title: Transcriptome responses to heat- and cold-stress in ladybirds (Cryptolaemus montrouzieri Mulasnt) analyzed by deep-sequencing.
abstract: BACKGROUND
  Changed temperature not only threaten agricultural production, but they also affect individual biological behavior, population and community of many insects, and consequently reduce the stability of our ecosystem. Insect's ability to respond to temperature stress evolved through a complex adaptive process, thus resulting in varied temperature tolerance among different insects. Both high and low extreme temperatures are detrimental to insect development since they constitute an important abiotic stress capable of inducing abnormal biological responses. Many studies on heat or cold tolerance of ladybirds have focused on measurements of physiological and biochemical indexes such as supercooling point, higher/lower lethal temperatures, survival rate, dry body weight, water content, and developmental duration. And studies of the molecular mechanisms of ladybird responses to heat or cold stress have focused on single genes, such as those encoding heat shock proteins, but has not been analyzed by transcriptome profiling.
  
  
  RESULTS
  In this study, we report the use of Digital Gene Expression (DGE) tag profiling to gain insight into transcriptional events associated with heat- and cold-stress in C. montrouzieri. About 6 million tags (49 bp in length) were sequenced in a heat stress group, a cold stress group and a negative control group. We obtained 687 and 573 genes that showed significantly altered expression levels following heat and cold shock treatments, respectively. Analysis of the global gene expression pattern suggested that 42 enzyme-encoding genes mapped to many Gene Ontology terms are associated with insect's response to heat- and cold-stress.
  
  
  CONCLUSIONS
  These results provide a global assessment of genes and molecular mechanisms involved in heat and cold tolerance.
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China. zhangyuhong1893@qq.com.|Guangdong Entomological Institue, Guangzhou, 510260, Guangdong, China. zhangyuhong1893@qq.com.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China. wuhongsheng126@126.com.|Guangdong Entomological Institue, Guangzhou, 510260, Guangdong, China. wuhongsheng126@126.com.
authors.forename: Hongsheng
authors.initials: H
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China. xjq998@yahoo.cn.
authors.forename: Jiaqin
authors.initials: J
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China. jiangrx85@foxmail.com.
authors.forename: Ruixin
authors.initials: R
authors.lastname: Jiang
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China. 1766285008@qq.com.
authors.forename: Congshuang
authors.initials: C
authors.lastname: Deng
authors.affiliation: State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, 510275, Guangdong, China. phzmfwz@sina.com.
authors.forename: Hong
authors.initials: H
authors.lastname: Pang
mesh_terms: D000818:Animals; D003080:Cold Temperature; D058639:Cold-Shock Response / Q000235:genetics*; D001517:Coleoptera / Q000145:classification / Q000201:enzymology / Q000235:genetics*; D017931:DNA Primers; D020869:Gene Expression Profiling / Q000379:methods; D015723:Gene Library; D063990:Gene Ontology; D017344:Genes, Insect / Q000502:physiology; D018869:Heat-Shock Response / Q000235:genetics*; D059014:High-Throughput Nucleotide Sequencing / Q000379:methods*; D006358:Hot Temperature; D060888:Real-Time Polymerase Chain Reaction; D017422:Sequence Analysis, DNA / Q000379:methods; D013312:Stress, Physiological / Q000235:genetics; D059467:Transcriptome
chemical_list: D017931:DNA Primers