High-resolution genome mapping and functional dissection of chlorogenic acid production in Lonicera maackii

Abstract

Amur honeysuckle (Lonicera maackii) is a widely used medicinal plant of the Caprifoliaceae family that produces chlorogenic acid. Research on this plant mainly focuses on its ornamental value and medicinal compounds, but a reference genome sequence and molecular resources for accelerated breeding are currently lacking. Herein, Nanopore sequencing and high-throughput chromosome conformation capture (Hi-C) allowed a chromosome-level genome assembly of Lonicera maackii (2n = 18). A global view of the gene regulatory network involved in the biosynthesis of chlorogenic acid and the dynamics of fruit coloration in L. maackii was established through metabolite profiling and transcriptome analyses. Moreover, we identified the genes encoding hydroxycinnamoyl-CoA quinate transferase (LmHQT) and hydroxycinnamoyl-CoA shikimic/quinate transferase (LmHCT), which localized to the cytosol and nucleus. Heterologous overexpression of these genes in Nicotiana benthamiana leaves resulted in elevated chlorogenic acid contents. Importantly, HPLC analyses revealed that LmHCT and LmHQTs recombinant proteins modulate the accumulation of chlorogenic acid (CGA) using quinic acid and caffeoyl CoA as substrates, highlighting the importance of LmHQT and LmHCT in chlorogenic acid biosynthesis. These results confirmed that LmHQTs and LmHCT catalyze the biosynthesis of CGA in vitro. The genomic data presented in this study will offer a valuable resource for the elucidation of CGA biosynthesis and facilitating selective molecular breeding.

Uncovering the Role of Hydroxycinnamoyl Transferase in Boosting Chlorogenic Acid Accumulation in Carthamus tinctorius Cells under Methyl Jasmonate Elicitation

“…The subcellular localization analysis showed that the CtHCT-eGFP fusion gene produced significant green fluorescent signals in both the cytosol and nucleus of N. benthamiana (Figure 6E), in agreement with previous studies that have reported the cytoplasm as the main site of CGA biosynthesis [16]. Subsequently, transient overexpression of the CtHCT-eGFP fusion gene in N. benthamiana indicated a 41.56% increase in the relative CGAs (namely 5-caffeoyl quinic acid) content (Figure 6F,G).…”

“…The fusion construct was introduced into Agrobacterium tumefaciens GV3101 using the freeze-thaw method. Positive clones with kanamycin resistance were validated with PCR ( Table S2 ) and used for transient transformation in Nicotiana benthamiana ( N. benthamiana ) following previously reported methods [ 16 ]. On day 3 after transformation, the fluorescence signals of N. benthamiana in the experimental (35S:: CtHCT-eGFP ) and control groups (35S:: eGFP ) were observed under a confocal microscope (LSM 980, Carl Zeiss AG, Jena, Germany).…”

“…The biosynthesis pathway of CGAs has been investigated in various species, such as Cecropia obtusifolia , Lonicera maackii , Ipomoea batatas , and Echinacea purpurea [ 14 , 15 , 16 , 17 ]. However, due to the complexity of CGA biosynthesis, there is ongoing debate regarding their precise biosynthetic mechanisms [ 18 ].…”

Transcriptional Regulation of SugarCane Response to Sporisorium scitamineum: Insights from Time-Course Gene Coexpression and Ca2+ Signaling

“…scitamineum have been investigated by high-throughput sequencing, ,− but most of them focused mainly on the exploration of single genes or pathways, and relatively few studies were conducted on the regulatory relationships between TFs and various response mechanisms. In recent years, the TO-GCN, an effective way to elaborate gene regulatory networks, has been widely used in various plants. − Li et al applied the TO-GCN to analyze the gene regulatory networks of amur honeysuckle (Lonicera maackii) and revealed that the chlorogenic acid biosynthesis and anthocyanin metabolism pathways were responsible for the accumulation of red pigments. Zhao et al used time-course transcriptomics analysis and constructed multiple subnetworks to explore the poplar response to salt stress.…”

“…In recent years, the TO-GCN, an effective way to elaborate gene regulatory networks, has been widely used in various plants. 15−17 Li et al 42 applied the TO-GCN to analyze the gene regulatory networks of amur honeysuckle (Lonicera maackii) and revealed that the chlorogenic acid biosynthesis and anthocyanin metabolism pathways were responsible for the accumulation of red pigments. Zhao et al 16 used timecourse transcriptomics analysis and constructed multiple subnetworks to explore the poplar response to salt stress.…”