Comparative genome study identifies candidate genomic correlates of invasiveness in three cucurbit species

A comparative genomic study reported chromosome-scale assemblies for three invasive cucurbit species and identified genomic features that may be associated with their invasiveness. The research abstract describes recent proliferation of long terminal repeat retrotransposons, a lineage-specific whole-genome duplication in the tribe Sicyoeae, and expansions of gene families in pathways related to stress response, metabolism and secondary metabolite biosynthesis. The authors state that these features may collectively contribute to traits plausibly linked to competitive success, but functional validation is required.

The researchers used an integrated sequencing strategy combining PacBio HiFi sequencing, Illumina short reads and Hi-C technology. They generated chromosome-scale assemblies for Sicyos angulatus, Echinocystis lobata and Melothria pendula, with total genome sizes of 597.41 megabases, 629.27 megabases and 276.42 megabases, respectively. Scaffold N50 values were 50.69 Mb, 32.59 Mb and 22.38 Mb, while BUSCO completeness scores exceeded 98% for all three assemblies.

Comparative analysis encompassing 26 Cucurbitaceae species showed that lineage-specific dynamics of long terminal repeat retrotransposons were the primary correlate of genome-size variation. The researchers report that most insertion events occurred within the past two million years. They also detected a whole-genome duplication event confined to the tribe Sicyoeae, supported by markedly younger Ks peaks in S. angulatus and E. lobata.

Gene-family analysis identified different lineage-specific expansions in the three species: signal transduction and stress-response genes in S. angulatus, carbohydrate-metabolism and protein-synthesis components in E. lobata, and secondary-metabolite biosynthesis pathways in M. pendula. These are genomic associations rather than demonstrated causes of invasive behavior. The available abstract does not provide functional experiments establishing that the expanded gene families or other genomic features confer invasiveness traits, and it explicitly calls for functional validation.

Subject of Research: Comparative genomics of three invasive Cucurbitaceae species

Article Title: Chromosome-level genomes of three invasive Cucurbitaceae species provide insights into genomic features associated with invasiveness

Article References: Zhang, Y., Fu, W., Yuan, Z., Sun, C., Song, Z., Wang, Z., & Zhang, G. (2026). Chromosome-level genomes of three invasive Cucurbitaceae species provide insights into genomic features associated with invasiveness. BMC Plant Biology. https://doi.org/10.1186/s12870-026-09750-w

Image Credits: AI Generated

DOI: 10.1186/s12870-026-09750-w

Keywords: Cucurbitaceae, plant invasiveness, chromosome-level genomes, retrotransposons, whole-genome duplication, gene-family evolution, comparative genomics, genome assembly, Chromosome-level, genomes, three, invasive