The molecular characterization and function of miRNAs on mediation of target gene silencing in plants

Abstract

MiRNAs belong to one type of noncoding RNAs involved in developmental regulation, genome maintenance, and defense in eukaryotes. In plants, the miRNAs are involved in many molecular interactions, including interfere with expression of mRNAs encoding factors that control developmental processes, stem cell maintenances, auxin responses, and other developmental and physiologic processes. In this paper, the molecular characterization and the functions of miRNAs on mediation of target gene silencing in plants have been overviewed. Further studies on the miRNAs will be helpful for elucidation of the molecular mechanism of post- transcriptional gene silencing in plants.

Key words： miRNAs; molecular characterization; RNA-induced silencing complex (RISC); target gene

Acknowledgements

This work was supported by the National Transgenic Major Program of China (No. 2009ZX08009-011B), the National Basic Research Program of China (973 Program) in the early stage (No. 2007CB116209), and the Foundation of Crop Growth Regulation Laboratory of Hebei Province, China.

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