microRNA(miRNAs)是一类非编码小分子RNA,在植物生长发育、新陈代谢以及逆境生理中起重要作用.基于生物信息学的基因搜索和同源搜索,从NCBI数据库中登录的核果类果树的EST和GSS中寻找miRNAs.从核果类果树的107 982条ESTs和48 273条GSSs中搜寻到了11条miRNAs前体序列,编码11条成熟体序列,并预测到19个靶基因,分别编码与生长发育、新陈代谢和转录调节等相关的蛋白.利用miRbase数据库进一步分析表明:11条miRNAs属于8个microRNA家族,分别来自桃和梅,其大小为20 ～ 23 bp,其中6条为21 bp,而且ppe-miR162a和ppe-miR164f保守性最高.采用poly (A) RT-PCR方法随机对预测的ppe-miR156h,pmu-miR482,ppe-miR399a,ppe-miR171a进行组织表达验证,发现ppe-miR156h在果梅花芽中表达,pmu-miR482,ppe-miR399a,ppe-miR171a在桃叶片中表达.%MicroRNAs (miRNAs) are one kind of small RNAs that do not encode any proteins, however play critical role in developmental processes, metabolism and stress responses in plant. Here we present a study of bioinformatics prediction of miRNAs in Prunus using bioinformatics-based gene search based on blasting ESTs and GSSs in NCBI. Eleven precursors coding 11 mature miRNAs were found from 107 982 ESTs and 48 273 GSSs of Prunus, and 19 target genes, which encode proteins involved in developmental processes, metabolism and transcriptional regulation, were predicted. Further analysis of the miRbase database showed that 11 miRNAs belonged to 8 miRNA families from Prunus persica and Prunus mume, and were from 20 to 23 bp in length with 6 miRNAs being 21 bp in length. The miRNAs of ppe-miR162a and ppe-miR164f were the most conservative. In order to prove accuracy of the prediction, ppe-miR156h, pmu-miR482, ppe-miR399a, ppe-miR171 were identified by RT-PCR. The results showed that ppe-miR156h was expressed in flower buds of Prunus mume, and pmu-miR482, ppe-miR399a, and ppe-miR171a were expressed in leaves of Prunus persica.
展开▼
