Dissecting plant meiosis using Arabidopsis thaliana mutants.

Meiosis is a key stage in the life cycle of all sexually reproducing eukaryotes. In plants, specialized reproductive cells differentiate from somatic tissue. These cells then undergo a single round of DNA replication followed by two rounds of chromosome division to produce haploid cells that then undergo further rounds of mitotic division to produce the pollen grain and embryo sac. A detailed cytological description of meiosis has been built up over many years, based on studies in a wide range of plants. Until recently, comparable molecular studies have proved too challenging, however, a number of groups are beginning to use Arabidopsis thaliana to overcome this problem. A range of meiotic mutants affecting key stages in meiosis have been identified using a combination of screening for plants exhibiting reduced fertility and, more recently, using a reverse genetics approach. These are now providing the means to identify and characterize the activity of key meiotic genes in flowering plants.