HSPA1B

Human gene HSPA1B is an intron-less gene which encodes for the heat shock protein HSP70-2, a member of the Hsp70 family of proteins. The gene is located in the major histocompatibility complex, on the short arm of chromosome 6, in a cluster with two paralogous genes, HSPA1A and HSPA1L. HSPA1A and HSPA1B produce nearly identical proteins because the few differences in their DNA sequences are almost exclusively synonymous substitutions or in the three prime untranslated region, heat shock 70kDa protein 1A, from HSPA1A, and heat shock 70kDa protein 1B, from HSPA1B. A third, more modified paralog to these genes exists in the same region, HSPA1L, which shares a 90% homology with the other two.

HSPA1B
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 1HJO, 1S3X, 1XQS, 2E88, 2E8A, 2LMG, 3A8Y, 3ATU, 3ATV, 3AY9, 3D2E, 3D2F, 3JXU, 3LOF, 4IO8, 4J8F, 4PO2, 4WV5, 4WV7, 5AR0, 5AQZ, 3Q49,%%s3D2E
Identifiers
Aliases	HSPA1B, HSP70-1B, HSP70-2, HSP70.2, heat shock protein family A (Hsp70) member 1B, HSX70, HSPA1, HSP70-1, HSP72, HSP70.1
External IDs	OMIM: 603012; MGI: 96244; HomoloGene: 74294; GeneCards: HSPA1B; OMA:HSPA1B - orthologs
Gene location (Human) Chr. Chromosome 6 (human) Band 6p21.33 Start 31,827,738 bp End 31,830,254 bp
Gene location (Mouse) Chr. Chromosome 17 (mouse) Band 17 B1|17 18.51 cM Start 35,188,166 bp End 35,191,132 bp
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in ventricular zone gallbladder ganglionic eminence mucosa of transverse colon gastric mucosa C1 segment Hypothalamus right uterine tube Pituitary Gland substantia nigra Top expressed in corneal stroma conjunctival fornix vestibular membrane of cochlear duct ciliary body plantaris muscle retinal pigment epithelium skin of external ear Ileal epithelium iris esophagus More reference expression data BioGPS n/a
Gene ontology Molecular function nucleotide binding heat shock protein binding signaling receptor binding C3HC4-type RING finger domain binding ATPase activity virus receptor activity histone deacetylase binding protein folding chaperone activity G protein-coupled receptor binding ATP binding enzyme binding ubiquitin protein ligase binding protein binding transcription corepressor activity cadherin binding RNA binding denatured protein binding protein N-terminus binding unfolded protein binding disordered domain specific binding misfolded protein binding Cellular component blood microparticle centriole nucleoplasm inclusion body focal adhesion perinuclear region of cytoplasm ubiquitin ligase complex cytosol extracellular region ficolin-1-rich granule lumen centrosome microtubule organizing center cytoskeleton nucleus cytoplasm mitochondrion endoplasmic reticulum aggresome nuclear speck vesicle extracellular exosome COP9 signalosome protein-containing complex ribonucleoprotein complex Biological process cellular response to oxidative stress regulation of mRNA stability negative regulation of endoplasmic reticulum stress-induced intrinsic apoptotic signaling pathway positive regulation of NF-kappaB transcription factor activity negative regulation of mitochondrial outer membrane permeabilization involved in apoptotic signaling pathway cellular heat acclimation negative regulation of inclusion body assembly positive regulation of tumor necrosis factor-mediated signaling pathway negative regulation of cell death positive regulation of gene expression viral entry into host cell regulation of cell death ATP metabolic process negative regulation of protein ubiquitination negative regulation of extrinsic apoptotic signaling pathway in absence of ligand positive regulation of endoribonuclease activity positive regulation of nucleotide-binding oligomerization domain containing 2 signaling pathway regulation of protein ubiquitination positive regulation of interleukin-8 production regulation of cellular response to heat cellular response to heat negative regulation of transforming growth factor beta receptor signaling pathway positive regulation of proteasomal ubiquitin-dependent protein catabolic process neutrophil degranulation negative regulation of transcription from RNA polymerase II promoter in response to stress protein refolding positive regulation of microtubule nucleation regulation of mitotic spindle assembly mRNA catabolic process response to unfolded protein negative regulation of cell population proliferation negative regulation of cell growth negative regulation of apoptotic process protein stabilization chaperone-mediated protein complex assembly positive regulation of RNA splicing Unfolded Protein Response positive regulation of erythrocyte differentiation chaperone cofactor-dependent protein refolding lysosomal transport response to heat telomere maintenance DNA repair Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 3304 193740 Ensembl ENSG00000232804 ENSG00000224501 ENSG00000212866 ENSG00000204388 ENSG00000231555 n/a ENSMUSG00000091971 UniProt P0DMV8 P0DMV9 Q61696 RefSeq (mRNA) NM_005346 NM_010479 RefSeq (protein) NP_005337 NP_005336 NP_005336 NP_005336.3 NP_005337.2 NP_034609 Location (UCSC) Chr 6: 31.83 – 31.83 Mb Chr 17: 35.19 – 35.19 Mb PubMed search
Wikidata
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Function

Heat shock 70kDa protein 1B is a chaperone protein, cooperating with other heat shock proteins and chaperone systems to maintain proteostasis by stabilizing the structural conformation of other proteins in the cell and protecting against stress-induced aggregation. Hsp70s have also been shown to bind and stabilize mRNA rich in adenine and uracil bases, independent of the occupational states of its other binding sites. This protein is deactivated by binding ATP, and activated by its dephosphorylation to ADP, which requires a potassium ion to facilitate the hydrolysis, or ATP-ADP exchange.

Hsp70-2 specifically is developmentally expressed in male germ line cells during meiosis, where it is necessary for the formation of the complex between CDC2 and cyclin B1. It later becomes incorporated into the CatSper complex, a specialized calcium ion channel that enables spermatozoa motility.

Clinical significance

Infertility has been observed in mice when HSA1B expression is disrupted, as CDC2 in unable to form the required heterodimer with cyclin B1 for the meiotic cell cycle to progress beyond S phase.

Expression of heat shock protein 70kDa protein 2 in transformed tumor cells has been implicated in the rapid proliferation, metastasis, and inhibition of apoptosis in ovarian, bladder urothelial, and breast cancers. Patients with chronic hepatitis B or hepatitis C virus infection who harbor a HSPA1B-1267 single nucleotide polymorphism have a higher risk for developing hepatocellular carcinoma.

Interactions

Interactions have been characterized between Hsp70-2 and the following proteins:

• ATF5,
• BAG1,
• BAG2,
• BAG3,
• CatSperβ,
• CDC2,
• CHCHD3,
• DNAJC7,
• DNAJC8,
• DNAJC9,
• FOXP3,
• HDAC4,
• HOPX,
• HSP40,
• HSP90,
• HSP105,
• IRAK1BP1,
• METTL21A,
• NAA10,
• NEDD1,
• NOD2,
• PPP5C,
• PKRN,
• SMAD3,
• STUB1,
• TERT,
• TRIM5,
• TSC2,

See also

• Heat shock proteins
• Hsp70

External links

• HSPA1B+protein,+human at the U.S. National Library of Medicine Medical Subject Headings (MeSH)

This article incorporates text from the United States National Library of Medicine, which is in the public domain.