Chromosoma

, Volume 119, Issue 5, pp 553–563

Centromere inactivation and epigenetic modifications of a plant chromosome with three functional centromeres

Authors

  • Wenli Zhang
    • Department of HorticultureUniversity of Wisconsin-Madison
  • Bernd Friebe
    • Department of Plant Pathology, Wheat Genetic and Genomic Resources CenterKansas State University
  • Bikram S. Gill
    • Department of Plant Pathology, Wheat Genetic and Genomic Resources CenterKansas State University
    • Department of HorticultureUniversity of Wisconsin-Madison
Research Article

DOI: 10.1007/s00412-010-0278-5

Cite this article as:
Zhang, W., Friebe, B., Gill, B.S. et al. Chromosoma (2010) 119: 553. doi:10.1007/s00412-010-0278-5

Abstract

A chromosome with two functional centromeres is cytologically unstable and can only be stabilized when one of the two centromeres becomes inactivated via poorly understood mechanisms. Here, we report a transmissible chromosome with multiple centromeres in wheat. This chromosome encompassed one large and two small domains containing the centromeric histone CENH3. The two small centromeres are in a close vicinity and often fused as a single centromere on metaphase chromosomes. This fused centromere contained approximately 30% of the CENH3 compared to the large centromere. An intact tricentric chromosome was transmitted to about 70% of the progenies, which was likely a consequence of the dominating pulling capacity of the large centromere during anaphases of meiosis. The tricentric chromosome showed characteristics typical to dicentric chromosomes, including chromosome breaks and centromere inactivation. Remarkably, inactivation was always associated with the small centromeres, indicating that small centromeres are less likely to survive than large ones in dicentric chromosomes. The inactivation of the small centromeres also coincided with changes of specific histone modifications, including H3K27me2 and H3K27me3, of the pericentromeric chromatin.

Supplementary material

412_2010_278_Fig10_ESM.gif (146 kb)
Supplementary Fig. 1

Distribution of H3K27me3 on wheat chromosomes. a H3K27me3 immunofluorescence (red) pattern of a metaphase cell from a plant containing a single mi7BStri chromosome (arrow). b Sequential immunofluorescence assay using anti-CENH3 antibodies (green). The faint green signals at the distal ends of the chromosomes, an example pointed by the arrowhead, were derived from H3K27me3. The H3K27me3 signals were not completely washed off after the first round of immunofluorescence assay. Bar = 10 μm. (GIF 145 kb)

412_2010_278_MOESM1_ESM.tif (4.4 mb)
High-resolution image (TIFF 4543 kb)

Copyright information

© Springer-Verlag 2010