Won-Bo Wang and Wei-Bin Hsu
Poster Presentations: J Antivir Antiretrovir
MicroRNAs (miRNAs) are the endogenous small non coding RNA (~21 nt), which play an important role to regulate gene expression in growth development and defense mechanism systems. Although a number of orchid species are always susceptible to Cymbidium mosaic virus (CymMV) infection, there is still no data available for CymMV defense mechanism in orchids regarding to miRNAs. To get insight into miRNAs profile of Ascocenda orchid infected with CymMV, two miRNA libraries were constructed from non-infected (AscoF) and CymMV infected (AscoV) Ascocenda and were generated by high through-put sequencing. With the availability of Illumina sequencer, a total of 8,811,192 clean reads consisting of 4,325,140 unique sequences ranging in size between 18-30 nt were provided from AscoF and AscoV libraries. After bioinformatics prediction and molecular analysis of Ascocenda miRNA libraries, twenty three conserved miRNA families and one precursor secondary structure were discovered. Moreover, miRNA target identification and classification showed 100 candidate target transcripts belong to several gene families with diverse biological functions. Obviously, the AscoF and AscoV presented different pattern of miRNA expression which related to growth development and defense mechanism systems in particular miR156, miR162, miR164, miR172, miR528 and miR529. In this report, we have identified by first time the conserved miRNAs presenting in Ascocenda orchid comparing with published Arabidopsis and rice miRNA libraries. Understanding from these experiments will useful to provide the growing database of orchid miRNAs, which can be the tool to generate genetic improvement of viral infection tolerance.
Udomporn PETCHTHAI obtained her Bachelor?s Degree in Biology from Kasetsart University (KU) in 2007. Since 2008 she has received a scholarship ?The Royal Golden Jubilee PH.D Program? from Thailand Research Fund (TRF) to fulfill her dissertation. Her research interest covers RNAi technology in orchid plants. She gained one year research experience at University of California at Riverside (UCR) in Prof. Shou-Wei Ding?s laboratory to study about RNAi mechanism in Arabidopsis and constructing cloning of orchid miRNA libraries.