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Co-chaperone
Co-chaperones are proteins that assist chaperone (protein), chaperones in protein folding and other functions. Co-chaperones are the non-client binding molecules that assist in protein folding mediated by Hsp70 and Hsp90. They are particularly essential in stimulation of the ATPase activity of these chaperone proteins. There are a great number of different co-chaperones however based on their domain structure most of them fall into two groups: J-domain proteins and tetratricopeptide repeats (TPR). Co-chaperones assist heat shock proteins in the protein folding process. These co-chaperones can function in a number of ways. Primarily co-chaperones are involved in the ATPase functionality of their associated heat shock proteins. Co-chaperones catalyze the hydrolysis ATP to ADP on their respective chaperones which then allows them undergo a large conformational change that allows them to either bind to their substrates with higher affinity or aid in the release of the substrate followin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hop (protein)
Hop, occasionally written HOP, is an abbreviation for Hsp70-Hsp90 Organizing Protein. It functions as a co-chaperone which reversibly links together the protein chaperones Hsp70 and Hsp90. Hop belongs to the large group of co-chaperones, which regulate and assist the major chaperones (mainly heat shock proteins). It is one of the best studied co-chaperones of the Hsp70/Hsp90-complex. It was first discovered in yeast and homologues were identified in human, mouse, rat, insects, plants, parasites, and virus. The family of these proteins is referred to as STI1 (stress inducible protein) and can be divided into yeast, plant, and animal STI1 (Hop). Synonyms Gene The gene for human Hop is located on chromosome 11q13.1 and consists of 14 exons. Structure STI proteins are characterized by some structural features: All homologues have nine tetratricopeptide repeat (TPR) motifs, that are clustered into domains of three TPRs. The TPR motif is a very common structural feature use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CDC37
Hsp90 co-chaperone Cdc37 is a protein that in humans is encoded by the ''CDC37'' gene. The protein encoded by this gene is highly similar to Cdc 37, a cell division cycle control protein of Saccharomyces cerevisiae. This protein is a HSP90 Co-chaperone with specific function in cell signal transduction. It has been shown to form complex with Hsp90 and a variety of protein kinases including CDK4, CDK6, SRC, RAF1, MOK, as well as eIF-2 alpha kinases. It is thought to play a critical role in directing Hsp90 to its target kinases. Interactions CDC37 has been shown to interact with: * CDK4, * HSP90AA1 * IKBKG, * IKK2, and * STK11. Domain architecture CDC37 consists of three structural domains. The N-terminal domain binds to protein kinases. The central domain is the Hsp90 Hsp90 (heat shock protein 90) is a chaperone protein that assists other proteins to fold properly, stabilizes proteins against heat stress, and aids in protein degradation. It also stabiliz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TOMM70A
Mitochondrial import receptor subunit TOM70 is a protein that in humans is encoded by the ''TOMM70A'' gene. The translocase of outer mitochondrial membrane (TOM) complex is a multisubunit complex involved in the recognition, unfolding, and translocation of preproteins into the mitochondria. See TIM17A (MIM 605057). upplied by OMIMref name="entrez" /> See also * Mitochondria Outer Membrane Translocase * TOMM20 * TOMM22 * TOMM40 Translocase of outer mitochondrial membrane 40 homolog (yeast), also known as TOMM40, is a protein which in humans is encoded by the ''TOMM40'' gene. Function ''TOMM40'' codes for a protein that is embedded into outer membranes of mitochondria ... References Further reading * * * * * * * * * {{gene-3-stub Co-chaperones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hsp70
The 70 kilodalton heat shock proteins (Hsp70s or DnaK) 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. Discovery Members of the Hsp70 family are very strongly upregulated by heat stress and toxic chemicals, particularly heavy metals such as arsenic, cadmium, copper, mercury, etc. Heat shock was originally discovered by Ferruccio Ritossa in the 1960s when a lab worker accidentally boosted the incubation temperature of Drosophila (fruit flies). When ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TOMM34
Mitochondrial import receptor subunit TOM34 is a protein that in humans is encoded by the ''TOMM34'' gene. The protein encoded by this gene is involved in the import of precursor proteins into mitochondria. The encoded protein has a chaperone-like activity, binding the mature portion of unfolded proteins and aiding their import into mitochondria. This protein, which is found in the cytoplasm In cell biology, the cytoplasm is all of the material within a eukaryotic cell, enclosed by the cell membrane, except for the cell nucleus. The material inside the nucleus and contained within the nuclear membrane is termed the nucleoplasm. The ... and sometimes associated with the outer mitochondrial membrane, has a weak ATPase activity and contains 6 TPR repeats. References Further reading * * * * * * * * * * * * * {{gene-20-stub Co-chaperones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BAG4
BAG family molecular chaperone regulator 4 is a protein that in humans is encoded by the ''BAG4'' gene. Function The protein encoded by this gene is a member of the BAG1-related protein family. BAG1 is an anti-apoptotic protein that functions through interactions with a variety of cell apoptosis and growth related proteins including BCL-2, Raf-protein kinase, steroid hormone receptors, growth factor receptors and members of the heat shock protein 70 kDa family. This protein contains a BAG domain near the C-terminus, which could bind and inhibit the chaperone activity of Hsc70/Hsp70. This protein was found to be associated with the death domain of tumor necrosis factor receptor type 1 (TNF-R1) and death receptor-3 (DR3), and thereby negatively regulates downstream cell death signaling. The regulatory role of this protein in cell death was demonstrated in epithelial cells which undergo apoptosis while integrin mediated matrix contacts are lost. Interactions BAG4 has been shown to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SGTA
