The regulatory mechanisms controlling meiotic cross-over patterning in plants

Most sexually reproducing eukaryotes use a specialized cell division called meiosis to halve the complement of chromosomes in their gametes. During meiotic prophase I, homologous chromosomes (homologs) recombine by reciprocally exchanging DNA to form cross-overs (COs) that are required for accurate chromosome segregation. COs also reshuffle parental genomes to create genetic diversity among progeny. Molecular genetic studies have identified hundreds of genes involved in meiotic recombination, which have been well summarized in several reviews. Here, we highlight recent advances in understanding endogenous mechanisms that regulate the frequency and distribution of meiotic COs, also called CO patterning. Specifically, we focus on genome-wide regulation, epigenetic control, transcription regulation, and post-transcription processes. Additionally, we highlight open questions that still need further investigation in this field.