The genetic basis of sex determination in moss
The sex determining regions (SDRs) of chromosomes have been studied in most organisms that have two sets of chromosomes and are therefore diploid. Relatively little is known, however, about haploid organisms with one set of chromosomes such as the fire moss. The EU-funded CERATOSEX (Identification and characterisation of the sex locus in the dioecious moss Ceratodon purpureus) project has studied the genome of this plant that can live practically anywhere on earth. The researchers then aligned the transcriptome or products of the genes with the genetic structure. Marrying up the gene products with their respective gene(s) will substantially increase the accuracy of determining what each gene is responsible for, including their functions. For future research, the team plan to compare the fire moss genome with three close relatives, Sphagnum fallax, Ceratodon purpureus and Physcomitrella patens. Building on project research results, the genes can be organised into blocks of linked genes and then into pseudochromosomes. Most importantly, the researchers expect to be able to identify genes differentially expressed between male and female plants and genes present in one sex but absent in the other. Data from the CERATOSEX project will form a substantial knowledge base for further research into sexual differentiation in organisms that have a haploid-dominant life cycle.
Keywords
Sex determination, fire moss, haploid, genome, transcriptome, pseudochromosome
