1 results
5 - Identification of miRNAs in the plant Oryza sativa
- from I - Discovery of microRNAs in various organisms
-
- By Hui Zhou, Biotechnology Research Center Key Laboratory of Gene Engineering of the Ministry of Education Zhongshan University Guangzhou, 510275 People's Republic of China, Yue-Qin Chen, Biotechnology Research Center Key Laboratory of Gene Engineering of the Ministry of Education Zhongshan University Guangzhou, 510275 People's Republic of China, Yu-Chun Luo, Biotechnology Research Center Key Laboratory of Gene Engineering of the Ministry of Education Zhongshan University Guangzhou, 510275 People's Republic of China, Jia-Fu Wang, Biotechnology Research Center Key Laboratory of Gene Engineering of the Ministry of Education Zhongshan University Guangzhou, 510275 People's Republic of China, Liang-Hu Qu, Biotechnology Research Center Key Laboratory of Gene Engineering of the Ministry of Education Zhongshan University Guangzhou, 510275 People's Republic of China
- Edited by Krishnarao Appasani
- Foreword by Sidney Altman, Victor R. Ambros
-
- Book:
- MicroRNAs
- Published online:
- 22 August 2009
- Print publication:
- 20 December 2007, pp 70-82
-
- Chapter
- Export citation
-
Summary
Introduction
MicroRNAs (miRNAs) are single-stranded small RNAs of c.22 nt in length that function as post-transcriptional negative regulators in plants and animals (Bartel, 2004; Kim, 2005). Among all the categories of endogenous small RNAs, these tiny RNAs have received the most notice (Sontheimer and Carthew, 2005). They act as small guides and direct negative regulations through sequence complementarity to the 3′-untranslated regions (UTRs) in animals or coding sequences in plants of an even larger number of target mRNAs (Grishok et al., 2001; Lai, 2002; Bartel and Bartel, 2003). Now miRNA genes are recognized as a pervasive and widespread feature of animal and plant genomes. A large number of miRNAs have been characterized from different animals such as the worm Caenorhabditis elegans, the fly Drosophila, and mammals including the human, the mouse and the rat. The total number of miRNAs in multicellular organisms was estimated to represent about 1% of all genes (Lim et al., 2003b; Grad et al., 2003; Bartel, 2004). However, recent studies show the number of miRNAs in the primate is larger than initially believed (Berezikov et al., 2005; Bentwich et al., 2005). Bioinformatic analysis implies that 25% of vertebrate genes are conserved targets of the miRNAs (Lewis et al., 2005). In total, multiple experimental and computational strategies all indicate that the true extent of miRNA regulation in complex organisms has not been fully recognized.