Condensation patterns of prophase/prometaphase chromosome are correlated with H4K5 histone acetylation and genomic DNA contents in plants.

Mitotic prophase chromosome condensation plays an essential role in nuclear division being therefore regulated by highly conserved mechanisms. However, degrees of chromatin condensation in prophase-prometaphase cells may vary along the chromosomes resulting in specific condensation patterns. We examined different condensation patterns (CPs) of prophase and prometaphase chromosomes and investigated their relationship with genome size and distribution of histone H4 acetylated at lysine 5 (H4K5ac) in 17 plant species.

Different patterns of chromosomal histone H3 phosphorylation in land plants.

The chromosomal phosphorylation of histone H3 during mitosis and meiosis seems to play a fundamental role in the control of cell division in all eukaryotes. In plants, the temporal and spatial distribution of H3S10 phosphorylated (H3S10ph) is currently known only for chromosomes of a few angiosperms. In the present study, we analyzed the pattern of H3S10ph in mitotic chromosomes of 14 plant species, including 2 bryophytes and 12 tracheophytes.

Different types of plant chromatin associated with modified histones H3 and H4 and methylated DNA.

Eukaryotic chromosomes are organized into two large and distinct domains, euchromatin and heterochromatin, which are cytologically characterized by different degrees of chromatin compaction during interphase/prophase and by post-synthesis modifications of histones and DNA methylation. Typically, heterochromatin remains condensed during the entire cell cycle whereas euchromatin is decondensed at interphase. However, a fraction of the euchromatin can also remain condensed during interphase and appears as early condensing prophase chromatin.