title: Identification of Mild Freezing Shock Response Pathways in Barley Based on Transcriptome Profiling.
abstract: Low temperature is a major abiotic stress affecting crop growth and productivity. A better understanding of low temperature tolerance mechanisms is imperative for developing the crop cultivars with improved tolerance. We herein performed an Illumina RNA-sequencing experiment using two barley genotypes differing in freezing tolerance (Nure, tolerant and Tremois, sensitive), to determine the transcriptome profiling and genotypic difference under mild freezing shock treatment after a very short acclimation for gene induction. A total of 6474 differentially expressed genes, almost evenly distributed on the seven chromosomes, were identified. The key DEGs could be classified into six signaling pathways, i.e., Ca(2+) signaling, PtdOH signaling, CBFs pathway, ABA pathway, jasmonate pathway, and amylohydrolysis pathway. Expression values of DEGs in multiple signaling pathways were analyzed and a hypothetical model of mild freezing shock tolerance mechanism was proposed. Expression and sequence profile of HvCBFs cluster within Frost resistance-H2, a major quantitative trait locus on 5H being closely related to low temperature tolerance in barley, were further illustrated, considering the crucial role of HvCBFs on freezing tolerance. It may be concluded that multiple signaling pathways are activated in concert when barley is exposed to mild freezing shock. The pathway network we presented may provide a platform for further exploring the functions of genes involved in low temperature tolerance in barley.
authors.affiliation: Zhejiang Key Lab of Crop Germplasm, Department of Agronomy, Zhejiang University Hangzhou, China.
authors.forename: Xiaolei
authors.initials: X
authors.lastname: Wang
authors.affiliation: Zhejiang Key Lab of Crop Germplasm, Department of Agronomy, Zhejiang University Hangzhou, China.
authors.forename: Dezhi
authors.initials: D
authors.lastname: Wu
authors.affiliation: Zhejiang Key Lab of Crop Germplasm, Department of Agronomy, Zhejiang University Hangzhou, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Zhejiang Key Lab of Crop Germplasm, Department of Agronomy, Zhejiang University Hangzhou, China.
authors.forename: Jianbin
authors.initials: J
authors.lastname: Zeng
authors.affiliation: Zhejiang Key Lab of Crop Germplasm, Department of Agronomy, Zhejiang University Hangzhou, China.
authors.forename: Gulei
authors.initials: G
authors.lastname: Jin
authors.affiliation: Zhejiang Key Lab of Crop Germplasm, Department of Agronomy, Zhejiang University Hangzhou, China.
authors.forename: Zhong-Hua
authors.initials: ZH
authors.lastname: Chen
authors.affiliation: Zhejiang Key Lab of Crop Germplasm, Department of Agronomy, Zhejiang University Hangzhou, China.
authors.forename: Guoping
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Zhejiang Key Lab of Crop Germplasm, Department of Agronomy, Zhejiang University Hangzhou, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Dai
keywords: RNA-sequencing; barley (Hordeum vulgare L.); differentially expressed genes; freezing shock; signaling pathway