Transcriptomic and metabolic analyses revealed the modulatory effect of vernalization on glucosinolate metabolism in radish (Raphanus sativus L.)

Adji Baskoro Dwi Nugroho,Dong-Hwan Kim,Sang Woo Lee,Jongkee Kim,Aditya Nurmalita Pervitasari,Heewon Moon,Dasom Choi

doi:10.1038/s41598-021-03557-5

Adji Baskoro Dwi Nugroho, Dong-Hwan Kim + Show 5 more

Open Access

https://doi.org/10.1038/s41598-021-03557-5

Copy DOI

Abstract

Vernalization is the process by which long-term cold like winter triggers transition to flowering in plants. Many biennial and perennial plants including Brassicaceae family plants require vernalization for floral transition. Not only floral transition, but dynamic physiological and metabolic changes might also take place during vernalization. However, vernalization-mediated metabolic change is merely investigated so far. One of secondary metabolites found in Brassiceceae family plants is glucosinolates (GSLs). GSLs provides defense against pathogens and herbivores attack in plants and also exhibits inhibitory activity against human cancer cell. Profiles of GSLs are highly modulated by different environmental stresses in Brassciaceae family plants. To grasp the effect of vernalization on GSLs metabolic dynamics in radish (Raphanus sativus L.), we performed transcriptomic and metabolic analysis during vernalization in radish. Through transcriptome analysis, we found many GSLs metabolic genes were significantly down-regulated by vernalization in radish plants. Ultra-High Performance Liquid Chromatography analysis also revealed that GSLs compounds were substantially reduced in vernalized radish samples compared to non-vernalized radish samples. Furthermore, we found that repressive histone modification (i.e. H3K27me3) is involved in the modulation of GSLs metabolism via epigenetic suppression of Glucoraphasatin Synthase 1 (GRS1) during vernalization in radish. This study revealed that GSLs metabolism is modulated by vernalization, suggestive of a newly identified target of vernalization in radish.

Highlights

Vernalization is the process by which long-term cold like winter triggers transition to flowering in plants
The results showed that three MYB28 homologs (RsMYB28a, RSG16088; RsMYB28b, RSG23384; RsMYB28c, RSG53581) and two MYB29 homologs (RsMYB29a, RSG00789; RsMYB29b, RSG09585), which were involved in aliphatic GSLs biosynthesis, were identified in the radish genome
Since RsGRS1 was suppressed during vernalization, we investigated whether vernalization-mediated suppression of RsGRS1 is through epigenetic histone modification

Summary

Introduction

Vernalization is the process by which long-term cold like winter triggers transition to flowering in plants. We found many GSLs metabolic genes were significantly down-regulated by vernalization in radish plants. Abbreviations PGT Progoitrin GER Glucoerucin GRH Glucoraphasatin GRE Glucoraphenin GRA Glucoraphanin SFA Sulforaphane TFs Transcription factors family GRS1 Glucoraphasatin synthase 1 FLC Flowering locus C FMOgs-OXs Flavin monooxygenase UHPLC Ultra-high performance liquid chromatography RT-qPCR Quantitative reverse transcription PCR. Plants synthesize several defensive compounds such as alkaloids, benzoxanoids, terpenoids, and glucosinolates (GSLs)[3] to cope with stress and harsh environmental conditions. Among these secondary metabolites, GSLs and their hydrolyzed products, which are mainly found in plants of family Brassicaceae, including radish, play a defensive role against diverse stresses. Further conversion of GRH to glucoraphenin (GRE) is catalyzed by a subgroup of flavin-containing monooxygenase family proteins referred to as FMOgs-OXs (Fig. 1)

Objectives

Methods

Results

Conclusion