Dr Catherine Merrick

My group studies the human malaria parasite Plasmodium falciparum. Research interests are centred around DNA biology, particularly the molecular mechanisms underlying DNA replication and cell cycle control in Plasmodium, which replicates by an unusual method called schizogony. I am also interested in mechanisms for silencing and promoting the recombination of a family of key virulence genes called var genes - particularly the role that G-quadruplex DNA structures may play in var gene control. Var genes encode the major parasite antigen expressed on infected red blood cells; they are found primarily at sub-telomeric loci and their variant expression is under epigenetic control. In fact, we have discovered that G-quadruplexes and their helicases have more general roles in genome stability/evolution in the malaria parasite as well. Finally, I have a long-standing interest in a group of NAD+-dependent deacetylase enzymes called sirtuins which regulate subtelomeric chromatin and virulence gene expression. My postdoctoral work linked the Plasmodium falciparum sirtuins to particular patterns of var gene expression and to severe malaria in human patients.