Induction of the mammalian GRP78/BiP gene by Ca2+ depletion and formation of aberrant proteins: activation of the conserved stress-inducible grp core promoter element by the human nuclear factor YY1.
AUTOR(ES)
Li, W W
RESUMO
Previously, we have identified a constitutive nuclear factor, p70CORE, from HeLa cell nuclear extract which interacts specifically with the stress-inducible change region (SICR) of the grp78 promoter. Here we report that p70CORE is identical to YY1, a member of the GLI zinc finger family, by criteria of biochemical properties including apparent molecular weight, binding site homology, immunoreactivity, and affinity purification. Recombinant YY1 binds the double-stranded SICR with high specificity but has no affinity for its single-stranded form. In cotransfection studies, YY1 specifically enhanced the transcriptional activation of the grp78 promoter under a variety of stress conditions: depletion of the endoplasmic reticulum calcium stores, protein glycosylation block, and formation of aberrant proteins by azetidine treatment. In contrast, YY1 has minimal effect on the stress induction of the hsp70 promoter. YY1 enhancement of the grp78 stress response is dependent on its DNA-binding domain, with little effect on the basal expression of the promoter. The effect of YY1 transactivation may be mediated by the highly conserved grp78 core element. This is the first example of the ubiquitous factor YY1 involved in regulating inducible gene expression and its involvement in mediating stress signals generated from the endoplasmic reticulum to the nucleus.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=231729Documentos Relacionados
- Stress induction of the mammalian GRP78/BiP protein gene: in vivo genomic footprinting and identification of p70CORE from human nuclear extract as a DNA-binding component specific to the stress regulatory element.
- Inhibition of tumor progression by suppression of stress protein GRP78/BiP induction in fibrosarcoma B/C10ME.
- Transduction of calcium stress through interaction of the human transcription factor CBF with the proximal CCAAT regulatory element of the grp78/BiP promoter.
- Role of GRP78/BiP Degradation and ER Stress in Deoxynivalenol-Induced Interleukin-6 Upregulation in the Macrophage
- The mammalian endoplasmic reticulum stress response element consists of an evolutionarily conserved tripartite structure and interacts with a novel stress-inducible complex.