Faller Michael, Guo Feng
Department of Biological Chemistry, David Geffen School of Medicine, Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA.
Biochim Biophys Acta. 2008 Nov;1779(11):663-7. doi: 10.1016/j.bbagrm.2008.08.005. Epub 2008 Aug 20.
microRNAs (miRNAs) are extensively involved in developmental programming. Some miRNAs are highly conserved, while others are lineage specific. All miRNAs maturate through a series of processing steps. Here we review recent progresses in the studies of early steps in miRNA biogenesis, focusing on animal systems. The miRNA maturation pathways are surprisingly diverse, involving transcription by RNA polymerase II or III, cleavage by the Drosha nuclease or the spliceosome, and sometimes modifications by the adenosine deaminase ADAR. The relationship between the diversity in miRNA biogenesis and the apparently rapid evolution of miRNA genes and functions is discussed.
微小RNA（miRNA）广泛参与发育编程。一些miRNA高度保守，而另一些则具有谱系特异性。所有miRNA都通过一系列加工步骤成熟。在此，我们综述了miRNA生物合成早期步骤研究的最新进展，重点关注动物系统。miRNA成熟途径惊人地多样，涉及RNA聚合酶II或III的转录、Drosha核酸酶或剪接体的切割，有时还涉及腺苷脱氨酶ADAR的修饰。我们还讨论了miRNA生物合成多样性与miRNA基因及功能明显快速进化之间的关系。
