The evolution and functional divergence of the histone H2B family in plants
Autoři:
Danhua Jiang aff001; Michael Borg aff001; Zdravko J. Lorković aff001; Sean A. Montgomery aff001; Akihisa Osakabe aff001; Ramesh Yelagandula aff001; Elin Axelsson aff001; Frédéric Berger aff001
Působiště autorů:
Gregor Mendel Institute, Austrian Academy of Sciences, Vienna BioCenter, Dr. Bohr-Gasse, Vienna, Austria
aff001; State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, The Innovative Academy of Seed Design, Chinese Academy of Sciences, Beijing, China
aff002; University of Chinese Academy of Sciences, Beijing, China
aff003
Vyšlo v časopise:
The evolution and functional divergence of the histone H2B family in plants. PLoS Genet 16(7): e32767. doi:10.1371/journal.pgen.1008964
Kategorie:
Research Article
doi:
https://doi.org/10.1371/journal.pgen.1008964
Souhrn
Chromatin regulation of eukaryotic genomes depends on the formation of nucleosome complexes between histone proteins and DNA. Histone variants, which are diversified by sequence or expression pattern, can profoundly alter chromatin properties. While variants in histone H2A and H3 families are well characterized, the extent of diversification of histone H2B proteins is less understood. Here, we report a systematic analysis of the histone H2B family in plants, which have undergone substantial divergence during the evolution of each major group in the plant kingdom. By characterising Arabidopsis H2Bs, we substantiate this diversification and reveal potential functional specialization that parallels the phylogenetic structure of emergent clades in eudicots. In addition, we identify a new class of highly divergent H2B variants, H2B.S, that specifically accumulate during chromatin compaction of dry seed embryos in multiple species of flowering plants. Our findings thus identify unsuspected diverse properties among histone H2B proteins in plants that has manifested into potentially novel groups of histone variants.
Klíčová slova:
Arabidopsis thaliana – Flowering plants – Histones – Chromatin – Nucleosomes – Pollen – Seeds – Sperm
Zdroje
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