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XBP1

Basics

Aliases:
This biomarker is also known as:
  • XBP-1,
  • TREB5,
  • XBP2,
  • tax-responsive element-binding protein 5,
  • Tax-responsive element-binding protein 5,
  • X-box binding protein 1,
  • X-box-binding protein 1,

Description…

XBP1 is a transcription factor involved in hepatocyte growth, differentiation of plasma cells, immunoglobulin secretion, and the unfolded protein response (UPR). XBP1 regulates MHC class II genes by binding to a promoter element referred to as an X box. XBP1 also plays a role in activating unfolded protein response (UPR) target genes via direct binding to the UPR element (UPRE) during endoplasmic reticulum stress. There is an XBP1 pseudogene on chromosome 5.

Attributes

QA State: Curated
Type: Protein
Short Name:
HGNC Name: XBP1

Datasets

There are no datasets associated with this biomarker.

Organs

The following organs have data associated with this biomarker…

Breast

Attributes

Phase: Two
QA State: Under Review

Overview

XBP1 is also an estrogen-regulated gene and strongly correlates with estrogen receptor alpha (ERα) expression in breast cancers.

Performance Comment

XBP1 was one of numerous potential early detection biomarkers specific to triple-negative breast cancer in multiple pathways identified.

Studies

This biomarker is currently being annotated or is under review. You must be logged in or do not have permission to view any additional information. Contact Heather Kincaid at heather.kincaid@jpl.nasa.gov if you should have access to this biomarker.

Resources

External Resources for XBP1

This gene encodes a transcription factor that regulates MHC class II genes by binding to a promoter element referred to as an X box. This gene product is a bZIP protein, which was also identified as a cellular transcription factor that binds to an enhancer in the promoter of the T cell leukemia virus type 1 promoter. It may increase expression of viral proteins by acting as the DNA binding partner of a viral transactivator. It has been found that upon accumulation of unfolded proteins in the endoplasmic reticulum (ER), the mRNA of this gene is processed to an active form by an unconventional splicing mechanism that is mediated by the endonuclease inositol-requiring enzyme 1 (IRE1). The resulting loss of 26 nt from the spliced mRNA causes a frame-shift and an isoform XBP1(S), which is the functionally active transcription factor. The isoform encoded by the unspliced mRNA, XBP1(U), is constitutively expressed, and thought to function as a negative feedback regulator of XBP1(S), which shuts off transcription of target genes during the recovery phase of ER stress. A pseudogene of XBP1 has been identified and localized to chromosome 5.

Gene

Protein

Other

No other associated resources found.

Biomuta

Mutation Statistics

Gene Name: XBP1
UniProt Accession #: P17861
Mutated Sites Count: 17
Associated Pubmed ID Count 4
CancerDO Count 11
Affected Protein Function Sites Count: 4

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