdominal fat; ; subcutaneous adipose tissue;
	Top expressed in
	primitive streak; ; hair follicle; ; fetal liver hematopoietic progenitor cell; ; ureter; ; seminal vesicula; ; white adipose tissue; ; spermatid; ; condyle; ; epithelium of stomach; ; endothelial cell of lymphatic vessel;
	More reference expression data
	; ; ; ;
	More reference expression data
Gene ontology
Molecular function	protein binding; protein serine/threonine phosphatase activity; protein phosphatase regulator activity;
Cellular component	membrane raft; extracellular exosome; protein phosphatase type 2A complex; cytoplasm;
Biological process	apoptotic process involved in morphogenesis; positive regulation of extrinsic apoptotic signaling pathway in absence of ligand; protein dephosphorylation; regulation of phosphoprotein phosphatase activity;
	Sources:Amigo / QuickGO
Orthologs
Databases	NCBI: entry; OMA: entry
	5519
	73699
	ENSG00000137713
	ENSMUSG00000032058
	P30154
	Q7TNP2
	NM_001177562; NM_001177563; NM_002716; NM_181699; NM_181700
	NM_001034085; NM_001286553; NM_028614
	NP_001171033; NP_001171034; NP_002707; NP_859050; NP_859051
	NP_001029257; NP_001273482; NP_082890
	Wikidata
View/Edit Human	View/Edit Mouse

Serine/threonine-protein phosphatase 2A 65 kDa regulatory subunit A beta isoform is an enzyme that in humans is encoded by the PPP2R1B gene.

Function

This gene encodes a constant regulatory subunit of protein phosphatase 2. Protein phosphatase 2 is one of the four major Ser/Thr phosphatases, and it is implicated in the negative control of cell growth and division. It consists of a common heteromeric core enzyme, which is composed of a catalytic subunit and a constant regulatory subunit, that associates with a variety of regulatory subunits. The constant regulatory subunit A serves as a scaffolding molecule to coordinate the assembly of the catalytic subunit and a variable regulatory B subunit. This gene encodes a beta isoform of the constant regulatory subunit A. Defects in this gene could be the cause of some lung and colon cancers. At least two transcript variants encoding different isoforms have been found for this gene.

Discovery

The PPP2R1B gene was discovered as part of the Human Genome Project research center focused on chromosome 11.

Clinical significance

Somatic alterations in PPP2R1B have been identified in colorectal and lung cancer tumors and cell lines, with evidence that these alterations affect protein function, supporting a role for PPP2R1B as a candidate tumor suppressor gene in these cancers. Experimental studies have shown that suppression of PPP2R1B expression enables immortalized human cells to become tumorigenic, and that the wild-type protein forms a complex with the small GTPase RalA. These findings support the role of PPP2R1B as a tumor suppressor involved in regulating RalA function.

A case series described nine cancer patients with germline loss-of-function (LOF) variants in PPP2R1B, with breast cancer being the most frequently observed diagnosis. In all documented cases, individuals also had a family history of cancers including breast, ovarian, prostate, uterine, renal, and colorectal cancer, suggesting that PPP2R1B may function as a predisposition gene in breast and potentially other cancers.

Interactions

PPP2R1B has been shown to interact with:

