STUB1 (STIP1 homology and U-Box containing protein 1) is a human gene that codes for the protein CHIP (C terminus of HSC70-Interacting Protein). [5] [6]
The CHIP protein encoded by this gene binds to and inhibits the ATPase activity of the chaperone proteins HSC70 and HSP70 and blocks the forward reaction of the HSC70-HSP70 substrate-binding cycle. [6] In addition, CHIP possesses E3 ubiquitin ligase activity and promotes ubiquitylation, [7] mainly of chaperone-bound misfolded proteins.
CHIP enhances HSP70 induction during acute stress and also mediates its turnover during the stress recovery process. Hence CHIP appears to maintain protein homeostasis by controlling chaperone levels during stress and recovery. [8]
Mutations in STUB1 cause spinocerebellar ataxia type 16. [9] [ failed verification ]
STUB1 has been shown to interact with:
Ubiquitin is a small (8.6 kDa) regulatory protein found in most tissues of eukaryotic organisms, i.e., it is found ubiquitously. It was discovered in 1975 by Gideon Goldstein and further characterized throughout the late 1970s and 1980s. Four genes in the human genome code for ubiquitin: UBB, UBC, UBA52 and RPS27A.
The 70 kilodalton heat shock proteins are a family of conserved ubiquitously expressed heat shock proteins. Proteins with similar structure exist in virtually all living organisms. Intracellularly localized Hsp70s are an important part of the cell's machinery for protein folding, performing chaperoning functions, and helping to protect cells from the adverse effects of physiological stresses. Additionally, membrane-bound Hsp70s have been identified as a potential target for cancer therapies and their extracellularly localized counterparts have been identified as having both membrane-bound and membrane-free structures.
Heat shock 70 kDa protein 8 also known as heat shock cognate 71 kDa protein or Hsc70 or Hsp73 is a heat shock protein that in humans is encoded by the HSPA8 gene on chromosome 11. As a member of the heat shock protein 70 family and a chaperone protein, it facilitates the proper folding of newly translated and misfolded proteins, as well as stabilize or degrade mutant proteins. Its functions contribute to biological processes including signal transduction, apoptosis, autophagy, protein homeostasis, and cell growth and differentiation. It has been associated with an extensive number of cancers, neurodegenerative diseases, cell senescence, and aging.
Heat shock 70 kDa protein 1, also termed Hsp72, is a protein that in humans is encoded by the HSPA1A gene. As a member of the heat shock protein 70 family and a chaperone protein, it facilitates the proper folding of newly translated and misfolded proteins, as well as stabilize or degrade mutant proteins. In addition, Hsp72 also facilitates DNA repair. Its functions contribute to biological processes including signal transduction, apoptosis, protein homeostasis, and cell growth and differentiation. It has been associated with an extensive number of cancers, neurodegenerative diseases, cell senescence and aging, and inflammatory diseases such as Diabetes mellitus type 2 and rheumatoid arthritis.
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.
BAG family molecular chaperone regulator 1 is a protein that in humans is encoded by the BAG1 gene.
Heat shock protein HSP 90-beta also called HSP90beta is a protein that in humans is encoded by the HSP90AB1 gene.
DnaJ homolog subfamily A member 3, mitochondrial, also known as Tumorous imaginal disc 1 (TID1), is a protein that in humans is encoded by the DNAJA3 gene on chromosome 16. This protein belongs to the DNAJ/Hsp40 protein family, which is known for binding and activating Hsp70 chaperone proteins to perform protein folding, degradation, and complex assembly. As a mitochondrial protein, it is involved in maintaining membrane potential and mitochondrial DNA (mtDNA) integrity, as well as cellular processes such as cell movement, growth, and death. Furthermore, it is associated with a broad range of diseases, including neurodegenerative diseases, inflammatory diseases, and cancers.
Heat shock 70 kDa protein 4 is a protein that in humans is encoded by the HSPA4 gene.
DnaJ homolog subfamily B member 1 is a protein that in humans is encoded by the DNAJB1 gene.
DnaJ homolog subfamily A member 1 is a protein that in humans is encoded by the DNAJA1 gene.
BAG family molecular chaperone regulator 3 is a protein that in humans is encoded by the BAG3 gene. BAG3 is involved in chaperone-assisted selective autophagy.
Ubiquitin-conjugating enzyme E2 D1 is a protein that in humans is encoded by the UBE2D1 gene.
Ubiquitin-conjugating enzyme E2 D2 is a protein that in humans is encoded by the UBE2D2 gene.
Cullin 3 is a protein that in humans is encoded by the CUL3 gene.
Hsp70-binding protein 1 is a protein that in humans is encoded by the HSPBP1 gene.
BAG family molecular chaperone regulator 2 is a protein that in humans is encoded by the BAG2 gene.
BAG family molecular chaperone regulator 5 is a protein that in humans is encoded by the BAG5 gene.
In molecular biology, protein aggregation is a phenomenon in which intrinsically-disordered or mis-folded proteins aggregate either intra- or extracellularly. Protein aggregates have been implicated in a wide variety of diseases known as amyloidoses, including ALS, Alzheimer's, Parkinson's and prion disease.
Chaperone-assisted selective autophagy is a cellular process for the selective, ubiquitin-dependent degradation of chaperone-bound proteins in lysosomes.