XBP1 X-box binding protein 1 P17861 XBP1_HUMAN
Protein Coding Chr 22 22q12.1|22q12 Swiss-Prot reviewed Entrez 7494
Mutations
363
CL 28 · Tissue 333
Samples
132
CL 16 · Tissue 114
Peptides
133
unique mutant peptides
Transcripts
4
isoforms mutated

Stats by Source

Global, split by cell line (COSMIC CL / DepMap / PubMed) vs tissue (COSMIC primary tissue)

How the counts split by source
Stats by Source

Global = all mutations for this gene across every source.

Cell line = COSMIC Cell Lines Project + DepMap + PubMed.

Tissue = COSMIC primary-tissue (patient tumour) samples.

Global can exceed cell line + tissue: COSMIC tissue-derived models sit only in global, and a peptide can be shared across both.

GlobalCell lineTissue
Mutations36328333
Samples13216114
Peptides13313120

Function

XBP1 · X-box binding protein 1

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. [provided by RefSeq, Jul 2008].

Isoforms & Proteins

4 transcripts · UniProt mapping is sequence-verified (AA-safe)

About the isoform mapping
Isoforms & Proteins

Each Ensembl transcript (ENST) this gene is mutated on, with its matched UniProt accession.

The mapping is sequence-verified: the UniProt sequence is identical to the transcript translation, so amino-acid positions line up exactly. A * marks an unreviewed (TrEMBL) entry.

Counts are mutations and unique mutant peptides on each transcript.

TranscriptUniProtMutationsPeptides
ENST00000344347 P17861-2 123 94
ENST00000216037 P17861 89 70
ENST00000403532 B1AHH2* 89 70
ENST00000405219 B1AHH1* 62 51

Gene Properties

Type
Protein Coding
Chromosome
22
Cytoband
22q12.1|22q12
Entrez ID
Aliases
TREB-5TREB5XBP-1XBP2

Recurrent Mutations

Top recurrent amino-acid changes along the protein · needle height = number of mutations

What this lollipop shows
Recurrent Mutations

A lollipop / needle plot – the standard way to show recurrent mutations along a protein (as used by cBioPortal and MutationMapper).

X-axis = amino-acid position in the protein.

Needle height & head size = how often that exact amino-acid change was observed (its recurrence). Tall/large heads are mutational hotspots.

The most recurrent changes are labelled; hover any needle for the change, position and counts.

Mutation Distribution

Where XBP1 is mutated · all tissues, split by cell line vs tissue

Mutation counts by tissue
Mutation Distribution

How many mutations in XBP1 were found in each tissue, across the whole database.

Each bar is a tissue (cell-line and tissue names are merged to the standard tissue), split into cell line and tissue (patient tumour) contributions.

This shows the cancer-context where this gene is recurrently altered.

GTEx Expression

Median TPM across 54 healthy tissues

GTEx Portal ↗
About the expression data
GTEx Expression

Median gene expression (TPM) in normal, non-cancer human tissues from the GTEx project.

Useful for judging tumour specificity – a strong neoantigen target ideally comes from a gene with low expression in healthy tissues.

Scroll or drag the mini-axis below the chart to browse all tissues.

Mutations

All 363 mutations in XBP1

About the mutation list
Mutations

Every mutation record for this gene, across all samples and sources.

The Sample column links to the cell line (cell-line samples) or the tissue type (tissue samples).

Use the Type / Source filters, the search box, and column sorting to explore; each CAN-IMMUNE ID opens the full mutation & peptide view.

IDSampleTranscriptAA Change CDSTypeSourcePeptide