Overexpressing drought-responsive miRNA 156 in rice (Oryza sativa L.) enhances drought stress resistance

Drought;OsmiR156;OsSPL;CRISPR/Cas9;narrow-leaf;631

국제농업기술대학원 국제농업기술학과 ;

University:서울대학교 대학원

关键词: Drought;    OsmiR156;    OsSPL;    CRISPR/Cas9;    narrow-leaf;    631;   

Others  :  http://s-space.snu.ac.kr/bitstream/10371/161114/1/000000157590.pdf

美国|英语

来源: Seoul National University Open Repository

【 摘 要 】

Globally the earth is facing an extreme climate changes including flood andhigh temperatures, changing the earth’s surface and weather rapidly. These rapidchanges cause a remarkable reduction in plant growth and productivity. Thediscovery of micro RNA in plant has open a new field of study in plantbiotechnology. MicroRNAs play a vital role in abiotic stress and cropimprovement by regulating target gene expression. MicroRNA156 (miR156) is ahighly conserved and emerging tool for improving various plant traits includingcrop productivity and drought stress tolerance. The aim of this study was toinvestigate how miR156 genes interacts with target genes and induce droughtstress tolerance. To analyze its role, we constructed overexpressing miR156 linesand knockout lines by using CRISPR/Cas9 system. The sequencing analysis,however, showed no mutation in mature microRNA sequence in both miR156dand miR156g Cas9-mediated mutation lines. As a result, we proceeded researchwith only overexpressing miR156d and miR156g lines. We observedoverexpressing miR156 plants had more tolerant to drought stress than nontransgenic with the higher survival rate and Fv/Fm value. Next, we predictedsome targets and screened genes showing antagonic expression pattern tomiR156d and miR156g by qRT-PCR. Our highest-ranking candidates includeSPL2, SPL17, SPL18, 01t0187200-01 and 09t0513100-01. Based on these results,it can be concluded that overexpressing miRNA156d and miR156g genesimprove rice drought tolerance by interacting with its target genes. Finally, it isimportant to study the interaction between miRNA156 and SPL during flowerinduction and seed development and needed to address their role in cell numberand size during early growth stages. This study provides a strong background forplant biotechnology and crop improvements and offer an important source forfurther functional analysis and molecular breeding for drought stress tolerance inrice.