1. Department of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Vorbyevy Gory 1-73, Moscow 119992, Russia
2. Sector for Molecular Evolution, Institute for Information Transmission Problems of the Russian Academy of Sciences (Kharkevich Institute), Bolshoi Karetny pereulok 19, Moscow 127994, Russia
3. Life Sciences Institute and Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109-2216, USA