Monopolin is a protein complex that in budding yeast is composed of the four proteins CSM1, HRR25, LRS4, and MAM1. Monopolin is required for the segregation of homologous centromeres to opposite poles of a dividing cell during anaphase I of meiosis.[1] This occurs by bridging DSN1 kinetochore proteins to sister kinetochores within the centromere to physically fuse them and allow for the microtubules to pull each homolog toward opposite mitotic spindles.[2]
Molecular structure
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Monopolin is composed of a 4 CSM1:2 LRS4 complex which forms a V-shaped structure with two globular heads at the ends, which are responsible for directly crosslinking sister kinetochores.[1] Bound to each CSM1 head is a MAM1 protein which recruits one copy of the HRR25 kinase.[3] The hydrophobic cavity on the CSM1 subunit allows the hydrophobic regions of Monopolin receptor and kinetochore protein, DSN1, to bind to and fuse the sister kinetochores.[2]Microtubules can then attach to the kinetochores on the homologous centromeres and pull them toward opposite mitotic spindles to complete anaphase of meiosis I.
Farben and commercially marketed under the trade names, “Motolin” and “Monopolin”. Two more modern alternative fuel additives are ferrocene and methylcyclopentadienyl
850447 Brito IL, Monje-Casas F, Amon A (September 2010). "The Lrs4-Csm1 monopolin complex associates with kinetochores during anaphase and is required for
location at the center of the chromosome. Telomere Chromatid Diploid Monopolin "p + q = Solved, Being the True Story of How the Chromosome Got Its Name"
(October 2016). "Structure of the Saccharomyces cerevisiae Hrr25:Mam1 monopolin subcomplex reveals a novel kinase regulator". The EMBO Journal. 35 (19):
kinetochores occurs during meiosis I because a complex of proteins called monopolins fails to localize to the kinetochore. The involvement of Polo kinases