MAD1 BASIC INFORMATION
| Standard Name | MAD1 |
|---|---|
| Systematic Name | YGL086W |
| Feature Type | ORF, Verified |
| Description | Coiled-coil protein involved in the spindle-assembly checkpoint; phosphorylated by Mps1p upon checkpoint activation which leads to inhibition of the activity of the anaphase promoting complex; forms a complex with Mad2p (1, 2 and see Summary Paragraph)
|
| Name Description | Mitotic Arrest-Deficient 2, 3 |
| GO Annotations | All MAD1 GO evidence and references |
|---|---|
| View Computational GO annotations for MAD1 | |
| Molecular Function | |
| Manually curated |
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| Biological Process | |
| Manually curated | |
| Cellular Component | |
| Manually curated |
|
| Regulatory Role | |
|---|---|
| Regulatory modules | predicted: cellcycle ( 299 ) |
| Mutant Phenotype | All MAD1 Phenotype details and references |
|---|---|
| Classical genetics | |
| null |
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| unspecified | |
| Large-scale survey | |
| null |
|
| Interactions | MAD1 All interactions details and references |
|---|---|
| 254 total interaction(s) for 139 unique genes/features. | |
| Physical Interactions |
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| Genetic Interactions |
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| External Links | All Associated Seq | Entrez Gene | Entrez RefSeq Protein | MIPS | UniProtKB |
|---|
| Primary SGDID | S000003054 |
|---|
ADDITIONAL INFORMATION for MAD1
SUMMARY PARAGRAPH for MAD1
MAD1 is a non-essential gene that encodes a component of the spindle checkpoint (3, 2). The spindle checkpoint delays the onset of anaphase in cells with defects in mitotic spindle assembly or in the attachment o f chromosomes to the spindle microtubules (see 4 for review; reference 5 describes defects detected by the c heckpoint). The checkpoint works by inhibiting the activity of the anaphase promoting complex, thereby preventing the degradation of several cell cycl e regulators (4). Like other spindle checkpoint mutants, mad1 loss-of-function mutants are sensitive to benomyl and cannot delay cell division in response to spindle depolymerization (3, 2). Mad1p becomes hyperphosphorylated upon spindle depolymerization (2). The essential protein kinase Msp 1p is involved in the spindle checkpoint, and appears to phosphorylate Mad1p (1,6). Mad1p forms a tight complex with another spindle checkpoint protein, Mad2p, throughout the cell cycle (7). Mad1p interacts with Cdc20p, which activates the anaphase promoting complex, in the two-hybrid system, and the presence of Mad1p is required for Mad2 p and Mad3p to interact with Cdc20p (8). Bub1p, Bub3p, Mad1p, Mad2p, Mad3p, and Mps1p act in a branch of the spindle checkpoint pathway that may prevent premature chromosome disjunction. A second branch involves Bub2p and Bfa1p, and may prevent cytokinesis prior to chromosome segregation(9, 10, 11, 12). Homologs of Mad1p act in the spindle checkpoint in Xenopus (Xmad1; 13) and human (MAD1L1; 14).
REFERENCES CITED ON THIS PAGE [View Complete Literature Guide for MAD1]
| 1) | Hardwick KG, et al. (1996) Activation of the budding yeast spindle assembly checkpoint without mitotic spindle disruption. Science 273(5277):953-6 |
| 2) | Hardwick KG and Murray AW (1995) Mad1p, a phosphoprotein component of the spindle assembly checkpoint in budding yeast. J Cell Biol 131(3):709-20 |
| 3) | Li R and Murray AW (1991) Feedback control of mitosis in budding yeast. Cell 66(3):519-31 |
| 4) | Hardwick KG (1998) The spindle checkpoint. Trends Genet 14(1):1-4 |
| 5) | 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 |
| 6) | Weiss E and Winey M (1996) The Saccharomyces cerevisiae spindle pole body duplication gene MPS1 is part of a mitotic checkpoint. J Cell Biol 132(1-2):111-23 |
| 7) | Chen RH, et al. (1999) The spindle checkpoint of budding yeast depends on a tight complex between the Mad1 and Mad2 proteins. Mol Biol Cell 10(8):2607-18 |
| 8) | Hwang LH, et al. (1998) Budding yeast Cdc20: a target of the spindle checkpoint. Science 279(5353):1041-4 |
| 9) | 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 |
| 10) | Fesquet D, et al. (1999) A Bub2p-dependent spindle checkpoint pathway regulates the Dbf2p kinase in budding yeast. EMBO J 18(9):2424-34 |
| 11) | 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 |
| 12) | Li R (1999) Bifurcation of the mitotic checkpoint pathway in budding yeast. Proc Natl Acad Sci U S A 96(9):4989-94 |
| 13) | Chen RH, et al. (1998) Spindle checkpoint protein Xmad1 recruits Xmad2 to unattached kinetochores. J Cell Biol 143(2):283-95 |
| 14) | Jin DY, et al. (1998) Human T cell leukemia virus type 1 oncoprotein Tax targets the human mitotic checkpoint protein MAD1. Cell 93(1):81-91 |