References

1 2 3 GRCh38: Ensembl release 89: ENSG00000137713 – Ensembl, May 2017
1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000032058 – Ensembl, May 2017
↑ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
↑ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
↑ Hemmings BA, Adams-Pearson C, Maurer F, Müller P, Goris J, Merlevede W, et al. (April 1990). "alpha- and beta-forms of the 65-kDa subunit of protein phosphatase 2A have a similar 39 amino acid repeating structure". Biochemistry. 29 (13): 3166–3173. doi:10.1021/bi00465a002. PMID 2159327.
1 2 Baysal BE, Farr JE, Goss JR, Devlin B, Richard CW (September 1998). "Genomic organization and precise physical location of protein phosphatase 2A regulatory subunit A beta isoform gene on chromosome band 11q23". Gene. 217 (1–2): 107–116. doi:10.1016/S0378-1119(98)00350-3. PMID 9795170.
1 2 "Entrez Gene: PPP2R1B protein phosphatase 2 (formerly 2A), regulatory subunit A, beta isoform".
1 2 Wang SS, Esplin ED, Li JL, Huang L, Gazdar A, Minna J, et al. (October 1998). "Alterations of the PPP2R1B gene in human lung and colon cancer". Science. 282 (5387): 284–287. doi:10.1126/science.282.5387.284. PMID 9765152.
↑ US 6743906, Evans GA, Wang SS, Esplin ED, Li JL, Huang L, "PPP2R1B is a tumor suppressor", issued 1 June 2004, assigned to University of Texas System
↑ Sablina AA, Chen W, Arroyo JD, Corral L, Hector M, Bulmer SE, et al. (June 2007). "The tumor suppressor PP2A Abeta regulates the RalA GTPase". Cell. 129 (5): 969–982. doi:10.1016/j.cell.2007.03.047. PMC 1945132. PMID 17540176.
↑ Mazhar S, O'Connor CM, Harold A, Dowdican AC, Ulintz PJ, Hanson EN, et al. (April 2025). "Germline loss-of-function mutations in PPP2R1B in patients with a personal and family history of cancer". JCI Insight e186288. doi:10.1172/jci.insight.186288. PMC 12129040. PMID 40178903.
1 2 3 4 5 Zhou J, Pham HT, Ruediger R, Walter G (January 2003). "Characterization of the Aalpha and Abeta subunit isoforms of protein phosphatase 2A: differences in expression, subunit interaction, and evolution". The Biochemical Journal. 369 (Pt 2): 387–398. doi:10.1042/BJ20021244. PMC 1223084. PMID 12370081.
1 2 Goudreault M, D'Ambrosio LM, Kean MJ, Mullin MJ, Larsen BG, Sanchez A, et al. (January 2009). "A PP2A phosphatase high density interaction network identifies a novel striatin-interacting phosphatase and kinase complex linked to the cerebral cavernous malformation 3 (CCM3) protein". Molecular & Cellular Proteomics. 8 (1): 157–171. doi:10.1074/mcp.M800266-MCP200. PMC 2621004. PMID 18782753.
↑ Kamibayashi C, Lickteig RL, Estes R, Walter G, Mumby MC (October 1992). "Expression of the A subunit of protein phosphatase 2A and characterization of its interactions with the catalytic and regulatory subunits". The Journal of Biological Chemistry. 267 (30): 21864–21872. doi:10.1016/S0021-9258(19)36692-X. PMID 1328247.
1 2 3 4 5 McCright B, Rivers AM, Audlin S, Virshup DM (September 1996). "The B56 family of protein phosphatase 2A (PP2A) regulatory subunits encodes differentiation-induced phosphoproteins that target PP2A to both nucleus and cytoplasm". The Journal of Biological Chemistry. 271 (36): 22081–22089. doi:10.1074/jbc.271.36.22081. PMID 8703017.

