Department of Agronomy, Zhejiang University, Hangzhou, China.
BMC Evol Biol. 2010 Apr 30;10:119. doi: 10.1186/1471-2148-10-119.
Endogenous non-coding small RNAs (21-24 nt) play an important role in post-transcriptional gene regulation in plants. Domestication selection is the most important evolutionary force in shaping crop genomes. The extent of polymorphism at small RNA loci in domesticated rice and whether small RNA loci are targets of domestication selection have not yet been determined.
A polymorphism survey of 94 small RNA loci (88 MIRNAs, four TAS3 loci and two miRNA-like long hairpins) was conducted in domesticated rice, generating 2 Mb of sequence data. Many mutations (substitution or insertion/deletion) were observed at small RNA loci in domesticated rice, e.g. 12 mutation sites were observed in the mature miRNA sequences of 11 MIRNAs (12.5% of the investigated MIRNAs). Several small RNA loci showed significant signals for positive selection and/or potential domestication selection.
Sequence variation at miRNAs and other small RNAs is higher than expected in domesticated rice. Like protein-coding genes, non-coding small RNA loci could be targets of domestication selection and play an important role in rice domestication and improvement.
内源性非编码小 RNA（21-24 个核苷酸）在植物的转录后基因调控中发挥重要作用。驯化选择是塑造作物基因组的最重要进化力量。驯化水稻中小 RNA 位点的多态性程度以及小 RNA 位点是否是驯化选择的目标尚未确定。
对驯化水稻中的 94 个小 RNA 位点（88 个 MIRNAs、4 个 TAS3 位点和 2 个 miRNA 样发夹）进行了多态性调查，生成了 2 Mb 的序列数据。在驯化水稻的小 RNA 位点观察到许多突变（替换或插入/缺失），例如在 11 个 MIRNAs 的成熟 miRNA 序列中观察到 12 个突变位点（被调查的 MIRNAs 的 12.5%）。几个小 RNA 位点显示出阳性选择和/或潜在驯化选择的显著信号。
驯化水稻中小 RNA 和其他小 RNA 的序列变异高于预期。与蛋白质编码基因一样，非编码小 RNA 位点可能是驯化选择的目标，并在水稻驯化和改良中发挥重要作用。
