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Title: Cohesion and centromere activity are required for phosphorylation of histone H3 in maize
Summary

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 (Zea maysL.) mitotic cells, H3T3ph is concentrated at pericentromeric and centromeric regions. Additional weak H3T3ph signals occur between cohered sister chromatids at prometaphase. Immunostaining on dicentric chromosomes reveals that an inactive centromere cannot maintain H3T3ph at metaphase, indicating that a functional centromere is required for H3T3 phosphorylation. H3T3ph locates at a newly formed centromeric region that lacks detectable CentC sequences and strongly reducedCRMand ZmBs repeat sequences at metaphaseII. These results suggest that centromeric localization of H3T3ph is not dependent on centromeric sequences. In maize meiocytes, H3T3 phosphorylation occurs at the late diakinesis and extends to the entire chromosome at metaphase I, but is exclusively limited to the centromere at metaphaseII. The H3T3ph signals are absent in theafd1(absence of first division) andsgo1(shugoshin) mutants during meiosisIIwhen the sister chromatids exhibit random distribution. Further, we show that H3T3ph is mainly located at the pericentromere during meiotic prophaseIIbut is restricted to the inner centromere at metaphaseII. We propose that this relocation of H3T3ph depends on tension at the centromere and is required to promote bi‐orientation of sister chromatids.

 
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PAR ID:
10046419
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  
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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