Fellow and Tutor in Biological Sciences and IT Fellow, St Hilda's College
Dmitry Filatov joined the University of Oxford (Dept. of Plant Sciences) and St Hilda's College in 2007 after six years of teaching Biology and Genetics at the University of Birmingham. He lectures in the 2nd year Evolution and Quantitative Methods courses.
Population genetics and molecular evolution. My research interests are connected with experimental molecular population genetics and evolution. In particular, I am interested in evolution of sex chromosomes, mating systems, molecular adaptation and in speciation process. The experimental systems used in my laboratory range from plants to humans, with current main focus in plants. We use dioecious Silene latifolia to study sex chromosome evolution, population genetics of speciation and quantitative genetics of sexual dimorphism. We also use endemic Hawaiian plant genus Schiedea (Caryophyllaceae), that undergone recent ‘explosive’ adaptive radiation, to study molecular adaptation and population genetics of speciation. Recently we also started to study adaptation and speciation in Senecio and sex chromosome evolution in Silene smut fungus Microbotryum violaceum.
Research highlights: Recently we demonstrated that photosynthetic plant RbcL gene often evolves under positive selection (Kapralov & Filatov submitted). This was a very unexpected finding because this gene was regarded as very conservative housekeeping gene. As this gene is widely used by botanists for phylogenetic reconstructions, it may have wide implications for plant systematics. We discovered that rapid adaptive radiation in Hawaiian endemic plant genus Schiedea (Caryophyllaceae) was accompanied by strong adaptive selection at chloroplast photosynthetic enzyme Rubisco (Kapralov & Filatov 2006). Adaptive selection in this enzyme was most pronounced in Schiedea species that undergone significant habitat shifts (e.g. adaptation to semi-desert like conditions, or to wet shady rainforest), suggesting that it might have been involved in adaptations to diverse ecological conditions. This is one of the first examples of molecular adaptation during rapid adaptive radiation in plants. We reported unexpectedly strong population differentiation (Fst~0.9) for the Silene latifolia Y-linked genes (Ironside and Filatov 2005). This contrasted with little or no population differentiation for other parts of the genome, such as the X-linked or chloroplast genes (Muir and Filatov submitted). The finding of strong population differentiation in Silene Y-linked genes stimulated a new direction of research in several Silene laboratories to understand the causes of this phenomenon. Using comparative mapping analysis of Silene latifolia X chromosomes and homologous chromosomes in non-dioecious Silene vulgaris I demonstrated that recently evolved S. latifolia sex chromosomes have originated from a single pair of autosomes that stopped to recombine and diverged into the X and Y chromosomes (Filatov 2005 Genetics). In collaboration with Dr R. Moore (North Carolina State University, USA) and Prof. D. Charlesworth lab (University of Edinburgh, UK) we conducted physical mapping of the Y-linked genes in Silene latifolia and their homologs in non-dioecious S. vulgaris. Comparisons of these maps revealed that the order of the genes on the Y chromosome substantially differs from that on the X in S. latifolia and on the autosome in S. vulgaris, probably due to multiple inversions on the Y chromosome. These inversions could have played a role in cessation of recombination between the X- and Y-chromosomes in S. latifolia. (Bergero, Moore, Filatov and Charlesworth in preparation). I demonstrated that segregation analysis is probably the best method to search for new X- and Y-linked genes in plants (Filatov 2005 Meth. in Enzymol.) and using this method I isolated two new sex-linked genes from dioecious plant Silene latifolia (Filatov 2005 Mol. Biol. Evol.). Our work provided the first experimental support for the reduced DNA diversity on the plant Y chromosome (Filatov et al. 2000, 2001; Laporte et al 2005; Ironside and Filatov 2005). This supports theoretical predictions (e.g. Charlesworth & Charlesworth 2000) and helps to understand the evolutionary forces that shape sex chromosomes at the early stages of sex chromosome evolution. We demonstrated that different chromosomes in a plant genome might have significantly different mutation rates; in particular, Silene latifolia Y chromosome has significantly higher mutation rate than the X (Filatov and Charlesworth 2002). Contrary to common belief that mammalian Y-chromosomes are evolutionary deserts, we demonstrated that positive selection acts in at least two primate Y-linked genes, suggesting that adaptive Darwinian evolution may be common on mammalian Y-chromosomes (Gerrard and Filatov 2005). We demonstrated that genes in frequently recombining human pseudoautosomal region mutate faster than elsewhere in the genome, supporting the view that recombination might be mutagenic to some extent (Filatov and Gerrard 2003; Filatov 2004; Bussell et al 2006).
Ten most recent papers:
1. Muir & Filatov 2007 A selective sweep in the chloroplast DNA of dioecious Silene (section Elisanthe). Genetics. 177: 1239-1247 .
2. Kapralov M.V., and D.A.Filatov 2007 Widespread positive selection in the photosynthetic Rubisco enzyme. BMC Evol Biol.7:73.
3. Kapralov M.V. and D.A.Filatov 2006 Molecular adaptation during adaptive radiation in the Hawaiian endemic genus Schiedea. PLOS One, 1:e8.
4. Bussell J.J., N.M.Pearson, R.Kanda, D.A.Filatov and B.T.Lahn 2006 Human polymorphism and human-chimpanzee divergence in pseudoautosomal region correlate with local recombination rate. Gene, 368: 94-100.
5. Ironside J.E. and D.A. Filatov 2005 Extreme population structure and high interspecific divergence of the Silene Y-chromosome. Genetics, 171: 705-713.
6. Filatov D.A. 2005 Evolutionary history of Silene latifolia sex chromosomes revealed by genetic mapping of four genes. Genetics, 170: 975-979.
7. Filatov D.A. 2005 Substitution rates in a new Silene latifolia sex-linked gene, SlssX/Y. Mol. Biol. Evol., 22: 402-408.
8. Filatov D.A. 2005 Isolation of genes from plant Y-chromosomes. Methods in Enzymology, 395: 418-442.
9. Filatov D.A. 2005 Stickleback's view of sex chromosome evolution. Heredity 94: 275-276.
10. Gerrard D.T., and D.A. Filatov 2005 Positive and negative selection on mammalian Y chromosomes. Mol. Biol. Evol., 22: 1423-1432.
