title: [The impact of microRNAs on the evolution of metazoan complexity].
abstract: MicroRNAs (miRNAs) are a novel class of ~22 nt non-coding small RNAs. As crucial post-transcriptional regulators, miRNAs are involved in comprehensive biological processes such as developmental timing, cell proliferation and differentiation, oncogenesis and viral defenses. In addition to the roles in ontogenic physiology, researches on the area of miRNA phylogenetic conservation and diversity suggested that miRNAs play important roles in animal evolution through driving phenotypic variations in development. It has been postulated that miRNAs have enormous impacts on phenotypic variation and developmental complexity. Here we reviewed recent advances in the studies on the roles of miRNA in animal evolution, from aspects of the rate of miRNA evolution, the spatio-temporal expression pattern, the variation of target sites, and miRNA gene dynamics. We gave evidence to support the hypothesis that innovations in miRNA-mediated regulations drive the increase of metazoan complexity.
authors.affiliation: Key Laboratory of Molecular and Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China. dzh0128@genetics.ac.cn
authors.forename: Zhong-Hua
authors.initials: ZH
authors.lastname: Dai
authors.forename: Liang-Biao
authors.initials: LB
authors.lastname: Chen
mesh_terms: D000818:Animals; D056890:Eukaryota / Q000235:genetics* / Q000502:physiology; D019143:Evolution, Molecular; D006801:Humans; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism
chemical_list: D035683:MicroRNAs