Faithful chromosome segregation is required for both mitotic and meiotic cell divisions and is regulated by multiple mechanisms including the anaphase‐promoting complex/cyclosome ( We used a combination of genetic analyses, cytology and immunolocalisation to define the function of At Meiocytes from Our results demonstrate that Arabidopsis
Haspin‐mediated phosphorylation of histone H3 at threonine 3 (H3T3ph) promotes proper deposition of Aurora B at the inner centromere to ensure faithful chromosome segregation in metazoans. However, the function of H3T3ph remains relatively unexplored in plants. Here, we show that in maize (
- NSF-PAR ID:
- 10046419
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- The Plant Journal
- Volume:
- 92
- Issue:
- 6
- ISSN:
- 0960-7412
- Page Range / eLocation ID:
- p. 1121-1131
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary APC /C), which is the largest known E3 ubiquitin‐ligase complex and has been implicated in regulating chromosome segregation in both mitosis and meiosis in animals. However, the role of theAPC /C during plant meiosis remains largely unknown. Here, we show that Arabidopsis is required for male meiosis.APC 8APC 8 in male meiosis.apc8‐1 plants exhibit several meiotic defects including improper alignment of bivalents at metaphase I, unequal chromosome segregation during anaphaseII , and subsequent formation of polyads. Immunolocalisation using an antitubulin antibody showed thatAPC 8 is required for normal spindle morphology. We also observed mitotic defects inapc8‐1, including abnormal sister chromatid segregation and microtubule morphology.APC /C is required for meiotic chromosome segregation and thatAPC /C‐mediated regulation of meiotic chromosome segregation is a conserved mechanism among eukaryotes. -
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De novo centromere formation on chromosome fragments with an inactive centromere in maize (Zea mays)
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