Small glutamine-rich tetratricopeptide repeat-containing protein alpha is a protein that in humans is encoded by the ''SGTA'' gene. ''SGTA'' orthologs have also been identified in several mammals for which complete genome data are available. Function This gene encodes a protein which is capable of interacting with the major nonstructural protein of parvovirus H-1 and 70-kDa heat shock cognate protein; however, its function is not known. Since this transcript is expressed ubiquitously in various tissues, this protein may serve a housekeeping function. Interactions SGTA has been shown to interact with Growth hormone receptor Growth hormone receptor is a protein that in humans is encoded by the ''GHR'' gene. GHR orthologs have been identified in most mammals. Structure Growth hormone receptor (GHR) is a transmembrane protein consisting of 620 amino acids. The recep .... References Further reading * * * * * * * * * * * * * * * * Co-chaperones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sacsin
Sacsin also known as DnaJ homolog subfamily C member 29 (DNAJC29) is a protein that in humans is encoded by the ''SACS'' gene. Sacsin is a Hsp70 co-chaperone. Function This gene consists of nine exons including a gigantic exon spanning more than 12.8k bp. It encodes the sacsin protein, which includes a UBQ region at the N-terminus, a HEPN domain at the C-terminus and a DnaJ region upstream of the HEPN domain. This modular protein is essential for normal mitochondrial network organization. The gene is highly expressed in the central nervous system, also found in skin, skeletal muscles and at low levels in the pancreas. Mutations in this gene result in autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS), a neurodegenerative disorder characterized by early-onset cerebellar ataxia with spasticity and peripheral neuropathy. Clinical significance Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) is a very rare neurodegenerative A neurodegene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNAJB6
DnaJ homolog subfamily B member 6 is a protein that in humans is encoded by the ''DNAJB6'' gene. Function This gene encodes a member of the DNAJ protein family. DNAJ family members are characterized by a highly conserved amino acid stretch called the 'J-domain' and function as one of the two major classes of molecular chaperones involved in a wide range of cellular events, such as protein folding and oligomeric protein complex assembly. This family member may also play a role in polyglutamine aggregation in specific neurons. Alternative splicing of this gene results in multiple transcript variants; however, not all variants have been fully described. Interactions DNAJB6 has been shown to Protein-protein interaction, interact with keratin 18. It has been also shown that the aggregation of Aβ42 (a process involved in e.g. Alzheimer's disease) is retarded by DNAJB6 in a concentration-dependent manner, extending to very low sub-stoichiometric molar ratios of chaperone to peptid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ST13
Hsc70-interacting protein also known as suppression of tumorigenicity 13 (ST13) is a protein that in humans is encoded by the ''ST13'' gene. Function The protein encoded by this gene is an adaptor protein that mediates the association of the heat shock proteins HSP70 and HSP90. This protein has been shown to be involved in the assembly process of glucocorticoid receptor, which requires the assistance of multiple molecular chaperones. The expression of this gene is reported to be downregulated in colorectal carcinoma tissue suggesting that is a candidate tumor suppressor gene A tumor suppressor gene (TSG), or anti-oncogene, is a gene that regulates a cell during cell division and replication. If the cell grows uncontrollably, it will result in cancer. When a tumor suppressor gene is mutated, it results in a loss or red .... References Further reading * * * * * * * * * * * * * * * * * * {{protein-stub Co-chaperones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
AHSA2
AHSA2 also known as AHA1, activator of heat shock 90kDa protein ATPase homolog 2 (yeast) is a human gene which encodes a protein which acts as co-chaperone of Hsp90 (heat shock protein 90). AHSA2 and the related AHSA1 Activator of 90 kDa heat shock protein ATPase homolog 1 is an enzyme that in humans is encoded by the ''AHSA1'' gene. Interactions AHSA1 has been shown to interact with Heat shock protein 90kDa alpha (cytosolic), member A1 Heat shock protein ... belongs to the AHA (Activator of Hsp90 ATPase) family of stress-regulated proteins that bind directly to Hsp90 and are required for Hsp90-dependent activation of client proteins. References {{protein-stub Co-chaperones ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GrpE
GrpE (''Gro-P'' like protein E) is a bacterial nucleotide exchange factor that is important for regulation of protein folding machinery, as well as the heat shock response. It is a heat-inducible protein and during stress it prevents unfolded proteins from accumulating in the cytoplasm. Accumulation of unfolded proteins in the cytoplasm can lead to cell death. Discovery GrpE is a nucleotide exchange factor that was first discovered by researchers in 1977 as a protein necessary to propagate bacteriophage λ, a virus that infects bacteria by highjacking the bacteria's own replication machinery, in ''Escherichia coli''. By using a genetic screen, researchers knocked out certain genes in E''. coli'' and then tested whether the bacteria was able to replicate, GrpE was found to be crucial to propagation. Since that time, GrpE has been identified in all bacteria and in Archaea where DnaK and DnaJ are present. The crystal structure of GrpE was determined in 1997 at 2.8 Angstrom and id ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
