Research Accomplishment Reports 2009

Roles of MicroRNA Structures in Plant RNA Silencing

G. Tang
Department of Plant and Soil Sciences

 

Non-Technical Summary

MicroRNAs (miRNAs) are recently discovered endogenous small RNAs of ~22 nucleotides in plants and animals. They regulate gene expression after the gene transcription by cleaving the mRNA and prevent mRNA from translation into proteins. Various miRNAs from both plants and animals were cloned and their precursors and genes were identified. Stem-loop RNA structure is the hallmark of miRNA precursors and helps produce highly efficient RNA silencing triggers, the miRNAs. Here we propose to dissect the miRNA precursor structures using informatics approach and find rules of their structures in RNA silencing. This will involve the establishment of a miRNA structure database and its analysis in detail. The rules found from the database analysis will be applied to design highly efficient small RNAs or small RNA vectors for silencing any genes of interest. The proposed activities also include a training of three graduate students and several undergraduate students.

2009 Project Description

We have completed the analysis of pre-miRNA structures and generated practical rules for plant RNA silencing using modified two-hit artificial miRNAs (amiRNAs) to silence any genes of interest. The silencing efficiency reached to 90% compared to tradition amiRNA technology. We are now applying this technology to silence families of transcription factor genes in Arabidopsis. Translational application to crops will be conducted in the future for crop improvement.

2009 Impact

Outcomes:

1. Novel two-hit amiRNA vector for gene silencing in plants;

2. Functional genomics for plant transcription factor genes.

Impact:

1. Tools for plant gene functions;

2. Crop improvement.

2009 Publications

Xiaoyun Jia, Wang-Xia Wang, Ligang Ren, Qi-Jun Chen, Venugopal Mendu, Benjamin Willcut, Randy Dinkins, Xiaoqing Tang, and Guiliang Tang (2009) Differential and dynamic regulation of miR398 and its targets in response to ABA and salt stress in Populus tremula and Arabidopsis thaliana. Plant Molecular Biology 71: 51-59.

Xiaoyun Jia, Ligang Ren, Qi-Jun Chen, Runzhi Li and Guiliang Tang (2009) UV-B responsive microRNAs in Populus tremula. J. of Plant Physiology 166: 2046-2057.

Ricky Lewis, Venugopal Mendu, David McNear, and Guiliang Tang (2009) Roles of microRNAs in Plant Abiotic Stress, Molecular Techniques in Crop Improvement. 2nd Edition, edited by S. Mohan Jain and D.S. Brar. Springer Netherlands, pp 357-372.

Mian Gu, Ke Xu, Aiqun Chen, Yiyong Zhu, Guiliang Tang, and Guohua Xu (2010) Expression Analysis Suggests Potential Roles of microRNAs for Phosphate and Arbuscular Mycorrhizal Signaling in Solanum lycopersicum. Physiol Plant.138(2):226-37.

Xiaoyun Jia, Venugopal Mendu, and Guiliang Tang (2010) An array platform for identification of stress-responsive miRNAs in plants, "Methods in Molecular Biology; Plant Stress Tolerance- Methods and Protocols" edited by Ramanjulu Sunkar, Oklohoma State University, Stillwater, OK, USA. HUMANA PRESS.