BACKGROUND: Polycomb repressive complexes 1 and 2 play important roles in epigenetic gene regulation by posttranslationally modifying specific histone residues. Polycomb repressive complex 2 is responsible for the trimethylation of lysine 27 on histone H3; Polycomb repressive complex 1 catalyzes the monoubiquitination of histone H2A at lysine 119. Both complexes have been thoroughly studied in Arabidopsis, but the evolution of polycomb group gene families in monocots, particularly those with complex allopolyploid origins, is unknown. RESULTS: Here, we present the in silico identification of the Polycomb repressive complex 1 and 2 (PRC2, PRC1) subunits in allohexaploid bread wheat, the reconstruction of their evolutionary history and a transcriptional analysis over a series of 33 developmental stages. We identified four main subunits of PRC2 [E(z), Su(z), FIE and MSI] and three main subunits of PRC1 (Pc, Psc and Sce) and determined their chromosomal locations. We found that most of the genes coding for subunit proteins are present as paralogs in bread wheat. Using bread wheat RNA-seq data from different tissues and developmental stages throughout plant ontogenesis revealed variable transcriptional activity for individual paralogs. Phylogenetic analysis showed a high level of protein conservation among temperate cereals. CONCLUSIONS: The identification and chromosomal location of the Polycomb repressive complex 1 and 2 core components in bread wheat may enable a deeper understanding of developmental processes, including vernalization, in commonly grown winter wheat.

• Klíčová slova
• Epigenetics, Histone methylation, PRC2, Polycomb repressive complex, Wheat,
• MeSH
• chromozomy rostlin MeSH
• fylogeneze MeSH
• mapování chromozomů MeSH
• molekulární evoluce MeSH
• počítačová simulace MeSH
• PRC1 genetika   MeSH
• PRC2 genetika   MeSH
• pšenice genetika   MeSH
• RNA rostlin MeSH
• sekvenování transkriptomu MeSH
• stanovení celkové genové exprese MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• PRC1 MeSH
• PRC2 MeSH
• RNA rostlin MeSH

Understanding how the packaging of chromatin in the nucleus is regulated and organized to guide complex cellular and developmental programmes, as well as responses to environmental cues is a major question in biology. Technological advances have allowed remarkable progress within this field over the last years. However, we still know very little about how the 3D genome organization within the cell nucleus contributes to the regulation of gene expression. The nuclear space is compartmentalized in several domains such as the nucleolus, chromocentres, telomeres, protein bodies, and the nuclear periphery without the presence of a membrane around these domains. The role of these domains and their possible impact on nuclear activities is currently under intense investigation. In this review, we discuss new data from research in plants that clarify functional links between the organization of different nuclear domains and plant genome function with an emphasis on the potential of this organization for gene regulation.

• Klíčová slova
• 3D Chromatin organization, chromocentres, gene expression, liquid–liquid phase separation (LLPS), nuclear bodies, nuclear domains, nuclear periphery, nucleolus, telomeres, topologically associated domains (TADs),
• MeSH
• buněčné jadérko MeSH
• buněčné jádro * MeSH
• chromatin * MeSH
• regulace genové exprese MeSH
• rostliny genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• chromatin * MeSH