Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: UNIPROT:P11021 (
BiP
)
2,049
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
TheBiP protein, a stress response protein, plays an important role in the proper folding and assembly of nascent protein and in the scavenging of misfolded proteins in the endoplasmic reticulum lumen. Translation of
BiP
is directed by an internal ribosomal entry site (IRES) in the 5' nontranslated region of the
BiP
mRNA.
BiP
IRES activity increases when cells are heat stressed. Here we report that
NSAP1
specifically enhances the IRES activity of
BiP
mRNA by interacting with the IRES element. Overexpression of
NSAP1
in 293T cells increased the IRES activity of
BiP
mRNA, whereas knockdown of
NSAP1
by small interfering RNA (siRNA) reduced the IRES activity of
BiP
mRNA. The amount of
NSAP1
bound to the
BiP
IRES increased under heat stress conditions, and the IRES activity of
BiP
mRNA was increased. Moreover, the increase in
BiP
IRES activity with heat treatment was not observed in cells lacking
NSAP1
after siRNA treatment.
BiP
mRNAs were redistributed from the heavy polysome to the light polysome in
NSAP1
knockdown cells. Together, these data indicate that
NSAP1
modulates IRES-dependent translation of
BiP
mRNA through an RNA-protein interaction under heat stress conditions.
...
PMID:BiP internal ribosomal entry site activity is controlled by heat-induced interaction of NSAP1. 1707 7
Eukaryotic gene expression is regulated on different levels ranging from pre-mRNA processing to translation. One of the most characterized families of RNA-binding proteins is the group of hnRNPs: heterogenous nuclear ribonucleoproteins. Members of this protein family play important roles in gene expression control and mRNAs metabolism. In the cytoplasm, several hnRNPs proteins are involved in RNA-related processes and they can be frequently found in two specialized structures, known as GW-bodies (GWbs), previously known as processing bodies: PBs, and stress granules, which may be formed in response to specific stimuli. GWbs have been early reported to be involved in the mRNA decay process, acting as a site of mRNA degradation. In a similar way, stress granules (SGs) have been described as cytoplasmic aggregates, which contain accumulated mRNAs in cells under stress conditions and present reduced or inhibited translation. Here, we characterized the
hnRNP Q
localization after different stress conditions.
hnRNP Q
is a predominantly nuclear protein that exhibits a modular organization and several RNA-related functions. Our data suggest that the nuclear localization of
hnRNP Q
might be modified after different treatments, such as: PMA, thapsigargin, arsenite and heat shock. Under different stress conditions,
hnRNP Q
can fully co-localize with the endoplasmatic reticulum specific chaperone,
BiP
. However, under stress, this protein only co-localizes partially with the proteins: GW182-GWbs marker protein and TIA-1 stress granule component.
...
PMID:Human hnRNP Q re-localizes to cytoplasmic granules upon PMA, thapsigargin, arsenite and heat-shock treatments. 1933 29
