Histone h3 exerts a key function in mitotic checkpoint control.
It has been firmly established that many interphase nuclear functions, including transcriptional regulation, are regulated by chromatin and histones. How mitotic progression and quality control might be influenced by histones is less well characterized. We show that histone H3 plays a crucial role in activating the spindle assembly checkpoint in response to a defect in mitosis. Prior to anaphase, all chromosomes must attach to spindles emanating from the opposite spindle pole bodies. The tension between sister chromatids generated by the poleward pulling force is an integral part of chromosome biorientation. Lack of tension due to erroneous attachment activates the spindle assembly checkpoint, which corrects the mistakes and ensures segregation fidelity. A histone H3 mutation impairs the ability of yeast cells to activate the checkpoint in a tensionless crisis, leading to missegregation and aneuploidy. The defects in tension sensing result directly from an attenuated H3-Sgo1p interaction essential for pericentric recruitment of Sgo1p. Reinstating the pericentric enrichment of Sgo1p alleviates the mitotic defects. Histone H3, and hence the chromatin, is thus a key factor transmitting the tension status to the spindle assembly checkpoint.
Luo
Jianjun
J
Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA.
Xu
Xinjing
X
Hall
Hana
H
Hyland
Edel M
EM
Boeke
Jef D
JD
Hazbun
Tony
T
Kuo
Min-Hao
MH
D000483:Alleles; D000705:Anaphase / Q000235:genetics / Q000502:physiology; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism*; D043171:Chromosomal Instability; D020090:Chromosome Segregation; D006657:Histones / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D008938:Mitosis; D009154:Mutation / Q000235:genetics / Q000502:physiology; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D008941:Spindle Apparatus / Q000235:genetics / Q000378:metabolism*
D018797:Cell Cycle Proteins; D006657:Histones; D029701:Saccharomyces cerevisiae Proteins