Integrative Analysis of Long- and Short-Read Transcriptomes Identify the Regulation of Terpenoids Biosynthesis Under Shading Cultivation in Oenanthe javanica

Abstract

Water dropwort (Oenanthe javanica) is a popular vegetable with high nutritional value and distinctive flavor. The flavor is mainly correlate with the biosynthesis of terpenoids. Shading cultivation was used to improve the flavor in the production of water dropwort. However, the changes of terpenoids and the genes involved in terpenoids biosynthesis under shading treatment remains unclear. In this study, the long- and short-reads transcriptomes of water dropwort were constructed. In total, 57,743 non-redundant high-quality transcripts were obtained from the transcriptome. 28,514 SSRs were identified from non-redundant transcripts and the mono-nucleotide repeats were the most abundant SSRs. The lncRNAs of water dropwort were recognized and their target genes were predicted. The volatile compound contents in petioles and leaf blades of water dropwort were decreased after the shading treatment. The DEGs analysis was performed to identify the terpenoids biosynthesis genes. The results indicated that 5,288 DEGs were differentially expressed in petiole, of which 22 DEGs were enriched in the terpenoids backbone biosynthesis pathway. A total of 12 DEGs in terpenoids biosynthesis pathway were selected and further verified by qRT-PCR assay, demonstrating that the terpenoids biosynthesis genes were down-regulated under shading treatment. Here, the full-length transcriptome was constructed and the regulatory genes related to terpenoids biosynthesis in water dropwort were also investigated. These results will provide useful information for future researches on functional genomics and terpenoids biosynthesis mechanism in water dropwort.

Metabolomics Analysis Reveals Metabolites and Metabolic Pathways Involved in the Growth and Quality of Water Dropwort [Oenanthe javanica (Blume) DC.] under Nutrient Solution Culture

“…Previous studies have found that the unique aroma of water dropwort is related to the accumulation of secondary metabolites, including terpenoids, alcohols, etc. [ 7 , 9 , 60 ]. Our previous research has found that shading cultivation was used to improve the flavor in the production of water dropwort.…”

“…Our previous research has found that shading cultivation was used to improve the flavor in the production of water dropwort. The terpenoid biosynthesis genes were down−regulated under the shading treatment [ 9 ]. In addition, GC−MS technology was used to determine and analyze the volatile substances related to the flavor of water dropwort [ 7 ].…”

“…Due to its unique aroma and taste, some Southeast Asian countries use the leaves as spices for flavoring [ 8 ]. Water dropwort prefers the cold, and the suitable growth temperature is 12–24 °C [ 9 ]. Water dropwort has usually been cultivated by deep-water cultivation, shallow-water cultivation, shading cultivation and other cultivation methods [ 9 , 10 ].…”

“…Water dropwort prefers the cold, and the suitable growth temperature is 12–24 °C [ 9 ]. Water dropwort has usually been cultivated by deep-water cultivation, shallow-water cultivation, shading cultivation and other cultivation methods [ 9 , 10 ]. Our previous research has found that shading cultivation was used to improve the flavor in the production of water dropwort [ 9 ].…”

“…Water dropwort has usually been cultivated by deep-water cultivation, shallow-water cultivation, shading cultivation and other cultivation methods [ 9 , 10 ]. Our previous research has found that shading cultivation was used to improve the flavor in the production of water dropwort [ 9 ]. Water dropwort has less pests and diseases, strong adaptability and is widely cultivated in the world [ 8 , 10 , 11 , 12 ].…”