Abstract: microRNA (miRNA) is a small RNA molecule of about 21 nt that can affect the physiological and biochemical functions of various plants. CRISPR/Cas9 is a well-developed system for edting target DNA sequences and has been successfully applied in many plants. miR171a is a kind of conserved miRNA family, which is involved in the regulation of plant growth and development and stress under stress. In this study, CRISPR/Cas9 technique was used to identify the functions of miR171a in Arabidopsis thaliana. The results showed that the expression of miR171a decreased in gene edited Arabidopsis lines. The expression of target gene SCL22 was up regulated. The increase of proline content in Arabidopsis lines was smaller than that of wild type after drought stress. The chlorophyll content, plant height and growth potential of gene edited Arabidopsis lines decreased. Drought stress results showed that inhibition of miR171 weakened the drought resistance of Arabidopsis lines. These results showed that CRISPR technology was effective in identifying the functions of miRNA.

Key words: CRISPR, STTM, miR171a, drought stress

摘要： miRNA是一段长约21 nt的RNA小分子,能够影响多种植物生理生化功能。CRISPR/Cas9是近年发展的可以靶向编辑DNA序列的技术，已广泛应用于多种植物。miR171a是一类保守的miRNA家族，参与对植物生长发育和逆境胁迫的调控。利用CRISPR/Cas9技术鉴定拟南芥miR171a的功能，结果表明基因编辑拟南芥株系中的miR171a表达量降低，靶基因SCL22表达量上调。干旱处理后基因编辑拟南芥株系中的脯氨酸含量上升幅度小于野生型。基因编辑拟南芥株系的叶绿素含量有不同程度的降低，株高和生长势增强。干旱胁迫结果显示对miR171的抑制使得拟南芥抗旱能力减弱，表明利用CRISPR技术鉴定miRNA的功能是有效的。

关键词: CRISPR, STTM, miR171a, 干旱胁迫