BUB2/YMR055C Summary Help

Standard Name BUB2 1
Systematic Name YMR055C
Alias PAC7 2
Feature Type ORF, Verified
Description Mitotic exit network regulator; forms GTPase-activating Bfa1p-Bub2p complex that binds Tem1p and spindle pole bodies, blocks cell cycle progression before anaphase in response to spindle and kinetochore damage (3, 4, 5, 6, 7, 8, 9 and see Summary Paragraph)
Name Description Budding Uninhibited by Benzimidazole 1
Chromosomal Location
ChrXIII:387021 to 386101 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Gene Ontology Annotations All BUB2 GO evidence and references
  View Computational GO annotations for BUB2
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 1 genes
Classical genetics
Large-scale survey
265 total interaction(s) for 137 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 5
  • Affinity Capture-RNA: 2
  • Affinity Capture-Western: 13
  • Biochemical Activity: 2
  • Co-localization: 2
  • Co-purification: 1
  • Reconstituted Complex: 4
  • Two-hybrid: 11

Genetic Interactions
  • Dosage Lethality: 1
  • Dosage Rescue: 3
  • Negative Genetic: 83
  • Phenotypic Enhancement: 17
  • Phenotypic Suppression: 18
  • Positive Genetic: 6
  • Synthetic Growth Defect: 45
  • Synthetic Lethality: 22
  • Synthetic Rescue: 30

Expression Summary
Length (a.a.) 306
Molecular Weight (Da) 35,027
Isoelectric Point (pI) 8.69
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrXIII:387021 to 386101 | ORF Map | GBrowse
Note: this feature is encoded on the Crick strand.
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..921 387021..386101 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 SGDIDS000004659

BUB2 is a non-essential gene whose product is involved in the spindle checkpoint (1, 10). 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 11 for review; reference 12 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 (11). Like other spindle checkpoint mutants, bub2 loss-of-function mutants are sensitive to benomyl and cannot delay cell division in response to spindle depolymerization (1). Bub2p and Bfa1p 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 (13, 14, 3, 15). Cdh1p, an activator of the anaphase promoting complex, and the protein kinase Dbf2p are likely targets of Bub2p and Bfa1p (13, 14). 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 (11, 13, 14, 3, 15).

Last updated: 2000-04-04 Contact SGD

References cited on this page View Complete Literature Guide for BUB2
1) Hoyt MA, et al.  (1991) S. cerevisiae genes required for cell cycle arrest in response to loss of microtubule function. Cell 66(3):507-17
2) Geiser JR, et al.  (1997) Saccharomyces cerevisiae genes required in the absence of the CIN8-encoded spindle motor act in functionally diverse mitotic pathways. Mol Biol Cell 8(6):1035-50
3) 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
4) Pereira G, et al.  (2000) The Bub2p spindle checkpoint links nuclear migration with mitotic exit. Mol Cell 6(1):1-10
5) Krishnan R, et al.  (2000) Saccharomyces cerevisiae BUB2 prevents mitotic exit in response to both spindle and kinetochore damage. Genetics 156(2):489-500
6) Hu F, et al.  (2001) Regulation of the Bub2/Bfa1 GAP complex by Cdc5 and cell cycle checkpoints. Cell 107(5):655-65
7) Pereira G, et al.  (2001) Modes of spindle pole body inheritance and segregation of the Bfa1p-Bub2p checkpoint protein complex. EMBO J 20(22):6359-70
8) Pereira G, et al.  (2002) Regulation of the Bfa1p-Bub2p complex at spindle pole bodies by the cell cycle phosphatase Cdc14p. J Cell Biol 157(3):367-79
9) Molk JN, et al.  (2004) The differential roles of budding yeast Tem1p, Cdc15p, and Bub2p protein dynamics in mitotic exit. Mol Biol Cell 15(4):1519-32
10) Roberts BT, et al.  (1994) The Saccharomyces cerevisiae checkpoint gene BUB1 encodes a novel protein kinase. Mol Cell Biol 14(12):8282-91
11) Hardwick KG  (1998) The spindle checkpoint. Trends Genet 14(1):1-4
12) 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
13) 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
14) Fesquet D, et al.  (1999) A Bub2p-dependent spindle checkpoint pathway regulates the Dbf2p kinase in budding yeast. EMBO J 18(9):2424-34
15) Li R  (1999) Bifurcation of the mitotic checkpoint pathway in budding yeast. Proc Natl Acad Sci U S A 96(9):4989-94