Epigenetic control of meiotic recombination in plants

Abstract

Meiotic recombination is a deeply conserved process within eukaryotes that has a profound effect on patterns of natural genetic variation. During meiosis homologous chromosomes pair and undergo DNA double strand breaks generated by the Spo11 endonuclease. These breaks can be repaired as crossovers that result in reciprocal exchange between chromosomes. The frequency of recombination along chromosomes is highly variable, for example, crossovers are rarely observed in heterochromatin and the centromeric regions. Recent work in plants has shown that crossover hotspots occur in gene promoters and are associated with specific chromatin modifications, including H2A.Z. Meiotic chromosomes are also organized in loop-base arrays connected to an underlying chromosome axis, which likely interacts with chromatin to organize patterns of recombination. Therefore, epigenetic information exerts a major influence on patterns of meiotic recombination along chromosomes, genetic variation within populations and evolution of plant genomes. meiosis, recombination, epigenetic, crossover, chromatin Citation:Yelina N, Diaz P, Lambing C, Henderson IR.

Genetic differentiation and intrinsic genomic features explain variation in recombination hotspots among cocoa tree populations

“…A potential hypothesis that could explain the rapid 558 turnover of hotspots of recombination and the relative differences in recombination among 559 populations is that epigenetic changes are involved in controlling the turnover of recombination 560 in plants. This hypothesis is not unreasonable given the recent observation of epigenetic control 561 of recombination in plants (Yelina et al 2015). Further theoretical and simulation work should be 562 done in order to better understand the implications of the rapidly changing recombination 563 hotspots in adaptive dynamics.…”

Genome-wide transcription during early wheat meiosis is independent of synapsis, ploidy level and thePh1locus

“…Numerous post-translational modifications (PTMs) are known to take place during meiosis. Those involved in histone modifications (Sasaki et al, 2008; Xu et al, 2009; Kota et al, 2010; Greer et al, 2011; Yelina et al, 2014; Székvölyi et al, 2015; Termolino et al, 2016) are frequently associated with changes in transcription, which is one of the reasons why we expected to detect larger changes in the meiotic transcription profile. However, several PTM are also involved in the modification of other meiotic proteins (Watanabe et al, 1997; Carballo et al, 2008; Fukuda et al, 2012; Sato-Carlton et al, 2017).…”

“…A second possible explanation is that meiosis is mostly regulated at the post-transcriptional and post-translational level. There are several examples of post-transcriptional regulation during meiosis (Yelina et al, 2015 and references therein; Termolino et al, 2016 and references therein). Gene expression can be controlled at the RNA level, both quantitatively and qualitatively, and at various steps during RNA processing (alternative splicing, RNA editing, RNA silencing and translation regulation among others), with important consequences for the availability of different kinds of transcripts, and ultimately of proteins.…”

Transposable elements play an important role during cotton genome evolution and fiber cell development

“…TEs may cause transcriptional gene silencing (TGS) by methylating DNA (McCue et al, 2012) or histone, or impose post-transcriptional gene silencing (PTGS) by DNA cleavage or translational repression. But small RNA (miRNA or siRNA) might be the common actor in these different mechanisms based on recent experimental data Yelina et al, 2015;He et al, 2015).…”