Open Access

ARTICLE

The Regulatory Roles of microRNAs and Associated Target Genes during Early Somatic Embryogenesis in Liriodendron Sino-Americanum

by Dan Wang¹, Fengjuan Lu¹, Pengkai Wang¹, Jiaji Zhang¹, Lu Lu¹, Yan Zhen¹, Ye Lu¹, Tielong Cheng², Jisen Shi^1,*, Jinhui Chen^1,*

1 Key Laboratory of Forest Genetics & Biotechnology of Ministry of Education of China, Co-Innovation Center for Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing, 210037, China
2 College of Biology and the Environment, Nanjing Forestry University, Nanjing, 210037, China

* Corresponding Authors: Jisen Shi. Email: ; Jinhui Chen. Email:

(This article belongs to the Special Issue: Tree Somatic Embryogenesis and Application)

Phyton-International Journal of Experimental Botany 2021, 90(5), 1445-1463. https://doi.org/10.32604/phyton.2021.015499

Received 22 December 2020; Accepted 29 March 2021; Issue published 27 May 2021

Abstract

Somatic cells respond to considerable stress, and go through a series of phytohormone pathways, then forming an embryo. The developmental process is recorded as somatic embryogenesis (SE). One of the key components regulating SE are the microRNAs (miRNAs). Despite previous studies, it is still not clear exactly how miRNAs exert their function of regulating targets during conditionally activated early SE. Here, we use Liriodendron sino-americanum as a model system and perform a combined analysis of microfluidic chips and degradome sequencing to study this process. We identified a total of 386 conserved miRNAs and 153 novel miRNAs during early SE. According to the ANOVA test, 239 miRNAs showed 12 distinct expression patterns. Through degradome sequencing, 419 targets and 198 targets were identified for 136 known miRNAs and 37 novel miRNAs, respectively. Gene Ontology (GO) and metabolism pathway enrichment analysis revealed that these targets were significantly involved in oxidation-reduction processes, calmodulin-mediated signal transduction pathways and carbohydrate metabolism. The genes that were related to stress responses, phytohormone pathways and plant metabolism were identified within the targets of miR319, miR395, miR408, miR472, miR482, miR390, miR2055, miR156, miR157, miR171, miR396, miR397, miR529, miR535 and miR159. According to promoter analysis, various cis-acting elements related to plant growth and development, phytohormones response and stress response were present in the promoter of the miRNAs. The differential expression patterns of 11 miRNA-target modules were confirmed by real-time quantitative PCR. The study demonstrated that the miRNA plays an important role in the early SE process by regulating its target and then participating in carbohydrate metabolism and stress response. It also provided a valuable resource for further research in determining the genetic mechanism of SE, and then facilitating breeding programs on plants.

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Supplementary Material

Supplementary Material File

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