tailieunhanh - Báo cáo y học: " Strong functional patterns in the evolution of eukaryotic genomes revealed by the reconstruction of ancestral protein domain repertoi"

Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Wertheim cung cấp cho các bạn kiến thức về ngành y đề tài: Strong functional patterns in the evolution of eukaryotic genomes revealed by the reconstruction of ancestral protein domain repertoires. | Zmasek and Godzik Genome Biology 2011 12 R4 http 2011 12 1 R4 Genome Biology RESEARCH Open Access Strong functional patterns in the evolution of eukaryotic genomes revealed by the reeonstruetion of ancestral protein domain repertoires Christian M Zmasek Adam Godzik Abstract Background Genome size and complexity as measured by the number of genes or protein domains is remarkably similar in most extant eukaryotes and generally exhibits no correlation with their morphological complexity. Underlying trends in the evolution of the functional content and capabilities of different eukaryotic genomes might be hidden by simultaneous gains and losses of genes. Results We reconstructed the domain repertoires of putative ancestral species at major divergence points including the last eukaryotic common ancestor LECA . We show that surprisingly during eukaryotic evolution domain losses in general outnumber domain gains. Only at the base of the animal and the vertebrate sub-trees do domain gains outnumber domain losses. The observed gain loss balance has a distinct functional bias most strikingly seen during animal evolution where most of the gains represent domains involved in regulation and most of the losses represent domains with metabolic functions. This trend is so consistent that clustering of genomes according to their functional profiles results in an organization similar to the tree of life. Furthermore our results indicate that metabolic functions lost during animal evolution are likely being replaced by the metabolic capabilities of symbiotic organisms such as gut microbes. Conclusions While protein domain gains and losses are common throughout eukaryote evolution losses oftentimes outweigh gains and lead to significant differences in functional profiles. Results presented here provide additional arguments for a complex last eukaryotic common ancestor but also show a general trend of losses in metabolic capabilities and gain in regulatory complexity