Zolnierowicz S (October 2000). "Type 2A protein phosphatase, the complex regulator of numerous signaling pathways". Biochemical Pharmacology. 60 (8): 1225–1235. doi:10.1016/S0006-2952(00)00424-X. PMID 11007961.
Kamibayashi C, Lickteig RL, Estes R, Walter G, Mumby MC (October 1992). "Expression of the A subunit of protein phosphatase 2A and characterization of its interactions with the catalytic and regulatory subunits". The Journal of Biological Chemistry. 267 (30): 21864–21872. doi:10.1016/S0021-9258(19)36692-X. PMID 1328247.
Tung HY, De Rocquigny H, Zhao LJ, Cayla X, Roques BP, Ozon R (January 1997). "Direct activation of protein phosphatase-2A0 by HIV-1 encoded protein complex NCp7:vpr". FEBS Letters. 401 (2–3): 197–201. Bibcode:1997FEBSL.401..197T. doi:10.1016/S0014-5793(96)01470-6. PMID 9013886. S2CID 23293768.
Adler HT, Nallaseth FS, Walter G, Tkachuk DC (November 1997). "HRX leukemic fusion proteins form a heterocomplex with the leukemia-associated protein SET and protein phosphatase 2A". The Journal of Biological Chemistry. 272 (45): 28407–28414. doi:10.1074/jbc.272.45.28407. PMID 9353299.
Ruediger R, Brewis N, Ohst K, Walter G (November 1997). "Increasing the ratio of PP2A core enzyme to holoenzyme inhibits Tat-stimulated HIV-1 transcription and virus production". Virology. 238 (2): 432–443. doi:10.1006/viro.1997.8873. PMID 9400615.
Wang SS, Esplin ED, Li JL, Huang L, Gazdar A, Minna J, et al. (October 1998). "Alterations of the PPP2R1B gene in human lung and colon cancer". Science. 282 (5387): 284–287. Bibcode:1998Sci...282..284W. doi:10.1126/science.282.5387.284. PMID 9765152.
Takahashi M, Shibata H, Shimakawa M, Miyamoto M, Mukai H, Ono Y (June 1999). "Characterization of a novel giant scaffolding protein, CG-NAP, that anchors multiple signaling enzymes to centrosome and the golgi apparatus". The Journal of Biological Chemistry. 274 (24): 17267–17274. doi:10.1074/jbc.274.24.17267. PMID 10358086.
Campbell IG, Manolitsas T (November 1999). "Absence of PPP2R1B gene alterations in primary ovarian cancers". Oncogene. 18 (46): 6367–6369. doi:10.1038/sj.onc.1203070. PMID 10597236.
Takagi Y, Futamura M, Yamaguchi K, Aoki S, Takahashi T, Saji S (August 2000). "Alterations of the PPP2R1B gene located at 11q23 in human colorectal cancers". Gut. 47 (2): 268–271. doi:10.1136/gut.47.2.268. PMC 1727986. PMID 10896920.
Baysal BE, Willett-Brozick JE, Taschner PE, Dauwerse JG, Devilee P, Devlin B (February 2001). "A high-resolution integrated map spanning the SDHD gene at 11q23: a 1.1-Mb BAC contig, a partial transcript map and 15 new repeat polymorphisms in a tumour-suppressor region". European Journal of Human Genetics. 9 (2): 121–129. doi:10.1038/sj.ejhg.5200585. PMID 11313745.
Ruediger R, Pham HT, Walter G (April 2001). "Alterations in protein phosphatase 2A subunit interaction in human carcinomas of the lung and colon with mutations in the A beta subunit gene". Oncogene. 20 (15): 1892–1899. doi:10.1038/sj.onc.1204279. PMID 11313937.
Yokoyama N, Reich NC, Miller WT (June 2001). "Involvement of protein phosphatase 2A in the interleukin-3-stimulated Jak2-Stat5 signaling pathway". Journal of Interferon & Cytokine Research. 21 (6): 369–378. doi:10.1089/107999001750277844. PMID 11440634.
Elder RT, Yu M, Chen M, Zhu X, Yanagida M, Zhao Y (September 2001). "HIV-1 Vpr induces cell cycle G2 arrest in fission yeast (Schizosaccharomyces pombe) through a pathway involving regulatory and catalytic subunits of PP2A and acting on both Wee1 and Cdc25". Virology. 287 (2): 359–370. doi:10.1006/viro.2001.1007. PMID 11531413.
Yang J, Fan GH, Wadzinski BE, Sakurai H, Richmond A (December 2001). "Protein phosphatase 2A interacts with and directly dephosphorylates RelA". The Journal of Biological Chemistry. 276 (51): 47828–47833. doi:10.1074/jbc.M106103200. PMC 2665282. PMID 11591705.
Strack S, Ruediger R, Walter G, Dagda RK, Barwacz CA, Cribbs JT (June 2002). "Protein phosphatase 2A holoenzyme assembly: identification of contacts between B-family regulatory and scaffolding A subunits". The Journal of Biological Chemistry. 277 (23): 20750–20755. doi:10.1074/jbc.M202992200. PMID 11929880.
Hemmer S, Wasenius VM, Haglund C, Zhu Y, Knuutila S, Franssila K, et al. (April 2002). "Alterations in the suppressor gene PPP2R1B in parathyroid hyperplasias and adenomas". Cancer Genetics and Cytogenetics. 134 (1): 13–17. doi:10.1016/S0165-4608(01)00597-0. PMID 11996789.

