Telomere-to-telomere, gap-free genome of mung bean (Vigna radiata) provides insights into domestication under structural variation

Abstract

Mung bean (Vigna radiata), an essential annual legume, holds substantial value in global agriculture due to its short growth cycle, low input requirements, and nutritional benefits. Despite extensive domestication, the genetic mechanisms underlying its morphological and physiological evolution remain incompletely understood. In this study, we present a gap-free, telomere-to-telomere genome assembly of the mung bean cultivar 'Weilv-9', achieved through the integration of PacBio HiFi, Oxford Nanopore, and Hi-C sequencing technologies. The 500 Mb assembly, encompassing 11 chromosomes and containing 28,740 protein-coding genes, reveals that 49.17% of the genome comprises repetitive sequences. Within the genome, we found the recent amplification of transposable elements significantly impacts the expression of nearby genes. Furthermore, integrating structural variation and SNP data from resequencing, we identified that the fatty acid synthesis, suberin biosynthetic, and phenylpropanoid metabolic processes have undergone strong selection during domestication. These findings provide valuable insights into the genetic mechanisms driving domestication and offer a foundation for future genetic enhancement and breeding programs in mung beans and related species.