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: Short RNA half-lives in the slow-growing marine cyanobacterium Prochlorococcus. | Steglich et al. Genome Biology 2010 11 R54 http 2010 11 5 R54 w Genome Biology RESEARCH _ Open Access Short RNA half-lives in the slow-growing marine cyanobacterium Prochlorococcus Claudia Steglich 1 2 Debbie Lindell1 3 Matthias Futschik4 5 Trent Rector5 7 Robert Steen6 and Sallie W Chisholm 1 Abstract Background RNA turnover plays an important role in the gene regulation of microorganisms and influences their speed of acclimation to environmental changes. We investigated whole-genome RNA stability of Prochlorococcus a relatively slow-growing marine cyanobacterium doubling approximately once a day which is extremely abundant in the oceans. Results Using a combination of microarrays quantitative RT-PCR and a new fitting method for determining RNA decay rates we found a median half-life of minutes and a median decay rate of minutes for expressed genes - twofold faster than that reported for any organism. The shortest transcript half-life 33 seconds was for a gene of unknown function while some of the longest approximately 18 minutes were for genes with high transcript levels. Genes organized in operons displayed intriguing mRNA decay patterns such as increased stability and delayed onset of decay with greater distance from the transcriptional start site. The same phenomenon was observed on a single probe resolution for genes greater than 2 kb. Conclusions We hypothesize that the fast turnover relative to the slow generation time in Prochlorococcus may enable a swift response to environmental changes through rapid recycling of nucleotides which could be advantageous in nutrient poor oceans. Our growing understanding of RNA half-lives will help us interpret the growing bank of metatranscriptomic studies of wild populations of Prochlorococcus. The surprisingly complex decay patterns of large transcripts reported here and the method developed to describe them will open new avenues for the investigation and understanding of RNA decay for all .
