Translated XBP1s migrates to the nucleus and regulates the transcriptional programs of UPR target genes encoding ER molecular chaperones, folding enzymes, and ER-associated protein degradation (ERAD) components to decrease ER stress.

2021年7月8日 · The spliced form of X-box binding protein 1 (XBP1s) is an active transcription factor that plays a vital role in the unfolded protein response (UPR). Under endoplasmic reticulum (ER) stress, unspliced Xbp1 mRNA is cleaved by the activated stress sensor IRE1α and converted to the mature form e …

2020年7月2日 · With this vignette, we will recap the events that led us to the discovery that the transcription factor XBP1 and a signaling pathway called the unfolded protein response (UPR) are intricately...

Cells overexpressing XBP1(S) exhibit elevated levels of membrane phospholipids, increased surface area and volume of rough ER, and enhanced activity of the cytidine diphosphocholine pathway of phosphatidylcholine biosynthesis. These data suggest that XBP1(S) links the mammalian UPR to phospholipid biosynthesis and ER biogenesis. Introduction

2022年11月8日，中国科学院生物物理研究所的王立堃团队在 Cell Metabolism 期刊在线发表了题为：Cancer cell-intrinsic XBP1 drives immunosuppressive reprogramming of intratumoral myeloid cells by promoting cholesterol production 的研究论文。 该研究发现，肿瘤细胞内IRE1α/XBP1信号通路的活化通过促进自身胆固醇的合成和分泌，抑制抗肿瘤免疫，促进了肿瘤生长。 研究人员首先通过比较TCGA和GTEx数据库中肿瘤组织和正常组织中XBP1 mRNA表达水平，发现肿瘤组织 …

2003年3月3日 · Here we show that UPR-induced splicing of XBP-1 by the transmembrane endonuclease IRE1 is required to restore production of immunoglobulin in XBP-1−/− mouse B cells, providing an integral...

2024年7月25日 · XBP-1s promotes clearance of pathological tau, and loss of function of the ATF-6 branch of the UPR ER prevents XBP-1s rescue of tauopathy in C. elegans. We conducted transcriptomic analysis of...

Xbp1 is activated by splicing of its primary transcript, Xbp1 u, to generate Xbp1 s, a key activator of the endoplasmic reticulum unfolded protein response (UPR ER). We show that Xbp1 s induces the conical UPR ER in the gut, promoting longevity from the resident stem cells.

We demonstrated that the spliced X-box-binding protein-1 (sXBP1) is necessary and sufficient for ER stress-associated miR-346 induction, revealing a novel role for this unfolded protein response-activated transcription factor. In mRNA profiling arrays, we identified 21 mRNAs that were reduced by both ER stress and miR-346.

X-box binding protein 1 (XBP1) is a major, well-conserved component of the unfolded protein response (UPR) that is crucial for glucose homeostasis and lipid metabolism. Metabolic dysfunction has been associated with XBP1 transcriptional activity.