Evolutionary analyses of the miR827 family and its target genes in land plants

• Main Authors: Cuei-Huan Syu, 徐翠環
• Other Authors: Li-Ching Hsieh
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/95694469419663381111

碩士 === 國立中興大學 === 基因體暨生物資訊學研究所 === 105 === MicroRNAs (miRNAs) are endogenous small non-coding RNAs that are involved in the control of a variety of physiological and developmental processes in multicellular organisms by targeting mRNAs for cleavage or repressing translation. Phosphorus, one kind of macroelements, is essential to living organisms. In the processes of the phosphorous absorption and regulation, miRNAs also act as an important regulator. Previous studies showed that miR827 is highly expressed to suppress NLA (nitrogen limitation adaptation) under phosphate (Pi) starvation in Arabidopsis. However, the target gene of miR827 in Oriza is PHT5 (phosphate transporter 5). In order to know the cause of making such the difference between monocots’ and eudicots’ model species, we try to analyze the phylogeny and selection pressure of NLA and PHT5 between land plants. The results showed that miR827 candidate can be found in most angiosperm plants except legumes and the situation that the target of miR827 is NLA only appears in Brassicales. Both results may be caused by themselves whole genome duplication events which are common in plant kingdom and are always one of the reason of plant evolution. The data of selection pressure suggested that both NLA and PHT5 were under purifying selection, so we think the evolution pressure may not be the reason that cause the shift of miR827’s target gene in Brassicales. Our study reveals distribution of miR827 and the change in its target preference in plant kingdom.