Project description:<p><strong>BACKGROUND:</strong> Plants exhibit wide chemical diversity due to the production of specialized metabolites that function as pollinator attractants, defensive compounds, and signaling molecules. Lamiaceae (mints) are known for their chemodiversity and have been cultivated for use as culinary herbs, as well as sources of insect repellents, health-promoting compounds, and fragrance.</p><p><strong>FINDINGS:</strong> We report the chromosome-scale genome assembly of Callicarpa americana L. (American beautyberry), a species within the early-diverging Callicarpoideae clade of Lamiaceae, known for its metallic purple fruits and use as an insect repellent due to its production of terpenoids. Using long-read sequencing and Hi-C scaffolding, we generated a 506.1-Mb assembly spanning 17 pseudomolecules with N50 contig and N50 scaffold sizes of 7.5 and 29.0 Mb, respectively. In all, 32,164 genes were annotated, including 53 candidate terpene synthases and 47 putative clusters of specialized metabolite biosynthetic pathways. Our analyses revealed 3 putative whole-genome duplication events, which, together with local tandem duplications, contributed to gene family expansion of terpene synthases. Kolavenyl diphosphate is a gateway to many of the bioactive terpenoids in C. americana; experimental validation confirmed that CamTPS2 encodes kolavenyl diphosphate synthase. Syntenic analyses with Tectona grandis L. f. (teak), a member of the Tectonoideae clade of Lamiaceae known for exceptionally strong wood resistant to insects, revealed 963 collinear blocks and 21,297 C. americana syntelogs.</p><p><strong>CONCLUSIONS:</strong> Access to the C. americana genome provides a road map for rapid discovery of genes encoding plant-derived agrichemicals and a key resource for understanding the evolution of chemical diversity in Lamiaceae.</p>
Project description:itis vinifera cv. Tannat is largely cultivated in Uruguay for the production of high quality red wines. Its most notable characteristic is an elevated content of polyphenolic compounds, which provide an intense purple color and remarkable antioxidant properties to the wine. To characterize the genetic components encoding this important phenotypic characteristic, the genome of the Uruguayan Tannat clone UY11 was sequenced to 134X coverage using the Illumina technology and assembled with a mixed approach of de novo assembly and iterative mapping on the PN40024 reference genome. An approach based on both reference-guided annotation and de novo transcript assembly of RNA-Seq data allowed the definition of 3,673 genes not previously annotated in PN40024 that we consider novel, and the discovery of 2,228 genes not shared with the grapevine reference genome that we consider private to Tannat. Expression analysis showed that private genes contributed substantially (more than 50%) to the overall expression of enzymes involved in phenol and polyphenol biosynthesis indicating that the dispensable portion of the grapevine genome contains many private genes which are likely to contribute to the peculiar phenotypic characteristics of this grapevine variety.