High-Throughput Sequencing Reveals H2O2Stress-Associated MicroRNAs and a Potential Regulatory Network inBrachypodium distachyonSeedlings.
Oxidative stress in plants can be triggered by many environmental stress factors, such as drought and salinity.Brachypodium distachyonis a model organism for the study of biofuel plants and crops, such as wheat. Although recent studies have found many oxidative stress response-related proteins, the mechanism of microRNA (miRNA)-mediated oxidative stress response is still unclear. Using next generation high-throughput sequencing technology, the small RNAs were sequenced from the model plantB. distachyon21 (Bd21) under H2O2stress and normal growth conditions. In total, 144 knownB. distachyonmiRNAs and 221 potential new miRNAs were identified. Further analysis of potential new miRNAs suggested that 36 could be clustered into known miRNA families, while the remaining 185 were identified asB. distachyon-specific new miRNAs. Differential analysis of miRNAs from the normal and H2O2stress libraries identified 31 known and 30 new H2O2stress responsive miRNAs. The expression patterns of seven representative miRNAs were verified by reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis, which produced results consistent with those of the deep sequencing method. Moreover, we also performed RT-qPCR analysis to verify the expression levels of 13 target genes and the cleavage site of 5 target genes by known or novel miRNAs were validated experimentally by 5' RACE. Additionally, a miRNA-mediated gene regulatory network for H2O2stress response was constructed. Our study identifies a set of H2O2-responsive miRNAs and their target genes and reveals the mechanism of oxidative stress response and defense at the post-transcriptional regulatory level.
College of Life Science, Capital Normal UniversityBeijing, China; Department of Oral and Craniofacial Molecular Biology, VCU Philips Institute for Oral Health Research, School of Dentistry, Virginia Commonwealth UniversityRichmond, VA, USA.
Dong-Wen
DW
Lv
College of Life Science, Capital Normal University Beijing, China.
Shoumin
S
Zhen
College of Life Science, Capital Normal University Beijing, China.
Geng-Rui
GR
Zhu
College of Life Science, Capital Normal University Beijing, China.
Yan-Wei
YW
Bian
College of Life Science, Capital Normal University Beijing, China.
Guan-Xing
GX
Chen
College of Life Science, Capital Normal University Beijing, China.
Cai-Xia
CX
Han
State Agriculture Biotechnology Centre, Murdoch University Perth, WA, Australia.
Zi-Tong
ZT
Yu
College of Life Science, Capital Normal University Beijing, China.
Yue-Ming
YM
Yan
Bd21; H2O2 stress; high-throughput sequencing; microRNA; regulatory network