CIT1 / YNR001C Overview

Standard Name
CIT1 1
Systematic Name
CS1 5 , LYS6
Feature Type
ORF , Verified
Mitochondrial citrate synthase; catalyzes condensation of acetyl coenzyme A and oxaloacetate to form citrate, which is the first and rate-limiting step of the TCA cycle; transcription subject to glucose repression; CIT1 has a paralog, CIT2, that arose from the whole genome duplication 1 2 3 4
Name Description
CITrate synthase 1
CIT2 3
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.

CIT1 is located on the right arm of chromosome XIV between the centromere and SUF10 proline tRNA; coding sequence is 1440 nucleotides long with 3 synonymous SNPs; CIT1 has paralog CIT2 from the whole genome duplication
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.

Cit1p is 470 amino acids long, shorter-lived, low-to-moderate in abundance; contains 6 citrate synthase domains; acetylated on 7 lysines, succinylated on 24 lysines, sumoylated on 5 lysines, ubiquitinylated on K237, phosphorylated on 4 residues
Length (a.a.)
Mol. Weight (Da)
Isoelectric Point
Median Abundance (molecules/cell)
11990 +/- 4866
Half-life (hr)


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.

View all CIT1 alleles in SGD search

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.

Mitochondrial citrate synthase involved in citrate metabolism and acetyl-CoA catabolism

View computational annotations

Molecular Function

Manually Curated

Biological Process

Manually Curated

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 mutant displays decreased ability to utilize lactate and acetate carbon sources and is sensitive to rapamycin; in large-scale studies the null mutant displays decreased competitive fitness and chronological lifespan, and sensitivity to various chemicals
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.

Cit1p interacts physically with proteins involved in translation regulation and mitochondrion organization; CIT1 interacts genetically with genes involved in transcription; the cit1 null mutant is viable, the null mutant of paralog cit2 is viable, the cit1 cit2 double mutant is inviable or displays a growth defect.

231 total interactions for 169 unique genes

Physical Interactions

  • Affinity Capture-MS: 40
  • Affinity Capture-RNA: 6
  • Affinity Capture-Western: 2
  • Co-fractionation: 2
  • Proximity Label-MS: 2
  • Reconstituted Complex: 2

Genetic Interactions

  • Dosage Rescue: 1
  • Negative Genetic: 97
  • Phenotypic Enhancement: 8
  • Phenotypic Suppression: 7
  • Positive Genetic: 44
  • Synthetic Growth Defect: 8
  • Synthetic Lethality: 5
  • Synthetic Rescue: 7
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.

CIT1 promoter is bound by Bur6p, Gcn5p, Rgr1p, Spt3p, Spt7p, and Sua7p in response to heat; CIT1 promoter is bound by Fkh1p in response to starvation; CIT1 transcription is upregulated by Hap2p in response to carbon catabolite activation; Cit1 protein activity is activated by Ptc7p; Cit1p protein stability is downregulated by Ucc1p
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.

Summary Paragraph

A summary of the locus, written by SGD Biocurators following a thorough review of the literature. Links to gene names and curated GO terms are included within the Summary Paragraphs.

Last Updated: 2024-07-02

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.