Disease relevance of Hspa8

• The exposure of the animals to in vivo heat stress was shown to induce the synthesis of otherwise non-existing Hsp72, rendering Hsc70 level unchanged in comparison to unstressed controls [1].
• Hsc73 expression did not differ between strains and was not induced by ischemia [2].
• Escherichia coli DnaK and rat Hsc70 are members of the highly conserved 70-kDa heat shock protein (Hsp70) family that show strong sequence and structure similarities and comparable functional properties in terms of interactions with peptides and unfolded proteins and cooperation with cochaperones [3].
• However, an Hsc70 in which the peptide-binding domain has been replaced by that of DnaK is able to complement this strain for both phenotypes, suggesting that the peptide-binding domain of DnaK is essential to fulfill the specific functions of this protein necessary for growth at high temperatures and for lambda phage replication [3].
• Nuclear translocation of stress protein Hsc70 during S phase in rat C6 glioma cells [4].

Psychiatry related information on Hspa8

• The effects of alcohol consumption and aging on the expression of Hsc70 in the brain were investigated [5].

High impact information on Hspa8

• Together these findings suggest a possible mechanism through which E could influence the activities of progesterone, androgen, and glucocorticoid receptors, by enhancing the expression of Hsc73 in cells where these proteins colocalize [6].
• Incidentally, by examining the primary amino acid sequence of rat, human, and chicken progesterone receptors, we noticed that putative Hsc73 binding sites are conserved across species with similar sites existing in the androgen and glucocorticoid receptors [6].
• Quantitative in situ hybridization analysis of brains from naturally cycling female rats revealed a significant increase in Hsc73 mRNA in the VMH and arcuate nucleus of animals during proestrus compared with those at diestrus-1 [6].
• The 70-kDa heat shock cognate protein (Hsc73) gene is enhanced by ovarian hormones in the ventromedial hypothalamus [6].
• To confirm that these increases were steroid hormone dependent, we compared vehicle-treated ovariectomized females with ovariectomized females treated with estradiol benzoate and P. Northern analysis and in situ hybridizations showed that the Hsc73 gene is enhanced by E and P in the pituitary and subregions of the VMH [6].

Biological context of Hspa8

• Characterization and mapping of a highly conserved processed pseudogene and an intron-carrying gene of the heat shock cognate protein 70 (Hsc70) gene family in the rat [7].
• A processed pseudogene of the rat Hsc70 gene, Hsc70-ps1, is described, which still presents the open reading frame of the original gene [7].
• Both Hsc70 (p73) and Hsp70 (p72) were demonstrated to exert this effect through a mechanism that appears to be independent of both redox, and phosphorylation state [8].
• Maximal cellular Hsc70 content (170% of the control) was observed in early to mid S phase followed by a drastic decline while cells pass through G2/M (20% of the control) [4].
• The expression and the nuclear translocation of the constitutive heat shock protein 70 (Hsc70) were determined during the cell cycle in synchronized rat astrocytomic C6 glioma cells [4].

Anatomical context of Hspa8

• In dissociated hippocampal neurons, both Hsp70 and Hsc70 immunoreactivities are distributed throughout the soma and dendrites [9].
• Immunohistochemical studies show that expression of Hsc70 is high, but that of Hsp70 is low, in the cerebral cortex and hippocampal formation [9].
• Constitutively expressed heat shock proteins Hsp90, Hsc70, Hsp60, and Hsp40 and a range of neurotransmitter receptors are present in lipid rafts isolated from rat forebrain and cerebellum [10].
• Following heating at 43 degrees C for 2 hours, Hsc70 binds to isolated nuclear matrices and isolated nuclei, probably because of the increased exposure of hydrophobic domains [11].
• Hsc70 mRNAs and proteins were present in all cell types, again with the highest concentrations being present in microglia [12].

Associations of Hspa8 with chemical compounds

• These results indicate a role for Hsc70 but not for Hsp70 in the process of S phase entry and/or progression in C6 cells under physiological conditions [4].
• Single crystals of recombinant 10 kDa subdomain of rat Hsc70 have been obtained using ammonium sulfate as a precipitant at room temperature [13].

Other interactions of Hspa8

• Immediately after the stress only Hsc70 was found in association with glucocorticoid receptor [14].
• In primary cultures and brain tissue, the increased Hsp70 mRNA levels were still more than 500-fold less than constitutive Hsc70 mRNA and 50-fold less than Hsp60 levels [15].
• This cell line exhibits an aberrant heat shock response which is characterized by a lack of the inducible Hsp70 isoform, even under conditions of heat or hydrogen peroxide stress, while the constitutively expressed Hsc70 and the inducible isoform of hemoxygenase (HO-1) are strongly enhanced by heat stress (43.5 degrees C; 30 min) [16].
• Characteristics of the interaction between Hsc70 and the transferrin receptor in exosomes released during reticulocyte maturation [17].

Analytical, diagnostic and therapeutic context of Hspa8

• Upon gel filtration, Hsc70 was found to exist as a mixture of monomers, dimers, and oligomers, but the 60-kDa fragment was predominantly found to exist as monomers [18].
• Hsc70 was weakly induced after treatment, and dj3 was little induced [19].
• Western blot analysis with different monoclonal antibodies showed that only the constitutively expressed and moderately stress-activated Hsc70 is induced during serum stimulation [4].
• Affinity chromatography confirmed direct interaction of isolated Hip fragments and protein fusions bearing this region with the ATPase domain of Hsc70 in an ATP- and salt-dependent manner [20].
• Immunoprecipitation experiments showed that rDJL interacted with Hsc70 and clathrin protein [21].

References