SFP1 / YLR403W Overview

Standard Name
SFP1 1
Systematic Name
[ISP(+)] 12 , [ISP+]
Feature Type
ORF , Verified
Regulates transcription of ribosomal protein and biogenesis genes; regulates response to nutrients and stress, G2/M transitions during mitotic cell cycle and DNA-damage response, and modulates cell size; regulated by TORC1 and Mrs6p; sequence of zinc finger, ChIP localization data, and protein-binding microarray (PBM) data, and computational analyses suggest it binds DNA directly at highly active RP genes and indirectly through Rap1p at others; can form the [ISP+] prion 2 3 4 5 6 7 8 9 10 11
Name Description
Split Finger 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)
2241 +/- 927
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 SFP1 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.

RNA polymerase II transcription factor involved in the activation of transcription of ribosomal protein genes and in the regulation of cell size; localizes to both the nucleus and cytoplasm

View computational annotations

Molecular Function

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 mutants grow slowly, have abnormal vacuolar morphology, decreased ethanol tolerance, small cells and nuclei, slow G1 phase progression, abnormal budding, and are sensitive to DNA-damaging agents, caffeine, heat, and various drugs; homozygous diploid nulls tolerate zinc deficiency, cannot sporulate; overexpression slows growth, interferes with silencing, and can be lethal in S288C; overexpression enhances pseudohyphal growth in Sigma1278b
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.

76 total interactions for 62 unique genes

Physical Interactions

  • Affinity Capture-MS: 15
  • Affinity Capture-RNA: 6
  • Affinity Capture-Western: 17
  • Co-localization: 1
  • Co-purification: 1
  • PCA: 1
  • Two-hybrid: 2

Genetic Interactions

  • Dosage Lethality: 4
  • Dosage Rescue: 2
  • Negative Genetic: 9
  • Phenotypic Enhancement: 5
  • Phenotypic Suppression: 3
  • Positive Genetic: 1
  • Synthetic Growth Defect: 4
  • Synthetic Lethality: 5
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.

SFP1 encodes a zinc-coordinating transcription factor of the beta-beta-alpha zinc finger family. Sfp1p regulates the expression of nearly 10% of yeast genes, including those involved in ribosome biogenesis and the regulation of cell size, and can form the amyloid-based [ISP+] prion. Sfp1p activity is regulated by localization to the nucleus, where it activates the transcription of ribosome biogenesis and ribosomal protein genes, likely by controlling the localization of the transcription factors Fhl1p and Ifh1p. Under nutrient limitation or chemical stress, Sfp1p is retained in the cytoplasm by Mrs6p, a component of the secretory pathway. Sfp1p is directly phosphorylated at multiple residues by TORC1, with crosstalk to the PKA pathway. Sfp1p negatively regulates TORC1 phosphorylation of Sch9p, the other key target of TOR in the control of ribosome biogenesis, revealing a negative feedback mechanism that regulates ribosomal protein and ribosome biogenesis gene transcription. Sfp1p remains cytoplasmic when Tor1p is inhibited by rapamycin. In [ISP+] strains, Sfp1p forms aggregates in the nucleus.
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.