He Xiang-Feng, Fang Yuan-Yuan, Feng Lei, Guo Hui-Shan
State Key Laboratory of Plant Genomics and National Center for Plant Gene Research (Beijing), Institute of Microbiology, Chinese Academy of Sciences, 100101 Beijing, China.
FEBS Lett. 2008 Jul 9;582(16):2445-52. doi: 10.1016/j.febslet.2008.06.011. Epub 2008 Jun 17.
Nine conserved miRNA families and three potential novel miRNAs in Brassica rapa were identified from a small RNA library. The expression patterns of some conserved miRNAs had different tissue specificity in Brassica and Arabidopsis. One of the three potential miRNAs, named bra-miR1885, was verified as a true functional miRNA. It could be induced specifically by Turnip mosaic virus (TuMV) infection, and target TIR-NBS-LRR class disease-resistant transcripts for cleavage. Based on the hypothesis for de novo generation of new miRNA genes and the sequence similarity between bra-MIR1885 precursor loci and target transcript sequences, we suggest that bra-MIR1885 is a new miRNA gene that originated through inverted duplication events from TIR-NBS-LRR class disease-resistant protein-coding gene sequences, which became bra-miR1885 targets.
从小RNA文库中鉴定出了白菜中的9个保守miRNA家族和3个潜在的新miRNA。一些保守miRNA的表达模式在白菜和拟南芥中具有不同的组织特异性。这3个潜在miRNA之一，命名为bra-miR1885，被证实是一个真正具有功能的miRNA。它可以被芜菁花叶病毒（TuMV）感染特异性诱导，并切割TIR-NBS-LRR类抗病转录本。基于新miRNA基因从头产生的假说以及bra-MIR1885前体基因座与靶转录本序列之间的序列相似性，我们认为bra-MIR1885是一个新的miRNA基因，它起源于TIR-NBS-LRR类抗病蛋白编码基因序列的反向重复事件，而这些序列成为了bra-miR1885的靶标。
