Differential Expression of microRNAs in Maize Inbred and Hybrid Lines during Salt and Drought Stress

Yeqin Kong,Axel A Elling,Beibei Chen,Xingwang Deng

doi:10.4236/ajps.2010.12009

Abstract

Here, we analyzed whether the microRNA (miRNA) expression levels differ between maize inbred lines B73 and Mo17 and their reciprocal hybrids under salt and drought stress. We found that miR156, miR164, miR166, miR168, miR171 and miR319 are differentially expressed under abiotic stress. Interestingly, Mo17 × B73 showed the strongest change in miRNA expression in response to salt or drought stress, and was also the most resilient line when under abiotic stress in terms of water loss. In summary, our findings open the possibility that differential miRNA expression levels might be involved in heightened stress tolerance in maize hybrids.

Highlights

MicroRNAs are non-coding RNAs approximately 20-24 nucleotides in length that act as negative post-transcriptional regulators [1,2]
We determined whether seedlings of maize inbred lines B73 and Mo17 and their reciprocal F1 hybrids show differential miRNA expression patterns in response to salt and drought stress and whether heightened stress tolerance in F1 hybrids correlates with changes in miRNA abundance
We found that while the water content of droughtstressed plants continued to decrease over time, the water content of salt-stressed plants increased after reaching a minimum at 12 h

Summary

Introduction

MicroRNAs (miRNAs) are non-coding RNAs approximately 20-24 nucleotides in length that act as negative post-transcriptional regulators [1,2]. It is well documented that the F1 hybrid progeny of inbred parental lines shows superior performance and stress tolerance compared to either parent [10,11,12]. This effect is called heterosis and is widely exploited in plant breeding. We determined whether seedlings of maize inbred lines B73 and Mo17 and their reciprocal F1 hybrids show differential miRNA expression patterns in response to salt and drought stress and whether heightened stress tolerance in F1 hybrids correlates with changes in miRNA abundance

Methods

Results

Conclusion