In Favor of Establishment: Regulation of Chromatid Cohesion in Plants

Abstract

In eukaryotic organisms, the correct regulation of sister chromatid cohesion, whereby sister chromatids are paired and held together, is essential for accurate segregation of the sister chromatids and homologous chromosomes into daughter cells during mitosis and meiosis, respectively. Sister chromatid cohesion requires a cohesin complex comprised of structural maintenance of chromosome adenosine triphosphatases and accessory proteins that regulate the association of the complex with chromosomes or that are involved in the establishment or release of cohesion. The cohesin complex also plays important roles in the repair of DNA double-strand breaks, regulation of gene expression and chromosome condensation. In this review, we summarize progress in understanding cohesion dynamics in plants, with the aim of uncovering differences at specific stages. We also highlight dissimilarities between plants and other eukaryotes with respect to the key players involved in the achievement of cohesion, pointing out areas that require further study.

Maize Dek15 Encodes the Cohesin-Loading Complex Subunit SCC4 and Is Essential for Chromosome Segregation and Kernel Development

“…Many genes involved in sister chromatid cohesion also play a role in developmental regulation (Nasmyth and Haering, 2009;Sebastian et al, 2009;Bolaños-Villegas et al, 2017). The dek15 and dek15-cas9 mutant alleles had small but variably sized kernels, with structurally deficient embryos and a reduced endosperm (Figures 1 and 4).…”

“…The manipulation of cohesin has potential applications in plant breeding, such as the production of clonal seeds using apomixis (Bolaños-Villegas et al, 2017). In two recent reports, genes associated with meiosis were knocked out using CRISPR/Cas9 to produce of clonal seeds in rice (Khanday et al, 2019;Wang et al, 2019).…”

“…Together, these proteins form a tetramer ring encircling chromatin (Haering et al, 2002;Gligoris et al, 2014). The cohesin complex proteins are highly conserved in microbes, plants, and animals (Nasmyth and Haering, 2009;Uhlmann, 2016;Bolaños-Villegas et al, 2017).…”

The Arabidopsis anaphase‐promoting complex/cyclosome subunit 8 is required for male meiosis

“…Meiosis I results in segregation of homologous chromosomes and meiosis II separates the sister chromatids. Several mechanisms ensure accurate segregation of chromosomes during meiosis, including the stepwise removal of cohesion from sister chromatid arms and centromeres (Rankin & Dawson, 2016;Bolanos-Villegas et al, 2017). However, the mechanisms that regulate the attachment of spindle microtubules to kinetochores to ensure proper chromosome alignment and the onset of anaphase (Di Fiore et al, 2016;Ji et al, 2018) are not as well understood, particularly in plants including Arabidopsis.…”

The Effect of Chromosome Structure upon Meiotic Homologous and Homoeologous Recombinations in Triticeae

“…The occurrence of a CO between homologous chromatids happens in a context in which each member of the partner and its sister chromatid are held together by a number of ring-shaped cohesin complexes scattered along the chromosomes axes and formed after DNA replication. The cohesin complexes also play an additional role in the DSBs repairing process [103]. Cohesion is released from chromosome arms at anaphase I, but not from the centromere region, where sister kinetochores remain associated and oriented to the same pole [104].…”