BFA1/YJR053W Summary Help

Standard Name BFA1
Systematic Name YJR053W
Alias IBD1
Feature Type ORF, Verified
Description Component of the GTPase-activating Bfa1p-Bub2p complex; involved in multiple cell cycle checkpoint pathways that control exit from mitosis; specifically required when telomeres are damaged, but not for all types of chromosomal DNA damage; phosphorylated by the Polo-like kinase Cdc5p (1, 2, 3 and see Summary Paragraph)
Chromosomal Location
ChrX:534027 to 535751 | ORF Map | GBrowse
Gene Ontology Annotations All BFA1 GO evidence and references
  View Computational GO annotations for BFA1
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 5 genes
Classical genetics
Large-scale survey
232 total interaction(s) for 115 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 10
  • Affinity Capture-RNA: 1
  • Affinity Capture-Western: 19
  • Biochemical Activity: 12
  • Co-localization: 1
  • Reconstituted Complex: 4
  • Two-hybrid: 14

Genetic Interactions
  • Dosage Growth Defect: 1
  • Dosage Rescue: 2
  • Negative Genetic: 82
  • Phenotypic Enhancement: 5
  • Phenotypic Suppression: 2
  • Positive Genetic: 6
  • Synthetic Growth Defect: 25
  • Synthetic Lethality: 29
  • Synthetic Rescue: 19

Expression Summary
Length (a.a.) 574
Molecular Weight (Da) 66,086
Isoelectric Point (pI) 5.69
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrX:534027 to 535751 | ORF Map | GBrowse
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..1725 534027..535751 2011-02-03 1996-07-31
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000003814

BFA1 is a non-essential gene whose product is involved in the spindle checkpoint (4). The spindle checkpoint delays the onset of anaphase in cells with defects in mitotic spindle assembly or in the attachment of chromosomes to the spindle microtubules (see 5 for review; reference 6 describes defects detected by the checkpoint). The checkpoint works by inhibiting the activity of the anaphase promoting complex, thereby preventing the degradation of several cell cycle regulators (5). Like other spindle checkpoint mutants, bfa1 null mutants are sensitive to benomyl and cannot delay cell division in response to spindle depolymerization. Overexpression of BFA1 causes cells to arrest in anaphase (4). Bfa1p and Bub2p localize to the spindle pole body, and appear to act in a branch of the spindle checkpoint pathway that may prevent cytokinesis prior to chromosome segregation (7, 8, 9, 4). Cdh1p, an activator of the anaphase promoting complex, and the protein kinase Dbf2p are likely targets of Bub2p and Bfa1p (7, 8). Genetic evidence suggests that the Bub2p-Bfa1p branch of the spindle checkpoint pathway is distinct from that involving Bub1p, Bub3p, Mad1p, Mad2p, Mad3p, and Mps1p, which may prevent premature chromosome disjunction (5, 7, 8, 9, 4). The C-terminus of Bfa1p has sequence similarity to Byr4p, a negative regulator of cytokinesis in S. pombe. Unlike Byr4p, Bfa1p does not appear to play a role in cytokinesis in the absence of spindle damage (4).

Last updated: 2000-04-04 Contact SGD

References cited on this page View Complete Literature Guide for BFA1
1) Pereira G, et al.  (2000) The Bub2p spindle checkpoint links nuclear migration with mitotic exit. Mol Cell 6(1):1-10
2) Wang Y, et al.  (2000) The Bfa1/Bub2 GAP complex comprises a universal checkpoint required to prevent mitotic exit. Curr Biol 10(21):1379-82
3) Valerio-Santiago M, et al.  (2013) Inhibition of the mitotic exit network in response to damaged telomeres. PLoS Genet 9(10):e1003859
4) Li R  (1999) Bifurcation of the mitotic checkpoint pathway in budding yeast. Proc Natl Acad Sci U S A 96(9):4989-94
5) Hardwick KG  (1998) The spindle checkpoint. Trends Genet 14(1):1-4
6) Hardwick KG, et al.  (1999) Lesions in many different spindle components activate the spindle checkpoint in the budding yeast Saccharomyces cerevisiae. Genetics 152(2):509-18
7) Alexandru G, et al.  (1999) Sister chromatid separation and chromosome re-duplication are regulated by different mechanisms in response to spindle damage. EMBO J 18(10):2707-21
8) Fesquet D, et al.  (1999) A Bub2p-dependent spindle checkpoint pathway regulates the Dbf2p kinase in budding yeast. EMBO J 18(9):2424-34
9) Fraschini R, et al.  (1999) Budding yeast Bub2 is localized at spindle pole bodies and activates the mitotic checkpoint via a different pathway from Mad2. J Cell Biol 145(5):979-91