Transcriptome analysis revealed expression of genes related to anthocyanin biosynthesis in eggplant (Solanum melongena L.) under high-temperature stress

Shengmei Zhang,Dingshi Zha,Zuofen Yang,Aidong Zhang,Yuelin Zhu,Zongwen Zhu,Xuexia Wu

doi:10.1186/s12870-019-1960-2

Abstract

BackgroundAnthocyanin synthesis is affected by many factors, among which temperature is an important environmental factor. Eggplant is usually exposed to high temperatures during the cultivation season in Shanghai, China. Therefore,RNA -seq analysis was used to determine the effects of high-temperature stress on gene expression in the anthocyanin biosynthetic pathway of eggplant (Solanum melongena L.).ResultsWe tested the heat-resistant cultivar ‘Tewangda’. The plants were incubated at 38 °C and 45 °C, and the suitable temperature for eggplant growth was used as a control. The treatment times were 3 h and 6 h. The skin of the eggplant was taken for transcriptome sequencing, qRT-PCR assays and bioinformatic analysis. The results showed that 770 genes were differentially expressed between different treatments. Gene Ontology (GO) database and Kyoto Encyclopedia of Genes and Genomes (KEGG) database analyses identified 16 genes related to anthocyanin biosynthesis, among which CHSB was upregulated. Other genes, including BHLH62, MYB380, CHI3, CHI, CCOAOMT, AN3, ACT-2, HST, 5MA-T1, CYP75A2, ANT17, RT, PAL2, and anthocyanin 5-aromatic acyltransferase were downregulated. In addition, the Myb family transcription factor PHL11 was upregulated in the CK 3 h vs 45 °C 3 h, CK 3 h vs 38 °C 3 h, and CK 6 h vs 38 °C 6 h comparisons, and the transcription factor bHLH35 was upregulated in the CK 3 h vs 38 °C 3 h and CK 6 h vs 38 °C 6 h comparisons.ConclusionThese results indicated that high temperature will downregulate most of the genes in the anthocyanin biosynthetic pathway of eggplant. Our data have a reference value for the heat resistance mechanism of eggplant and can provide directions for molecular breeding of heat-resistant germplasm with anthocyanin content in eggplant.

Highlights

Anthocyanin synthesis is affected by many factors, among which temperature is an important environmental factor
In plants of the genus Solanum, the genes CAPRICE (MYB) and GLABRA3 in Arabidopsis and tomato were assessed; the results indicated that CAPRICE inhibits the accumulation of anthocyanins, while GLABRA3 promotes the accumulation of anthocyanins, which are regulated by key genes
Analysis of differentially expressed genes associated with Hsps and Hsfs The results showed that 65 DEGs about Hsps and Hsfs were identified in the CK 6 h vs 45 °C 6 h were more than other groups,but only three associated genes were identified in the 45 °C 3 h vs 45 °C 6 h.We identified 24 Hsps genes and 4 Hsfs gens were differentially expressed in the CK 3 h vs 45 °C 3 h, CK 3 h vs 38 °C 3 h, CK 6 h vs 45 °C 6 h and CK 6 h vs 38 °C 6 h comparisons

Summary

Introduction

Anthocyanin synthesis is affected by many factors, among which temperature is an important environmental factor. RNA -seq analysis was used to determine the effects of high-temperature stress on gene expression in the anthocyanin biosynthetic pathway of eggplant (Solanum melongena L.). In an analysis of eggplant samples, we found that green-skinned eggplants containing less anthocyanin content are more susceptible to oxidative blackening than purple-skinned eggplants. These metabolites are widely found in plants and have important roles, in addition to being the main substance responsible for flower color and fruit color. Anthocyanins protect the leaf’s photosynthetic system from damage [5] These compounds play a positive role in plant resistance to stress. These metabolites can reduce the degree of obesity by reducing adipose tissue [10]

Methods

Results

Discussion

Conclusion