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Schijlen, E. G. W. M.

Publications and source records attributed to Schijlen, E. G. W. M..

2 recordsLinked to original sources

Two high-quality rose genomes underpin a novel Rosa pangenome to advance rose genomics, phylogenetics, and breeding

Rosa, belonging to the family Rosaceae, encompasses more than 150 species which are widely distributed in the northern hemisphere. Renowned for their beauty, roses are cultivated throughout the world for ornamental purposes and the production of essential oils and perfumes. Despite their cultural and commercial significance, the genomic resources of wild Rosa species have not been studied comprehensively, hampering the understanding of their genetic diversity, evolutionary history, and breeding potential. Here we report on high-quality de novo genomes for Rosa sericea and Rosa rugosa. By integrating these two de novo genomes with existing public genomic resources, we have built a Rosaceae panproteome and a Rosa pangenome (spanning wild, traditional garden, and modern rose lineages) using a De Bruijn graph (DBG)-based approach. A maximum likelihood (ML) phylogeny of 18 Rosa haplotypes based on 4,367 single-copy core homology groups (genes) provided robust evolutionary inference, confirming the basal position of R. sericea, and enabled a gene-based macrosynteny analysis across the pangenome. Our analyses revealed significant genomic diversity among species, extensive variation in core gene content, and lineage-specific transposable element (TE) expansion patterns that contribute to the variation in Rosa genome size and to species-specific adaptations. The pangenome also revealed biased diversification of homology groups potentially linked to phenotypic plasticity in Rosa. Specifically, our analysis of the rose scent-related gene family, NUDX1, uncovered its evolutionary trajectory in Rosa, in which TEs insertions provided putative novel regulatory elements that facilitated adaptive evolution in metabolic pathways. This pangenomic study deepens our understanding of the genetic diversity and evolution of traits within the Rosa genus. In addition, the findings lay the foundation for future efforts to understand the genetic mechanisms driving trait evolution, which can support rose breeding.

genomics↗

The genome of Gynandropsis gynandra provides insights into whole-genome duplications and the evolution of C4 photosynthesis in Cleomaceae

Gynandropsis gynandra (Cleomaceae) is a cosmopolitan leafy vegetable and medicinal plant, which has also been used as a model to study C4 photosynthesis due to its evolutionary proximity to Arabidopsis. Here, we present a high-quality genome sequence of G. gynandra, anchored onto 17 main super- scaffolds with a total length of 740 Mb, an N50 of 42 Mb and 30,933 well-supported gene models. The G. gynandra genome and previously released genomes of C3 relatives in the Cleomaceae and Brassicaceae make an excellent model for studying the role of genome evolution in the transition from C3 to C4 photosynthesis. We revealed that G. gynandra and its C3 relative Tarenaya hassleriana shared a whole-genome duplication event (Gg-), then an addition of a third genome (Th-, +1x) took place in T. hassleriana but not in G. gynandra. Analysis of syntenic copy number of C4 photosynthesis-related gene families indicates that G. gynandra generally retained more duplicated copies of these genes than C3 T. hassleriana, and also that the G. gynandra C4 genes might have been under positive selection pressure. Both whole-genome and single-gene duplication were found to contribute to the expansion of the aforementioned gene families in G. gynandra. Collectively, this study enhances our understanding of the impact of gene duplication and gene retention on the evolution of C4 photosynthesis in Cleomaceae.

plant biology↗