tailieunhanh - Báo cáo sinh học: "The THO complex as a key mRNP biogenesis factor in development and cell differentiation"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: The THO complex as a key mRNP biogenesis factor in development and cell differentiation. | Jimeno and Aguilera Journal of Biology 2010 9 6 http content 9 1 6 Journal of Biology MINIREVIEW L__ The THO complex as a key mRNP biogenesis factor in development and cell differentiation Sonia Jimeno and Andrés Aguilera See research article http 1741-7007 8 1 Abstract The THO complex is a key component in the eo-transeriptional formation of messenger ribonucleoparticles that are competent to be exported from the nucleus yet its precise function is unknown. A recent study in BMC Biology on the role of the THOC5 subunit in cell physiology and mouse development provides new clues to the role of the THO complex in cell differentiation. As soon as the pre-mRNA has been transcribed from DNA in the nucleus it is processed into a mature ribonucleoprotein mRNP particle which is competent to be exported from the nucleus. The THO complex a nuclear protein complex conserved from yeast to humans is involved in the biogenesis of mRNP particles and functions at the interface between transcription and RNA export Figure 1 . Although it is now clear that the THO complex has a role in RNA metabolism the initial studies that ended in the identification of this key complex had nothing to do with transcription mRNP biogenesis or RNA export. The first known component of THO Hpr1 was identified through a genetic screen for hyper-recombinant mutants in Saccharomyces cerevisiae. Subsequent genetic and molecular characterization of mutants in which the hprl gene had been deleted hprlA mutants linked the hprlA hyper-recombination phenotype to transcription and showed that Hpr1 was involved in transcriptional elongation. Tho2 was then identified as a high-copy-number suppressor of hprlA. Yeast tho2A mutants also showed a strong hyper-recombination phenotype that was linked to a transcription elongation defect reviewed in 1 . Correspondence aguilo@ Centro Andaluz de Biología Molecular y Medicina Regenerativa Av. Américo Vespucio s n 41092 Sevilla