Identification of miRNAs involved in flowering pathway in sugar beet (Beta vulgaris L.)

Document Type : Scientific - Research


1 Ph.D. in Biotechnology, Agriculture Faculty, Bu-Ali Sina University, Hamedan, Iran.

2 Associate Professor of Agriculture Faculty, Bu-Ali Sina University, Hamedan, Iran.

3 Assistant Professor of Payamenoor University, Hamadan, Iran.


Transition from vegetative to reproductive stage is one of the important procedures in most crops such as sugar beet which is regulated by the complex network of proteins. So far, several regulatory pathways involved in flowering and bolting and related genes have been identified in the Arabidopsis as a model plant. Age-related pathway is one of the important pathways involved in transition from vegetative to reproductive stage that is influenced by miR156 and miR172. In order to identify the sequence of the above mentioned genes in sugar beet genome, their sequences were collected from several plants and were aligned with sugar beet Refseq-genomic sequence. Regions with a common sequence were identified and evaluated in detail. For miR156 coding gene, only 127 bp in chromosome 2, and for miR172 coding gene only 110 bp in chromosome 9 had the full-length of miR precursor sequence in the sugar beet genome. In order to isolate the miR156 coding gene from the sugar beet genome, specific primers were designed. The miR156 coding gene was amplified from genomic DNA of sugar beet by polymerase chain reaction technique using specific primers of MIRF and MIRR. As expected, the 127 bp gene was amplified and showed 99% similarity with the sequence of the miR156. Identifying and studying these effective genes in the flowering process will open the way for the ability to verify their exact performance in sugar beet flowering and bolting processes.


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