转录组分析揭示了巴西橡胶树体细胞胚胎发生分子机制的新见解。

Transcriptomes analysis reveals novel insight into the molecular mechanisms of somatic embryogenesis in Hevea brasiliensis.

机构信息

Key Laboratory of Biology and Genetic Resources of Tropical Crops, Ministry of Agriculture, Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Sciences, No.4 Xueyuan Road, Haikou, 571101, China.

School of Life and Pharmaceutical Sciences, Hainan University, Haikou, 570228, China.

出版信息

BMC Genomics. 2021 Mar 12;22(1):183. doi: 10.1186/s12864-021-07501-9.

BACKGROUND

Somatic embryogenesis (SE) is a promising technology for plant vegetative propagation, which has an important role in tree breeding. Though rubber tree (Hevea brasiliensis Muell. Arg.) SE has been founded, few late SE-related genes have been identified and the molecular regulation mechanisms of late SE are still not well understood.

RESULTS

In this study, the transcriptomes of embryogenic callus (EC), primary embryo (PE), cotyledonary embryo (CE), abnormal embryo (AE), mature cotyledonary embryo (MCE) and withered abnormal embryo (WAE) were analyzed. A total of 887,852,416 clean reads were generated, 85.92% of them were mapped to the rubber tree genome. The de novo assembly generated 36,937 unigenes. The differentially expressed genes (DEGs) were identified in the pairwise comparisons of CE vs. AE and MCE vs. WAE, respectively. The specific common DEGs were mainly involved in the phytohormones signaling pathway, biosynthesis of phenylpropanoid and starch and sucrose metabolism. Among them, hormone signal transduction related genes were significantly enriched, especially the auxin signaling factors (AUX-like1, GH3.1, SAUR32-like, IAA9-like, IAA14-like, IAA27-like, IAA28-like and ARF5-like). The transcription factors including WRKY40, WRKY70, MYBS3-like, MYB1R1-like, AIL6 and bHLH93-like were characterized as molecular markers for rubber tree late SE. CML13, CML36, CAM-7, SERK1 and LEAD-29-like were also related to rubber tree late SE. In addition, histone modification had crucial roles during rubber tree late SE.

CONCLUSIONS

This study provides important information to elucidate the molecular regulation during rubber tree late SE.

背景

体细胞胚胎发生（SE）是一种有前途的植物营养繁殖技术，在树木育种中具有重要作用。尽管已发现橡胶树（Hevea brasiliensis Muell. Arg.）的 SE，但很少鉴定到晚期 SE 相关基因，并且晚期 SE 的分子调控机制仍不清楚。

结果

本研究分析了胚性愈伤组织（EC）、原胚（PE）、子叶胚（CE）、异常胚（AE）、成熟子叶胚（MCE）和枯萎异常胚（WAE）的转录组。共产生了 887,852,416 条清洁读数，其中 85.92%映射到橡胶树基因组上。从头组装生成了 36,937 条 unigenes。分别在 CE 与 AE 和 MCE 与 WAE 的成对比较中鉴定出差异表达基因（DEGs）。特定的共同 DEGs 主要涉及植物激素信号通路、苯丙烷生物合成和淀粉和蔗糖代谢。其中，激素信号转导相关基因显著富集，特别是生长素信号因子（AUX-like1、GH3.1、SAUR32-like、IAA9-like、IAA14-like、IAA27-like、IAA28-like 和 ARF5-like）。转录因子包括 WRKY40、WRKY70、MYBS3-like、MYB1R1-like、AIL6 和 bHLH93-like，被表征为橡胶树晚期 SE 的分子标记。CML13、CML36、CAM-7、SERK1 和 LEAD-29-like 也与橡胶树晚期 SE 有关。此外，组蛋白修饰在橡胶树晚期 SE 中具有关键作用。