Centromere diversity and its evolutionary impacts on plant karyotypes and plant reproduction.

Karyotype changes are a formidable evolutionary force by directly impacting cross-incompatibility, gene dosage, genetic linkage, chromosome segregation, and meiotic recombination landscape. These changes often arise spontaneously and are commonly detected within plant lineages, even between closely related accessions. One element that can influence drastic karyotype changes after only one (or few) plant generations is the alteration of the centromere position, number, distribution, or even its strength.

The meiotic topoisomerase VI B subunit (MTOPVIB) is essential for meiotic DNA double-strand break formation in barley (Hordeum vulgare L.).

In barley (Hordeum vulgare), MTOPVIB is critical for meiotic DSB and accompanied SC and CO formation while dispensable for meiotic bipolar spindle formation. Homologous recombination during meiosis assures genetic variation in offspring. Programmed meiotic DNA double-strand breaks (DSBs) are repaired as crossover (CO) or non-crossover (NCO) during meiotic recombination.

The impact of Polycomb group (PcG) and Trithorax group (TrxG) epigenetic factors in plant plasticity.

Current advances indicate that epigenetic mechanisms play important roles in the regulatory networks involved in plant developmental responses to environmental conditions. Hence, understanding the role of such components becomes crucial to understanding the mechanisms underlying the plasticity and variability of plant traits, and thus the ecology and evolution of plant development. We now know that important components of phenotypic variation may result from heritable and reversible epigenetic mechanisms without genetic alterations.