In this week's Nature, a team of US and Chinese scientists describes using genome mining to identify a natural herbicide with a unique mechanism of action. By scanning the genomes of filamentous fungi — many of which make compounds that kill plants to aid in colonization — the scientists pinpointed a gene cluster involved in the production of aspterric acid, which inhibits an enzyme involved in the final step of a key biological pathway in plants. Further experimentation showed aspterric acid is an effective herbicide when delivered as a spray and that the gene cluster could confer resistance to the agent when transferred into plants. "Our discovery demonstrates the potential of using a resistance gene-directed approach in the discovery of bioactive natural products," the authors write.
Also in Nature, a multi-institute research group reports a CRISPR-based method for reprogramming human T cells that does not require the use of viral vectors. The approach allows for the rapid and efficient insertion of large DNA sequences at specific sites in the genomes of primary human T cells, and preserves cell viability and function. The investigators used the technique to correct a pathogenic mutation in cells from patients with a monogenic autoimmune disease, as well as to engineer T cells to selectively attack cancer cells. The findings show that non-viral genome editing can enable the therapeutic engineering of primary human immune cells, the researchers say.