在細胞發(fā)育過程中,，調控細胞從前體細胞進化到成熟細胞的遺傳因素是什么,？三項大型研究在日前在線出版的《自然·遺傳學》期刊上報告說,，他們揭開了這個秘密。
不成熟細胞是指仍需要發(fā)育的細胞，而成熟細胞則是指已擁有特別功能的細胞。器官或組織的完整發(fā)育取決于不成熟細胞和成熟細胞之間的兼容性,。迄今為止，科學家們對這種細胞在生長與特別功能之間的切換是如何進行的仍知之甚少,。
Yoshihide Hayashizaki,、John Mattick和Piero Carninci領導的三個獨立研究小組，利用深度測序技術評估了細胞發(fā)育過程中的基因表達的泛基因組變化,。Carninci小組發(fā)現了重復移動因子的泛基因組表達,，他們鑒別出25萬個以前未知的基因表達始點，以及這些重復因子在鄰近基因全表達中的功能后果,；Mattick小組得出了另外一個有趣的發(fā)現：他們鑒別出一種全新的進化保守片段RNAs,，它們位于活躍基因的始點位置。這兩項發(fā)現與Hayashizaki小組的工作結合起來,，有助于全面理解細胞發(fā)育的動態(tài)控制過程,，這個控制過程支持了不成熟生長細胞向成熟功能細胞的轉化。（生物谷Bioon.com）
生物谷推薦原始出處：
Nature Genetics 41, 859 (2009)doi:10.1038/ng0709-859a
Tiny RNAs associated with transcription start sites in animals
Ryan J Taft, Evgeny A Glazov, Nicole Cloonan, Cas Simons, Stuart Stephen, Geoffrey J Faulkner, Timo Lassmann, Alistair R R Forrest, Sean M Grimmond, Kate Schroder, Katharine Irvine, Takahiro Arakawa, Mari Nakamura, Atsutaka Kubosaki, Kengo Hayashida, Chika Kawazu, Mitsuyoshi Murata, Hiromi Nishiyori, Shiro Fukuda, Jun Kawai, Carsten O Daub, David A Hume, Harukazu Suzuki, Valerio Orlando, Piero Carninci, Yoshihide Hayashizaki & John S Mattick
It has been reported that relatively short RNAs of heterogeneous sizes are derived from sequences near the promoters of eukaryotic genes. As part of the FANTOM4 project, we have identified tiny RNAs with a modal length of 18 nt that map within -60 to +120 nt of transcription start sites (TSSs) in human, chicken and Drosophila. These transcription initiation RNAs (tiRNAs) are derived from sequences on the same strand as the TSS and are preferentially associated with G+C-rich promoters. The 5' ends of tiRNAs show peak density 10–30 nt downstream of TSSs, indicating that they are processed. tiRNAs are generally, although not exclusively, associated with highly expressed transcripts and sites of RNA polymerase II binding. We suggest that tiRNAs may be a general feature of transcription in metazoa and possibly all eukaryotes.
1 Institute for Molecular Bioscience, The University of Queensland, St. Lucia, Australia.
2 Diamantina Institute for Cancer, Immunology and Metabolic Medicine, The University of Queensland, Princess Alexandra Hospital, Woolloongabba, Australia.
3 RIKEN Omics Science Center, RIKEN Yokohama Institute, Yokohama, Kanagawa, Japan.
4 The Eskitis Institute for Cell and Molecular Therapies, Griffith University, Nathan, Australia.
5 The Roslin Institute and Royal (Dick) School of Veterinary Studies, The University of Edinburgh, Roslin, UK.
6 Dulbecco Telethon Institute, IRCCS Santa Lucia at EBRI, Rome, Italy.
7 Dulbecco Telethon Institute, IGB CNR, Naples, Italy.
8 The FANTOM Consortium.
9 RIKEN Omics Science Center.
10 General organizers (of the small RNA group).
