摘要
种子休眠与萌发受到内源激素和外界环境等多种因素的调控.生产上常采用清水浸泡和低温砂藏层积处理方法打破梨种子休眠进程,促进种子萌发.为解析梨种子休眠解除的分子机制,以翠冠梨干种子为研究对象,通过清水浸泡6 h再低温砂藏60 d进行催芽.对该过程17个时期种仁ABA含量进行测定,结果显示在种子浸泡过程和低温砂藏7 d阶段ABA含量整体呈现下降趋势,随后趋于稳定.选取其中7个关键时期样品进行转录组测序,GO分析结果显示差异基因被分配到40个功能组,KEGG分析结果显示差异基因主要富集在核糖体、多样化环境中微生物代谢、碳代谢、辅因子的生物合成和氨基酸的生物合成通路.通过转录组测序获得的基因FPKM值和ABA含量数据构建共表达网络,结果显示11个基因(Pbr009501、Pbr016256、Pbr011612、Pbr033750、Pbr015393、Pbr000885、Pbr037755、Pbr039726、Pbr020341、Pbr003677 和 Pbr015873)与ABA含量的相关性均极高,相关性系数达到0.91～0.96.研究结果为挖掘梨种子休眠和萌发过程调控ABA水平的关键基因提供了重要信息.
Abstract
Seed dormancy and germination are precisely regulated by various factors such as endogenous hor-mones and external environment.Clean water soaking and low temperature stratification treatment are often used in production to break the dormancy process and promote germination of pear seeds.To analyze the mo-lecular mechanism of dormancy release in pear seeds,Cuiguan pear seeds were soaked in clean water for 6 hours and then stored in sand under low-temperature for 60 days to accelerate the germination.The ABA con-tent of pear seeds at 17 stages of this process was detected.The ABA content showed a decreasing trend dur-ing the seed soaking process and 7 days of low-temperature sand storage and then remained stable.Samples in seven key periods were selected for RNA sequencing.The results of GO analysis showed that differentially ex-pressed genes were assigned into 40 functional groups.The results of KEGG analysis showed that differential-ly expressed genes were mainly enriched in five pathways,including ribosome,microbial metabolism in diverse environments,carbon metabolism,biosynthesis of cofactors,and biosynthesis of amino acids.A co-expression network was constructed using transcriptome and ABA content data.The results showed that expressions of 11 genes(Pbr009501,Pbr016256,Pbr011612,Pbr033750,Pbr015393,Pbr000885,Pbr037755,Pbr039726,Pbr020341,Pbr003677 and Pbr015873)were highly correlated with ABA content,with correla-tion coefficients ranging from 0.91 to 0.96.These results provide important information for exploring the key genes that regulate ABA levels during pear seed dormancy and germination processes.
基金项目
江苏省教育科学"十三五"规划青年专项重点资助项目(C-a/2020/01/14)
国家科技期刊平台
NSTL
万方数据