| Description |
Houttuynia cordata Thunb, commonly known as yuxingcao in China, is named for its characteristic fishy smell and is widely recognized as an important herb and vegetable in many parts of Asia. However, the lack of genomic information on H. cordata limits the understanding of its population structure, genetic diversity and the biosynthesis of medicinal compounds. Here, we used single-molecule sequencing sequencing, llumina paired-end sequencing and chromosome conformation capture technology to construct the first chromosome-scale decaploid H. cordata reference genome. The genome assembly was 2.63 Gb in size with 1,348 contigs and a contig N50 of 21.94 Mb, which were further clustered and ordered into 88 pseudo-chromosomes based on Hi-C analysis. The results of genome evolution analysis showed that H. citrina had a whole-genome duplication (WGD) event about 17 million years ago, and an additional WGD event occurred in 3.3 million years ago, which may be the main factor leading to the number of multiple copies of orthologous genes are very abundant. Here, transcriptome sequencing across five different tissues revealed significant expansion and distinct expression patterns of key gene families, such as L-amino acid/L-tryptophan decarboxylase and strictosidine synthase, essential for the biosynthesis of isoquinoline and indole alkaloids, along with the identification of genes like TTM3, critical for root development. This study constructed the first decaploid medicinal plant genome, and revealed the genome evolution and polyploidisation events of H. cordata. |
