Comparative transcriptome analysis reveals differential transcription in heat-resistant and heat-sensitive jujube cultivars under heat stress. Comparative transcriptome analysis reveals differential transcription in heat-resistant and heat-sensitive jujube cultivars under heat stress

Jujube (Ziziphus jujuba Mill.) is an economically and agriculturally significant fruit crop and is widely cultivated throughout the world. Heat stress has recently become one of the major abiotic stresses limiting plant growth and productivity. However, there are few studies on the transcriptome profiling of jujube subjected to heat stress. In this study, we analyzed the physiological and transcriptomic changes of heat-resistant jujube cultivar ‘HR’ and heat-sensitive cultivar ‘HS’ caused by high temperature stress. We statistically determined 984, 1468, 1727 and 2098 differentially expressed genes (DEGs) between ‘HR’ and ‘HS’ after 0, 1, 3, 5 d of heat stress, respectively. Gene Ontology (GO) enrichment analysis indicated that Aa great deal of heat-responsive genes were identified in these DEGs by Gene Ontology (GO) enrichment analysis. It suggests the distinct molecular mechanism of jujube response to heat stress. Furthermore, we validated the expression profiles of 12 candidates using qRT-PCR to further confirm the accuracy of the RNA-seq data. These results will advance our knowledge of the genes involved in the complex regulatory networks of heat stress and provide genetic resources for further improving the heat tolerance in jujube. Overall design: Transcriptome analysis for a jujuebe heat-sensitive cultivar under heat stress,in triplicate, using Illumina HiSeq X-ten.

枣（Ziziphus jujuba Mill.）是一种兼具重要经济与农业价值的果树作物，在全球范围内广泛栽培。近年来，热胁迫已成为限制植物生长与产量的主要非生物胁迫之一。然而，目前针对热胁迫下枣转录组特征的研究仍较为匮乏。本研究针对耐热枣品种‘HR’与热敏感品种‘HS’，分析了高温胁迫诱导的生理与转录组变化。经统计学分析，在热胁迫处理0、1、3、5 d后，‘HR’与‘HS’之间分别存在984、1468、1727及2098个差异表达基因（differentially expressed genes, DEGs）。经基因本体（Gene Ontology, GO）富集分析，于上述DEGs中鉴定出大量热响应基因，这表明枣应对热胁迫的分子机制具有特异性。此外，本研究采用实时荧光定量聚合酶链反应（qRT-PCR）对12个候选基因的表达谱进行验证，以进一步确认RNA测序（RNA-seq）数据的准确性。本研究结果有助于加深我们对热胁迫复杂调控网络中相关基因的认知，并为进一步改良枣的耐热性提供了遗传资源。整体实验设计：以热敏感枣品种为材料，在高温胁迫下进行转录组分析，设置3次生物学重复，测序平台为Illumina HiSeq X-ten。