KAR4 / YCL055W Overview

Standard Name
KAR4 1
Systematic Name
Feature Type
ORF , Verified
Transcription factor required for the mating response; subunit of the mRNA m6A methyltransferase (MIS) complex, regulating meiosis at multiple steps, early prior to pre-meiotic S phase and late during the completion of meiosis and sporulation; exists in two forms, a slower-migrating form abundant during vegetative growth and a faster-migrating pheromone-induced form; null mutant exhibits abnormal lipid metabolic phenotype; homologous to human METTL14, a subunit of a m6A methyltransferase complex 2 3 4 5 6
Name Description
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.

Length (a.a.)
Mol. Weight (Da)
Isoelectric Point
Median Abundance (molecules/cell)
1873 +/- 518
Half-life (min)


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 KAR4 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 response to mating pheromone; subunit of the N6-methyladenosine methyltransferase complex involved in mRNA m6A methylation during meiosis

View computational annotations

Molecular Function

Manually Curated

Cellular Component

Manually Curated


Macromolecular complex annotations are imported from the Complex Portal. These annotations have been derived from physical molecular interaction evidence extracted from the literature and cross-referenced in the entry, or by curator inference from information on homologs in closely related species or by inference from scientific background.

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 shows abnormal vacuolar morphology, a meiotic defect resulting in decreased sporulation, karyogamy, and competitive fitness; null mutant has a defect in N6-methyladenosine (m6A) modification of mRNA during meiosis; reduced function results in abnormal microtubule morphology
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.

104 total interactions for 82 unique genes

Physical Interactions

  • Affinity Capture-MS: 12
  • Affinity Capture-RNA: 3
  • Affinity Capture-Western: 3
  • Co-localization: 1
  • Co-purification: 1
  • PCA: 3
  • Reconstituted Complex: 1
  • Two-hybrid: 7

Genetic Interactions

  • Dosage Lethality: 1
  • Dosage Rescue: 2
  • Negative Genetic: 60
  • Phenotypic Suppression: 5
  • Positive Genetic: 4
  • Synthetic Rescue: 1
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.

KAR4 encodes a transcription factor that lacks overall similarity to known transcription factors, but belongs to the MT-A70 subfamily of methyltransferases. Despite similarities to methyltransferases, Kar4p lacks conserved residues in the S-adenosylmethionine binding site and is unlikely to have methyltransferase activity. In small-scale experiments Kar4p has been shown to bind the promoters of its target genes and to function as a transcriptional activator. In microarray experiments KAR4 displays both positive and negative regulatory effects. Kar4p is required for karyogamy (nuclear fusion during mating), and two well-characterized targets whose transcription is activated by Kar4p in a mating pheromone-dependent manner are KAR3 and CIK1, encoding components of microtubule motors necessary for karyogamy. Other targets include genes involved in other aspects of mating, in the G1/S transition of mitosis, and in meiosis. Expression of Kar4p is regulated on multiple levels. KAR4 transcription is induced in the presence of mating pheromone and during the G1/S transition. Two forms of the protein are expressed, differing by the N-terminal 30 amino acids, and have differing stabilities.
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.