title: Identification and comparative analysis of differentially expressed miRNAs in leaves of two wheat (Triticum aestivum L.) genotypes during dehydration stress.
abstract: BACKGROUND
  MicroRNAs (miRNAs) play critical roles in the processes of plant growth and development, but little is known of their functions during dehydration stress in wheat. Moreover, the mechanisms by which miRNAs confer different levels of dehydration stress tolerance in different wheat genotypes are unclear.
  
  
  RESULTS
  We examined miRNA expressions in two different wheat genotypes, Hanxuan10, which is drought-tolerant, and Zhengyin1, which is drought-susceptible. Using a deep-sequencing method, we identified 367 differentially expressed miRNAs (including 46 conserved miRNAs and 321 novel miRNAs) and compared their expression levels in the two genotypes. Among them, 233 miRNAs were upregulated and 10 were downregulated in both wheat genotypes after dehydration stress. Interestingly, 13 miRNAs exhibited opposite patterns of expression in the two wheat genotypes, downregulation in the drought-tolerant cultivar and upregulation in the drought-susceptible cultivar. We also identified 111 miRNAs that were expressed predominantly in only one or the other genotype after dehydration stress. We verified the expression patterns of a number of representative miRNAs using qPCR analysis and northern blot, which produced results consistent with those of the deep-sequencing method. Moreover, monitoring the expression levels of 10 target genes by qPCR analysis revealed negative correlations with the levels of their corresponding miRNAs.
  
  
  CONCLUSIONS
  These results indicate that differentially expressed patterns of miRNAs between these two genotypes may play important roles in dehydration stress tolerance in wheat and may be a key factor in determining the levels of stress tolerance in different wheat genotypes.
authors.affiliation: College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China. ml25900@126.com.|Collaborative Innovation Center of Henan Grain Crops, Zhengzhou, 450002, China. ml25900@126.com.|National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, 450002, China. ml25900@126.com.
authors.forename: Xingli
authors.initials: X
authors.lastname: Ma
authors.affiliation: College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China. yuzexinhau@126.com.|Collaborative Innovation Center of Henan Grain Crops, Zhengzhou, 450002, China. yuzexinhau@126.com.|National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, 450002, China. yuzexinhau@126.com.
authors.forename: Zeyu
authors.initials: Z
authors.lastname: Xin
authors.affiliation: College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China. qiangzhiwang001@126.com.|Collaborative Innovation Center of Henan Grain Crops, Zhengzhou, 450002, China. qiangzhiwang001@126.com.|National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, 450002, China. qiangzhiwang001@126.com.
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Wang
authors.affiliation: College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China. qhyang1966@126.com.|Collaborative Innovation Center of Henan Grain Crops, Zhengzhou, 450002, China. qhyang1966@126.com.|National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, 450002, China. qhyang1966@126.com.
authors.forename: Qinghua
authors.initials: Q
authors.lastname: Yang
authors.affiliation: College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China. guoshulei003@126.com.|Collaborative Innovation Center of Henan Grain Crops, Zhengzhou, 450002, China. guoshulei003@126.com.|National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, 450002, China. guoshulei003@126.com.
authors.forename: Shulei
authors.initials: S
authors.lastname: Guo
authors.affiliation: College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China. xyguonky@126.com.|Collaborative Innovation Center of Henan Grain Crops, Zhengzhou, 450002, China. xyguonky@126.com.|National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, 450002, China. xyguonky@126.com.
authors.forename: Xiaoyang
authors.initials: X
authors.lastname: Guo
authors.affiliation: College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China. lirucao1988@126.com.|Collaborative Innovation Center of Henan Grain Crops, Zhengzhou, 450002, China. lirucao1988@126.com.|National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, 450002, China. lirucao1988@126.com.
authors.forename: Liru
authors.initials: L
authors.lastname: Cao
authors.affiliation: College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China. linlab1@126.com.|Collaborative Innovation Center of Henan Grain Crops, Zhengzhou, 450002, China. linlab1@126.com.|National Key Laboratory of Wheat and Maize Crop Science, Zhengzhou, 450002, China. linlab1@126.com.
authors.forename: Tongbao
authors.initials: T
authors.lastname: Lin
mesh_terms: D002681:China; D003890:Desiccation; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D005838:Genotype; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D017433:Protein Structure, Secondary; D013312:Stress, Physiological; D014908:Triticum / Q000235:genetics / Q000502:physiology*
chemical_list: D035683:MicroRNAs