Ouyang Lejun, Wang Zechen, Li Limei, Chen Baoling
College of Biological and Food Engineering, Guangdong University of Petrochemical Technology, Maoming, China.
PeerJ. 2020 Mar 13;8:e8776. doi: 10.7717/peerj.8776. eCollection 2020.
In this study, we analyzed differences in the enzyme activities and transcriptomes of embryogenic and non-embryogenic calli to gain insights for improving the success of tissue culture-based breeding. A total of 2,856 differentially expressed genes (DEGs; 1,632 up-regulated and 1,224 down-regulated) were identified based on RNA sequencing and verified by reverse transcription quantitative polymerase chain reaction. Gene set enrichment analysis revealed that many of the up-regulated DEGs in embryogenic callus were enriched in the photosynthesis processes. Furthermore, the enzyme activity, hormone content, and cytokinin oxidase/dehydrogenase () gene expression analyses were found to be consistent with the transcriptome results. Cytokinin biosynthesis in -phenyl-'-[6-(2-chlorobenzothiazol)-yl] urea (PBU)-induced embryogenic callus increased owing to repression. Measurement of endogenous hormones by high-performance liquid chromatography revealed that, compared with non-embryogenic callus, in embryogenic callus, the indole-3-acetic acid, abscisic acid and trans-zeatin riboside content had significantly higher values of 129.7, 127.8 and 78.9 ng/g, respectively. Collectively, the findings of this study will provide a foundation for elucidating the molecular mechanisms underlying embryogenic callus differentiation and can potentially contribute to developing procedures aimed at enhancing the success of callus-based plant regeneration.
在本研究中，我们分析了胚性愈伤组织和非胚性愈伤组织的酶活性和转录组差异，以深入了解如何提高基于组织培养的育种成功率。基于RNA测序共鉴定出2856个差异表达基因（DEGs；1632个上调和1224个下调），并通过逆转录定量聚合酶链反应进行了验证。基因集富集分析表明，胚性愈伤组织中许多上调的DEGs富集于光合作用过程。此外，发现酶活性、激素含量和细胞分裂素氧化酶/脱氢酶（）基因表达分析与转录组结果一致。由于 抑制作用，在-苯基-'-[6-(2-氯苯并噻唑)-基]脲（PBU）诱导的胚性愈伤组织中细胞分裂素生物合成增加。通过高效液相色谱法测定内源激素表明，与非胚性愈伤组织相比，胚性愈伤组织中吲哚-3-乙酸、脱落酸和反式玉米素核糖苷含量分别显著更高，为129.7、127.8和78.9 ng/g。总体而言，本研究结果将为阐明胚性愈伤组织分化的分子机制提供基础，并可能有助于开发旨在提高基于愈伤组织的植物再生成功率的程序。
