Advanced Biotechnology and Breeding Centre, Malaysian Palm Oil Board, No. 6, Persiaran Institusi, Bandar Baru Bangi, 43000, Kajang, Selangor, Malaysia.
Institute of Plant Biology, National Taiwan University, No. 1, Section 4, Roosevelt Road, 10617, Taipei, Taiwan, ROC.
Mol Biotechnol. 2022 Jul;64(7):743-757. doi: 10.1007/s12033-022-00450-y. Epub 2022 Feb 2.
EgENOD93 was first identified in a cDNA microarray study of oil palm tissue culture where it was highly expressed in leaf explants with embryogenic potential. Functional characterization via an RNA interference study of its orthologue in Medicago truncatula demonstrated a significant role of this gene in somatic embryo formation. In this study, EgENOD93 was overexpressed in the important model plant Arabidopsis thaliana to investigate the embryogenic potential of EgENOD93 transgenic Arabidopsis explants compared to explants from control plants (pMDC140 and WT). Experiments using leaf explants revealed higher numbers of regenerated shoots at day 27 in all the homozygous transgenic Arabidopsis cultures (Tg01, Tg02 and Tg03) compared to controls. The expression level of EgENOD93 in Arabidopsis cultures was quantified using reverse transcription quantitative real-time PCR (RT-qPCR). The results supported the overexpression of this gene in transgenic Arabidopsis cultures, with 6 and 10 times higher expression of EgENOD93 in callus at Day 9 and Day 20, respectively. Overall, the results support the role of EgENOD93 in the enhancement of shoot regeneration in transgenic Arabidopsis. This together with the previous results observed in oil palm and Medicago truncatula suggests that ENOD93 plays a key role in the induction of somatic embryogenesis. A similarity to early nodulation-like ontogeny is possible.
EgENOD93 最初是在油棕组织培养的 cDNA 微阵列研究中被鉴定出来的，在具有胚胎发生潜力的叶外植体中它的表达水平很高。通过对 Medicago truncatula 中其同源物的 RNA 干扰研究进行功能表征，表明该基因在体细胞胚胎形成中具有重要作用。在这项研究中，EgENOD93 在重要的模式植物拟南芥中过表达，以研究与对照植物（pMDC140 和 WT）相比，EgENOD93 转基因拟南芥外植体的胚胎发生潜力。使用叶片外植体的实验表明，所有纯合转基因拟南芥培养物（Tg01、Tg02 和 Tg03）在第 27 天再生芽的数量比对照植物更高。使用反转录定量实时 PCR（RT-qPCR）定量了拟南芥培养物中 EgENOD93 的表达水平。结果支持该基因在转基因拟南芥培养物中的过表达，在第 9 天和第 20 天的愈伤组织中，EgENOD93 的表达水平分别高出 6 倍和 10 倍。总体而言，这些结果支持 EgENOD93 在增强转基因拟南芥中芽再生中的作用。这与在油棕和 Medicago truncatula 中观察到的先前结果一起表明，ENOD93 在体细胞胚胎发生的诱导中起着关键作用。可能存在类似于早期结瘤样发生的相似性。
