W318 Identification and Characterization of miRNAs, Targets and Their Potential Regulatory Network in Fruit Crops

Date: Saturday, January 14, 2012
Time: 11:05 AM
Room: Pacific Salon 3
Rui Xia , Virginia Tech, Blacksburg, VA
Hong Zhu , USDA-ARS, Kearneysville, WV
Chris Dardick , USDA-ARS, Kearneysville, WV
Ann Callahan , USDA-ARS, Kearneysville, WV
Zongrang Liu , USDA-ARS, Kearneysville, WV
MicroRNAs (miRNAs) that are transcribed and processed as endogenous 21 - 22 nucleotide (nt) RNAs, have been shown to play an important role in the regulation of gene expression at post-transcriptional level in plants. However, their regulatory roles in fruit crops remain to be elucidated and even miRNA genes and their targets have not been fully investigated in major fruit crops. Recently, we took advantage of a deep sequencing approach, in combination with computation and molecular analyses, to identify both conserved and fruit-specific miRNAs in peach and apple, respectively.  Molecular analysis showed that the majority of these miRNAs including conserved and novel ones displayed differential expression among various tissues in both species. Using degradation analyses we were able to identify gene targets for more than 35% of miRNAs identified, and most of the identified miRNAs target to a single gene transcript while some of them can target up to 9 gene transcripts. Additionally, a multiple miRNAs-mediated and ensuing trans-acting siRNAs-cascaded regulatory network has also been delineated, and further characterization of this regulatory network should provide an insight into understanding miRNAs’ function in fruit crops at a global level.