[refGRCh38Ensembl-1] 1 2 3 GRCh38: Ensembl release 89: ENSG00000137713 – Ensembl, May 2017

[refGRCm38Ensembl-2] 1 2 3 GRCm38: Ensembl release 89: ENSMUSG00000032058 – Ensembl, May 2017

[3] "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.

[4] "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.

[pmid2159327-5] Hemmings BA, Adams-Pearson C, Maurer F, Müller P, Goris J, Merlevede W, et al. (April 1990). "alpha- and beta-forms of the 65-kDa subunit of protein phosphatase 2A have a similar 39 amino acid repeating structure". Biochemistry. 29 (13): 3166–3173. doi:10.1021/bi00465a002. PMID 2159327.

[pmid9795170-6] 1 2 Baysal BE, Farr JE, Goss JR, Devlin B, Richard CW (September 1998). "Genomic organization and precise physical location of protein phosphatase 2A regulatory subunit A beta isoform gene on chromosome band 11q23". Gene. 217 (1–2): 107–116. doi:10.1016/S0378-1119(98)00350-3. PMID 9795170.

[entrez-7] 1 2 "Entrez Gene: PPP2R1B protein phosphatase 2 (formerly 2A), regulatory subunit A, beta isoform".

[Wang_1998-8] 1 2 Wang SS, Esplin ED, Li JL, Huang L, Gazdar A, Minna J, et al. (October 1998). "Alterations of the PPP2R1B gene in human lung and colon cancer". Science. 282 (5387): 284–287. doi:10.1126/science.282.5387.284. PMID 9765152.

[9] US 6743906, Evans GA, Wang SS, Esplin ED, Li JL, Huang L, "PPP2R1B is a tumor suppressor", issued 1 June 2004, assigned to University of Texas System

[10] Sablina AA, Chen W, Arroyo JD, Corral L, Hector M, Bulmer SE, et al. (June 2007). "The tumor suppressor PP2A Abeta regulates the RalA GTPase". Cell. 129 (5): 969–982. doi:10.1016/j.cell.2007.03.047. PMC 1945132. PMID 17540176.

[11] Mazhar S, O'Connor CM, Harold A, Dowdican AC, Ulintz PJ, Hanson EN, et al. (April 2025). "Germline loss-of-function mutations in PPP2R1B in patients with a personal and family history of cancer". JCI Insight e186288. doi:10.1172/jci.insight.186288. PMC 12129040. PMID 40178903.

[pmid12370081-12] 1 2 3 4 5 Zhou J, Pham HT, Ruediger R, Walter G (January 2003). "Characterization of the Aalpha and Abeta subunit isoforms of protein phosphatase 2A: differences in expression, subunit interaction, and evolution". The Biochemical Journal. 369 (Pt 2): 387–398. doi:10.1042/BJ20021244. PMC 1223084. PMID 12370081.

[pmid18782753-13] 1 2 Goudreault M, D'Ambrosio LM, Kean MJ, Mullin MJ, Larsen BG, Sanchez A, et al. (January 2009). "A PP2A phosphatase high density interaction network identifies a novel striatin-interacting phosphatase and kinase complex linked to the cerebral cavernous malformation 3 (CCM3) protein". Molecular & Cellular Proteomics. 8 (1): 157–171. doi:10.1074/mcp.M800266-MCP200. PMC 2621004. PMID 18782753.

[pmid1328247-14] Kamibayashi C, Lickteig RL, Estes R, Walter G, Mumby MC (October 1992). "Expression of the A subunit of protein phosphatase 2A and characterization of its interactions with the catalytic and regulatory subunits". The Journal of Biological Chemistry. 267 (30): 21864–21872. doi:10.1016/S0021-9258(19)36692-X. PMID 1328247.

[pmid8703017-15] 1 2 3 4 5 McCright B, Rivers AM, Audlin S, Virshup DM (September 1996). "The B56 family of protein phosphatase 2A (PP2A) regulatory subunits encodes differentiation-induced phosphoproteins that target PP2A to both nucleus and cytoplasm". The Journal of Biological Chemistry. 271 (36): 22081–22089. doi:10.1074/jbc.271.36.22081. PMID 8703017.