Project description:During the over 300 million years of co-evolution between herbivorous insects and their host plants, a dynamic equilibrium of evolutionary arms race has been established. However, the co-adaptation between insects and their host plants is a complex process, often driven by multiple evolutionary mechanisms. We found that various lepidopteran pests that use maize as a host exhibit differential adaptation to the plant secondary metabolites, benzoxazinoids (BXs). Notably, the Spodoptera genus, including Spodoptera frugiperda (fall armyworm) and Spodoptera litura (cotton leafworm), demonstrate greater tolerance to BXs compared to other insects. Through comparative transcriptomic analysis of the midgut, we identified four candidate genes potentially involved in BXs detoxification in S. frugiperda. Subsequently, we confirmed two UGT genes, Sfru33T10 and Sfru33F32, as key players in BXs detoxification using CRISPR/Cas9 gene-editing technology. Phylogenetic analysis revealed that Sfru33T10 evolved independently within the Noctuidae family and is involved in the glycosylation of HDMBOA, while Sfru33F32 evolved independently within the Spodoptera genus and functions as a key detoxification enzyme responsible for the glycosylation of both DIMBOA and HMBOA. Our study demonstrates that the UGT gene family plays a crucial role in the adaptation of noctuid insects to maize, with multiple independent evolutionary events within the Noctuidae family and the Spodoptera genus contributing significantly to host adaptation.
Project description:The Zygnematophyceae are the closest algal relatives of land plants and hence interesting to understand land plant evolution. Species of the genus Serritaenia have an aerophytic lifestyle and form colorful, mucilaginous capsules, which surround the cells and block harmful solar radiation. Under laboratory conditions the production of this “sunscreen mucilage” can be induced by ultraviolet B radiation. The present dataset reveals insights into the cellular reaction of this alga to UV radiation (a major stressor in terrestrial habitats) and allows for comparisons with other algae and land plants to draw evolutionary conclusions.
Project description:Organisms specialized to extreme environments can be the product of millions of years of evolutionary engineering and refinement. The underlying genetics can be quite distinct from those operating at earlier stages of trait innovation. In this work, we have developed the multistress-resistant yeast Kluyveromyces marxianus, which diverged from its closest relative >20 million years ago, as a model for interspecies comparative biology and genomics. In growth assays of the Kluyveromyces genus, we found that K. marxianus exhibited unique tolerance of high heat and a subset of chemical stress conditions. We then generated and analyzed omic profiles from across the genus to find molecular features associated with—and potentially causal for—K. marxianus traits. Expression profiling revealed divergent lipid processing and membrane transport programs in K. marxianus, borne out in changes in lipid utilization in experimental assays. Sequence analyses found robust evidence for expansions in gene families in the K. marxianus genome, most notably among transmembrane transporters and in metabolic enzymes. In molecular-evolution tests, we identified adaptive protein variants throughout the K. marxianus genome, among which plasma membrane transporters were over-represented. These data enable a model of the molecular mechanisms and evolutionary pressures underlying K. marxianus traits, including adaptive changes to transporters, lipid processing, and membrane functions mediating stress resistance.