Speaker: Begum Serra Buyuktarakci
Affiliation: Uppsala University

Abstract:
Sexual reproduction is widespread among eukaryotes however it is not very wellknown
outside of the animals, land plants and fungi kingdoms. Metamonada, a phylum of
single-celled eukaryotes, comprises diverse lineages including diplomonads. Some members of diplomonads have been assumed to be asexual, though the presence of putative meiotic genes were reported in recent studies. I applied a comparative phylogenomic approach to clarify the occurrence of sexual life cycle in diplomonads. Here, I surveyed the sets of sex-related genes in the ongoing Hexamita inflata genome project. The inventory of sex-related genes was compiled based on the major sexual processes: cell fusion (plasmogamy), nuclear fusion (karyogamy) and meiosis. My analysis showed that H. inflata encodes karyogamy protein, Gex1 but not the plasmogamy protein, Hap2. Putatively meiosis specific genes: Spo11, Dmc1, Hop2 and Mnd1 were identified in H. inflata genome. Based on my findings, H. inflata possesses Mer3/Hfm1 gene which is required during meiotic crossover formation and postmeiotic
genes (Mlh2/Pms1 and Mad2). I hypothesize that H. inflata is capable of some sex-related processes such as nuclear fusion and meiotic inter-homolog recombination. My results indicate that the sex machinery varies among diplomonads and other Metamonada based on the wide distribution of sex-related genes.