Searching for plant NLR immune receptors conferring resistance to potyviruses

To fight against invasion by pathogens, plants have evolved an elaborate innate immune system, of which the nucleotide-binding domain leucine-rich repeat-containing receptor (NLR) acts as the sensor and immune executor. Potyviruses, comprising one of the largest genera of plant viruses, cause severe crop yield losses worldwide. Inherited crop resistance to potyviruses can be used in breeding and plant transgenesis to control disease development. This review summarizes achievements in mapping and cloning NLR genes conferring dominant resistance against potyvirus in the families Fabaceae, Solanaceae, Brassicaceae, and Cucurbitaceae. It compares mechanisms of potyviral protein recognition and downstream signaling employed by NLRs and discusses strategies for exploiting NLRs to better control diseases caused by potyviruses.