Transcriptomic analysis of Salvia miltiorrhiza hairy roots in response to smoke-isolated karrikinolide (KAR1) using RNA-seq

The effect of karrikinolide (KAR1) on the salvianolic acid biosynthesis in hairy roots of Salvia miltiorrhiza has been studied by applying transcriptomics technology. Application of Illumina RNA-seq provides insights into the transcriptome profiles 0, 24 and 48 h after treatment with KAR1. The transcriptome was assembled with Trinity software, producing 138,993 unigenes with an average length of 1711 bp and an N50 value of 2523 bp. These included generous secondary metabolite biosynthesis and genes defense-related. Our investigations indicated significant differences in the responses of S. miltiorrhiza to KAR1 treatment. A total of 9411 and 9406 significant differentially expressed genes (DEGs) were respectively identified by treatment with KAR1 at 24 and 48 h. Among these DEGs, 865 DEGs (24 h) and 596 DEGs (48 h) were respectively classified into KEGG pathways. The result indicated that a significant number of these DEGs were enriched in phenylpropanoid biosynthesis. The expression of most glycosylsis-, glycosyltransferase-related genes were largely induced by KAR1. Furthermore, the genes that participated in biosynthesis of salvianolic acids were up-regulated after KAR1 treatment, including 4-coumaric acid CoA-ligase (4CL, 2 genes), phenylalanine ammonialyase (PAL, 3 genes), tyrosine aminotransferase (TAT, 5 genes), 4-hydroxyphenylpyruvate reductase (HPPR, 7 genes), rosmarinic acid synthase (RAS, 18 genes) and cinnamic acid 4-hydroxylase (C4H, 24 genes). The results revealed that genes related to the salvianolic acid biosynthesis were regulated by KAR1 in S. miltiorrhiza hairy roots. The findings provide insights into the molecular mechanism of salvianolic acid biosynthesis and a reference for the genetics research of S. miltiorrhiza next. (c) 2022 SAAB. Published by Elsevier B.V. All rights reserved.