Deciphering Novel Transcriptional Regulators of Soybean Hypocotyl Elongation Based on Gene Co-expression Network Analysis.

Zhikang Shen,Min Chen

doi:10.3389/fpls.2022.837130

Abstract

Hypocotyl elongation is the key step of soybean seed germination, as well an important symbol of seedling vitality, but the regulatory mechanisms remain largely elusive. To address the problem, bioinformatics approaches along with the weighted gene co-expression network analysis (WGCNA) were carried out to elucidate the regulatory networks and identify key regulators underlying soybean hypocotyl elongation at transcriptional level. Combining results from WGCNA, yeast one hybridization, and phenotypic analysis of transgenic plants, a cyan module significantly associated with hypocotyl elongation was discerned, from which two novel regulatory submodules were identified as key candidates underpinning soybean hypocotyl elongation by modulating auxin and light responsive signaling pathways. Taken together, our results constructed the regulatory network and identified novel transcriptional regulators of soybean hypocotyl elongation based on WGCNA, which provide new insights into the global regulatory basis of soybean hypocotyl elongation and offer potential targets for soybean improvement to acquire cultivars with well-tuned hypocotyl elongation and seed germination vigor.

Highlights

The consistency of seed germination and emergence is vital for large-scale agriculture, which reduces production cost and increase yield potential
In order to explore the global regulatory mechanisms underlying soybean hypocotyl elongation, we profiled the transcriptomes of the emerging hypocotyl and root tip tissue at 0, 1, and 5 days after imbibition (DAI) in the soybean cultivar “Williams 82” using RNA-seq (Supplementary Figure 1)
We identified a total of 97 modules via average linkage hierarchical clustering (Figure 1A)

Summary

Introduction

The consistency of seed germination and emergence is vital for large-scale agriculture, which reduces production cost and increase yield potential. Hypocotyl elongation, the later stage of seed germination, determines whether the seedlings can break the soil smoothly and simultaneously, affecting the field emergence rate and consistency. Lots of research effort has focused on deciphering the regulation mechanism of hypocotyl development, mainly in the model species Arabidopsis thaliana. Hypocotyl elongation in Arabidopsis thaliana is mainly driven by cell elongation. Effects of external environmental factors (light, temperature, gravity, etc.) as well endogenous hormones on hypocotyl elongation were well-studied (Deepika and Singh, 2020; Jiang et al, 2020). The current research results show that the internal and external signals are integrated through PHYTOCHROME INTERACTING FACTORs (PIFs) to

Methods

Results

Conclusion