Histone modifications associated with both A and B chromosomes of maize

Chromosome Res. 2008;16(8):1203-14. doi: 10.1007/s10577-008-1269-8. Epub 2008 Nov 8.

Abstract

We report the distribution of several histone modifications along the arms and in centromeric regions of somatic chromosomes of maize, including the supernumerary B chromosome. Acetylated H3 and H4 as well as H3K4me2, modifications associated with euchromatin, were enriched in the distal parts of the A chromosomes, but were progressively depleted toward the centromeres of the A chromosomes and were depleted in the heterochromatic portions of the B chromosome. Classical histone modifications associated with heterochromatin, including H3K9me2, H3K27me1 and H3K27me2, were distributed throughout both A and B chromosomes. However, H3K27me2 showed a reduced level on the B chromosome compared with the A chromosomes and was not associated with some classes of constitutive heterochromatin. We monitored the presence of each histone modification in the centromeric regions using a YFP-tagged centromere-specific histone, CENH3. We observed the presence of H3K9me2 and absence of H3K4me2 in the centromeric regions of both A and B chromosomes of maize, which is in contrast to the presence of H3K4me2 and absence of H3K9me2 in animal centromeres. These results show a diversity of epigenetic modifications associated with centromeric chromatin in different eukaryotes.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Chromatin / genetics*
  • Chromosomes, Plant / genetics*
  • DNA Primers / genetics
  • Epigenesis, Genetic / genetics*
  • Fluorescent Antibody Technique
  • Histones / genetics*
  • Reverse Transcriptase Polymerase Chain Reaction
  • Species Specificity
  • Zea mays / genetics*

Substances

  • Chromatin
  • DNA Primers
  • Histones