MBP1 / YDL056W Overview

Standard Name
MBP1 1
Systematic Name
Feature Type
ORF , Verified
Transcription factor; involved in regulation of cell cycle progression from G1 to S phase, forms a complex with Swi6p that binds to MluI cell cycle box regulatory element in promoters of DNA synthesis genes 1
Name Description
MluI-box 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.

Length (a.a.)
Mol. Weight (Da)
Isoelectric Point
Median Abundance (molecules/cell)
1394 +/- 964
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. Click "YeastMine" to view all alleles in YeastMine.

View all MBP1 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 that positively regulates transcription by RNA polymerase II involved in the G1/S transition of mitosis; subunit of the MBF (Mlu1 cell cycle box Binding Factor) transcription complex

View computational annotations

Biological Process

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 mutants have abnormal vacuolar and mitochondrial morphology, respiration defects, decreased ethanol tolerance, increased lifespan and budding index, increased resistance to caffeine and dessication; homozygous diploid nulls are sensitive to heat, tolerant of zinc deficiency; heterozygous diploid nulls are sensitive to starvation; overexpression slows growth, affects cellular morphology and budding
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.

247 total interactions for 169 unique genes

Physical Interactions

  • Affinity Capture-MS: 15
  • Affinity Capture-RNA: 7
  • Affinity Capture-Western: 15
  • Biochemical Activity: 3
  • Co-localization: 2
  • Co-purification: 1
  • PCA: 2
  • Reconstituted Complex: 2
  • Two-hybrid: 5

Genetic Interactions

  • Dosage Growth Defect: 3
  • Dosage Rescue: 6
  • Negative Genetic: 113
  • Phenotypic Enhancement: 4
  • Phenotypic Suppression: 5
  • Positive Genetic: 40
  • Synthetic Growth Defect: 10
  • Synthetic Lethality: 4
  • Synthetic Rescue: 10
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.

Mbp1p is an Ig-fold transcription factor of the Rel subfamily. Mbp1p is a DNA-binding protein that forms MBF complex (Mlu1 cell cycle box [MCB] Binding Factor) with Swi6p. MBF is a sequence-specific transcription factor that regulates gene expression during the G1/S transition of the cell cycle. MBF has over 100 putative targets, with several genes activated or repressed by MBF being involved in DNA synthesis and DNA repair (for example, CDC21, CDC8, and CDC9, and also G1 cyclins). Mbp1p can bind DNA directly without Swi6p. Swi6p does not bind DNA but acts as a trans-activator for MBF function. MBF binds DNA as a single Mbp1p/Swi6p heterodimer in an orientation-independent manner, with the most-often reported MCB consensus sequence being 5'-ACGCGT-3'. The N-terminal region of Mbp1p binds DNA, and the C-terminal region binds Swi6p. The central portion of Mbp1p contains 2 ankyrin repeats separated by a short spacer region. There is physical and genetic evidence that Mbp1p interacts with Skn7p; this complex is distinct from MBF and functions in transcription regulation.
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: 2006-05-15

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.