Non-Rabl chromosome organization in endoreduplicated nuclei of barley embryo and endosperm tissues

Nowicka A., Ferková L., Said M., Kovačik M., Zwyrtková J., Baroux C., Pečinka A.

Klíčová slova: Barley, CENH3, CEREBA repeat, embryo, endoreduplication, endosperm, Hordeum vulgare, nuclear organization, Rabl configuration
Abstrakt: Rabl organization is a type of interphase chromosome arrangement with centromeres and telomeres clustering at opposite nuclear poles. Here, we analyzed nuclear morphology and chromosome organization in cycling and endoreduplicated nuclei isolated from embryo and endosperm tissues of developing barley seeds. We show that endoreduplicated nuclei have an irregular shape, less sister chromatid cohesion at 5S rDNA loci, and a reduced amount of centromeric histone CENH3. While the chromosomes of the embryo and endosperm nuclei are initially organized in Rabl configuration, the centromeres and telomeres are intermingled within the nuclear space in the endoreduplicated nuclei with an increasing endoreduplication level. Such a loss of chromosome organization suggests that Rabl configuration is introduced and further reinforced by mitotic divisions in barley cell nuclei in a tissue- and seed agedependent manner.
DOI: 10.1093/jxb/erad036
Fulltext: kontaktujte autory z ÚEB
Autoři z ÚEB: Martin Kovačik, Anna Nowicka, Aleš Pečinka, Mahmoud Said, Jana Zwyrtková