Role of miR156 and miR171 in Drought Response of Tobacco
Bioengineering and Biological Sciences, MSc. Thesis, 2015
Prof. Dr. Hikmet Budak (Thesis Advisor), Prof. Ersin Göğüş,
Assoc. Prof. Bahar Soğutmaz Özdemir
Date &Time: 30th of June, 2015 – 13:30
Place: FENS L067
Keywords: microRNA, Nicotiana, overexpression, drought
microRNAs (miRNAs) are genetic regulator RNA molecules belonging to small RNA family. Functions of miRNAs in plants range in a broad spectrum, one of which is the drought stress that is a major environmental stress factor globally affecting plant growth and development. Overexpression of a gene indicates elevated expression of a certain gene beyond its normal expression level. Studies seeking for function of plant miRNAs in response to overexpression carries significant role for agricultural improvement. Among wide variety of plant microRNAs with diverse functions, miR156 and miR171 have critical roles on plant development and stress tolerance. In the first part of our study, different Turkish tobacco cultivars were subjected to drought stress and RNA from leaf tissue of these plants was utilized for changes of gene expression levels in miR156 and miR171. In the second part of project, leaf explants of grown tobacco cultivars were transformed with Agrobacterium tumefaciens containing MIR156 and MIR171 genes of tobacco cultivars and successful overexpressed transgenic plants were selected. Callus tissue formed from transgenic and control leaf explants groups were also subjected to drought stress and drought stress response of miR156 and miR171 expression levels were analyzed by quantitative real time PCR. Scope of this study could be utilized for a better understating of molecular mechanisms of drought stress and the roles of miRNAs.