Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P11021 (BiP)
 2,049 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We previously reported that the spermatid-specific transcription factor Tisp40 functions through UPRE and CRE. To investigate Tisp40 function in vivo, we generated TISP40(-/-) mice. TISP40(-/-) mice were born at expected ratios, were healthy, and mutant males bred normally. However, the ER stress-response protein Grp78/BiP accumulated in the TISP40(-/-) testis and RAMP4 (Ribosome-associated membrane protein 4) mRNA level was up-regulated. Disruption of TISP40 caused ER stress and activation of caspase 12 but not caspase 9, leading to apoptosis of meiotic/postmeiotic germ cells. On the other hand, DAPI staining and electron microscopy revealed that epididymal sperm nuclei were abnormally relaxed in the TISP40(-/-) testis, a phenotype that was independent of the expression and maturation of transition proteins and protamines but due to abnormally retained histones. Histones localized to the cytoplasm as well as to the nucleus and were also retained in epididymal sperm. Histones H2A and H4 were dramatically up-regulated and the acetylation of H2A, H2B and H4 was also enhanced in the TISP40(-/-) testis. Taken together, we conclude that Tisp40 plays an important role in the unfolded protein response of the testis and in regulating the maturation of sperm head nuclei.
 ...
PMID:The testes-specific bZip type transcription factor Tisp40 plays a role in ER stress responses and chromatin packaging during spermiogenesis. 1699 36

Human DNAJC12 is a J domain-containing protein whose regulation, subcellular localization, and function are currently unknown. We show here that the abundance of DNAJC12 in human LNCaP prostate cancer cells is upregulated by the stress-inducing drug A23187 and by the stressregulated transcription factor AIbZIP/CREB3L4. The DNAJC12 gene encodes two isoforms, only one of which (isoform a) is expressed in these cells. Immunofluorescence studies showed that a recombinant DNAJC12 protein is diffusely distributed in the cytoplasm. To identify substrates of DNAJC12, we used an immunoaffinity-mass spectrometry approach in cells that express epitope-tagged DNAJC12. The list of potential DNAJC12-binding proteins that were identified in this screen includes several nucleotide-binding proteins. The most frequently identified partner of DNAJC12 in unstressed cells was Hsc70, a cognate Hsp70 chaperone, whereas in stressed cells, the ER chaperone BiP was frequently associated with DNAJC12. Immunoprecipitation experiments confirmed that the endogenous DNAJC12 and Hsc70 proteins interact in LNCaP cells. These results clarify the role of DNAJC12 in the regulation of Hsp70 function.
 ...
PMID:The co-chaperone DNAJC12 binds to Hsc70 and is upregulated by endoplasmic reticulum stress. 2412 53