Kazutoshi Mori 교수

Transcription of genes encoding molecular chaperones and folding enzymes in the endoplasmic reticulum (ER) is induced by accumulation of unfolded proteins in the ER. This intracellular signaling, known as the unfolded protein response (UPR), is mediated by the cis-acting ER stress response element (ERSE) in mammals. In addition to ER chaperones, the mammalian transcription factor CHOP (also called GADD153) is induced by ER stress. We report here that the transcription factor XBP-1 (also called T

The accumulation of unfolded proteins in the endoplasmic reticulum (ER) under ER stress conditions activates a series of homoeostatic responses collectively termed the unfolded protein response (UPR). The UPR is unique in which the molecular mechanisms it uses to transmit signals from the ER lumen to the nucleus are completely different to those used for signalling from the plasma membrane. An ER stress signal is sensed and transmitted across the membrane by a transmembrane protein(s) in the ER.

We concluded that Ern4p represents a major component of the putative transcription factor (UPRF) responsible for the UPR leading to the induction of ER-localized stress proteins.

The levels of molecular chaperones and folding enzymes in the endoplasmic reticulum (ER) are controlled by a transcriptional induction process termed the unfolded protein response (UPR). The mammalian UPR is mediated by the cis-acting ER stress response element (ERSE), the consensus sequence of which is CCAAT-N(9)-CCACG. We recently proposed that ER stress response factor (ERSF) binding to ERSE is a heterologous protein complex consisting of the constitutive component NF-Y (CBF) binding to CCAAT

ATF6 is a membrane-bound transcription factor activated by proteolysis in response to endoplasmic reticulum (ER) stress to induce the transcription of ER chaperone genes. We show here that, owing to the presence of intra- and intermolecular disulfide bridges formed between the two conserved cysteine residues in the luminal domain, ATF6 occurs in unstressed ER in monomer, dimer, and oligomer forms. Disulfide-bonded ATF6 is reduced upon treatment of cells with not only the reducing reagent dithiot

Mammalian cells express several transcription factors embedded in the endoplasmic reticulum (ER) as transmembrane proteins that are activated by proteolysis, and two types of these proteins have been extensively investigated. One type comprises the sterol regulatory element-binding proteins (SREBP-1 and SREBP-2). The other type comprises the activating transcription factors 6 (ATF6alpha and ATF6beta), which are activated in response to ER stress. It was shown previously that both SREBP and ATF6

Eukaryotic cells control the levels of molecular chaperones and folding enzymes in the endoplasmic reticulum (ER) by a transcriptional induction process termed the unfolded protein response (UPR) according to the needs within the ER. In Saccharomyces cerevisiae, expression of the UPR-specific transcription factor Hac1p is tightly regulated at the level of mRNA splicing that depends on an unconventional system. Thus, HAC1 precursor mRNA is constitutively expressed but not translated. A sensor mol

When unfolded proteins are accumulated in the endoplasmic reticulum (ER), an intracellular signaling pathway termed the unfolded protein response (UPR) is activated to induce transcription of ER-localized molecular chaperones and folding enzymes in the nucleus. In Saccharomyces cerevisiae, at least six lumenal proteins including essential Kar2p and Pdi1p are known to be regulated by the UPR. We and others recently demonstrated that the basic-leucine zipper protein Hac1p/Ern4p functions as a tran