XBP1 / YIL101C Overview

Standard Name
XBP1 1
Systematic Name
Feature Type
ORF , Verified
Transcriptional repressor; binds promoter sequences of cyclin genes, CYS3, and SMF2; not expressed during log phase of growth, but induced by stress or starvation during mitosis, and late in meiosis; represses 15% of all yeast genes as cells transition to quiescence; important for maintaining G1 arrest and for longevity of quiescent cells; member of Swi4p/Mbp1p family; phosphorylated by Cdc28p; relative distribution to nucleus increases upon DNA replication stress 1 2 3 4 5
Name Description
XhoI site-Binding Protein 1
Comparative Info
Sequence Details


The S. cerevisiae Reference Genome sequence is derived from laboratory strain S288C. Download DNA or protein sequence, view genomic context and coordinates. Click "Sequence Details" to view all sequence information for this locus, including that for other strains.

Protein Details


Basic sequence-derived (length, molecular weight, isoelectric point) and experimentally-determined (median abundance, median absolute deviation) protein information. Click "Protein Details" for further information about the protein such as half-life, abundance, domains, domains shared with other proteins, protein sequence retrieval for various strains, physico-chemical properties, protein modification sites, and external identifiers for the protein.

Phosphorylated by Cdc28p; relative distribution to nucleus increases upon DNA replication stress
Length (a.a.)
Mol. Weight (Da)
Isoelectric Point
Median Abundance (molecules/cell)
903 +/- 708


Curated mutant alleles for the specified gene, listed alphabetically. Click on the allele name to open the allele page. Click "SGD search" to view all alleles in search results. Click "YeastMine" to view all alleles in YeastMine.

View all XBP1 alleles in SGD search | YeastMine

Gene Ontology Details

Gene Ontology

GO Annotations consist of four mandatory components: a gene product, a term from one of the three Gene Ontology (GO) controlled vocabularies (Molecular Function, Biological Process, and Cellular Component), a reference, and an evidence code. SGD has manually curated and high-throughput GO Annotations, both derived from the literature, as well as computational, or predicted, annotations. Click "Gene Ontology Details" to view all GO information and evidence for this locus as well as biological processes it shares with other genes.

Sequence-specific DNA binding transcription factor involved in the repression of transcription by RNA polymerase II in response to various stresses and nutrient limitations; also regulates the cellular transition to quiescence and histone H4 acetylation under DNA damage

View computational annotations

Cellular Component

Manually Curated
Phenotype Details


Phenotype annotations for a gene are curated single mutant phenotypes that require an observable (e.g., "cell shape"), a qualifier (e.g., "abnormal"), a mutant type (e.g., null), strain background, and a reference. In addition, annotations are classified as classical genetics or high-throughput (e.g., large scale survey, systematic mutation set). Whenever possible, allele information and additional details are provided. Click "Phenotype Details" to view all phenotype annotations and evidence for this locus as well as phenotypes it shares with other genes.

Non-essential gene; null mutants have shortened lifespans and decreased resistance to DNA-damaging agent MMS; heterozygous diploid nulls have decreased resistance to carcinogens and various antibiotics; homozygous diploid null mutants are impaired in sporulation and low-nitrogen pseudohyphal growth; overexpression results in increased cell size, abnormal cellular morphology, abnormal cell cycle progression and budding, and slow growth; overexpression in diploids increases invasive growth
Interaction Details


Interaction annotations are curated by BioGRID and include physical or genetic interactions observed between at least two genes. An interaction annotation is composed of the interaction type, name of the interactor, assay type (e.g., Two-Hybrid), annotation type (e.g., manual or high-throughput), and a reference, as well as other experimental details. Click "Interaction Details" to view all interaction annotations and evidence for this locus, including an interaction visualization.

88 total interactions for 77 unique genes

Physical Interactions

  • Affinity Capture-MS: 5
  • Affinity Capture-RNA: 6
  • Affinity Capture-Western: 4
  • Biochemical Activity: 4
  • Co-localization: 1
  • Protein-RNA: 1
  • Reconstituted Complex: 2

Genetic Interactions

  • Dosage Lethality: 1
  • Negative Genetic: 50
  • Phenotypic Enhancement: 1
  • Phenotypic Suppression: 1
  • Positive Genetic: 6
  • Synthetic Growth Defect: 3
  • Synthetic Haploinsufficiency: 1
  • Synthetic Rescue: 2
Regulation Details


The number of putative Regulators (genes that regulate it) and Targets (genes it regulates) for the given locus, based on experimental evidence. This evidence includes data generated through high-throughput techniques. Click "Regulation Details" to view all regulation annotations, shared GO enrichment among regulation Targets, and a regulator/target diagram for the locus.

XBP1 encodes a transcriptional repressor that regulates the cell cycle and binds 5'-YTCGAR-3' motifs in the promoters of target genes. XBP1 is induced during sporulation and reduces the transcription of CLN1 to stimulate sporulation. XBP1 is induced by stress and starvation. Xbp1p regulates DNA double-strand break (DSB) repair via non-homologous end-joining (NHEJ) through regulation of histone H4 acetylation and nucleosome displacement, and physically and genetically interacts with the histone deacetylase Rpd3 complex. Cdc28p phosphorylates Xbp1p at residues Ser146, Ser271 and Ser551. In response to DNA damage, Xbp1p is upregulated in a Mec1-Rad9-Rad53 checkpoint pathway-dependent manner and undergoes dephosphorylation, which promotes its association with the Rpd3 complex and subsequent recruitment to DSBs.
Expression Details


Expression data are derived from records contained in the Gene Expression Omnibus (GEO), and are first log2 transformed and normalized. Referenced datasets may contain one or more condition(s), and as a result there may be a greater number of conditions than datasets represented in a single clickable histogram bar. The histogram division at 0.0 separates the down-regulated (green) conditions and datasets from those that are up-regulated (red). Click "Expression Details" to view all expression annotations and details for this locus, including a visualization of genes that share a similar expression pattern.

Literature Details


All manually curated literature for the specified gene, organized into topics according to their relevance to the gene (Primary Literature, Additional Literature, or Review). Click "Literature Details" to view all literature information for this locus, including shared literature between genes.