The Molecular Biology of Meiosis in Plants

Abstract

Meiosis is the cell division that reshuffles genetic information between generations. Recently, much progress has been made in understanding this process; in particular, the identification and functional analysis of more than 80 plant genes involved in meiosis have dramatically deepened our knowledge of this peculiar cell division. In this review, we provide an overview of advancements in the understanding of all aspects of plant meiosis, including recombination, chromosome synapsis, cell cycle control, chromosome distribution, and the challenge of polyploidy.

High-Resolution Mapping of Crossover Events in the Hexaploid Wheat Genome Suggests a Universal Recombination Mechanism

“…In all eukaryotes studied so far, the distribution of COs is not homogeneous along the chromosomes (Lukaszewski and Curtis 1993;Tenaillon et al 2002;Saintenac et al 2009;Mayer et al 2012;Pan et al 2012;Choulet et al 2014;Choi and Henderson 2015;Mercier et al 2015). For cultivated crops, this implies a decrease of the breeding power in regions showing low CO rates (Rodgers-Melnick et al 2015).…”

“…KEYWORDS recombination; meiosis; bread wheat; linkage disequilibrium; transposon; hotspot; sequence motif M EIOTIC recombination is a process that allows reshuffling of diversity by the reciprocal exchange of DNA called a crossover (CO). This phenomenon is conserved in most eukaryotes (for a review see Mercier et al 2015) and follows the formation of a double-strand break (DSB) of DNA generated by the topoisomerase SPO11 complex. However, the number of DSBs is at least 10-to 50-fold greater than the number of COs which rarely exceeds three per bivalent chromosome per meiosis (Mercier et al 2015).…”

“…This phenomenon is conserved in most eukaryotes (for a review see Mercier et al 2015) and follows the formation of a double-strand break (DSB) of DNA generated by the topoisomerase SPO11 complex. However, the number of DSBs is at least 10-to 50-fold greater than the number of COs which rarely exceeds three per bivalent chromosome per meiosis (Mercier et al 2015).…”

“…This phenomenon is conserved in most eukaryotes (for a review see Mercier et al 2015) and follows the formation of a double-strand break (DSB) of DNA generated by the topoisomerase SPO11 complex. However, the number of DSBs is at least 10-to 50-fold greater than the number of COs which rarely exceeds three per bivalent chromosome per meiosis (Mercier et al 2015). This paucity of COs per meiosis with regards to the number of DSBs suggests the existence of a tight control and regulation of recombination in plants that promote DSB repair in a manner that does not lead to COs. For example, the study of the two helicases AtFANCM and RECQ4 (AtRECQ4A and AtRECQ4B) (Crismani et al 2012;Knoll et al 2012;Girard et al 2014;Séguéla-Arnaud et al 2015) revealed three-and sixfold CO frequency increases in the Atfancm single mutant and the Atrecq4a/Atrecq4b double mutant, respectively, compared to the wild type.…”

“…At least one CO per chromosome is absolutely required to ensure a correct segregation of chromosomes during meiosis (Mercier et al 2015). In all eukaryotes studied so far, the distribution of COs is not homogeneous along the chromosomes (Lukaszewski and Curtis 1993;Tenaillon et al 2002;Saintenac et al 2009;Mayer et al 2012;Pan et al 2012;Choulet et al 2014;Choi and Henderson 2015;Mercier et al 2015).…”