Cloning and functional analysis of a Rice NLR Immune receptor pair- RPR (Rice Paired Receptor) 1&2

Abstract

The intracellular nucleotide-binding leucine-rich repeat (NLR) immune receptors of plants often work in pairs to percieve pathogen effectors and innitiate immunity reponses. In this article, we focused on gene cloning and functional analysis of NLR paired protein RPR1 and RPR2 from Oryza sativa Japonica. This pair of NLR , which was obtained through bioinformatic analysis, shared high similairy with the previously reported pair of RPS4/RRS1 from Arabidopsis. Both RPR1 and RPR2 consisted Coiled-Coil domain at the N- terminal, while WRKY domains only appeared at the C- terminal of RPR2. By using Golden Gate cloning strategy, constructs of RPR1 and RPR2 for Level -1, Level 0, Level 1 were obtained. The subcellular localization pattern of RPR1&2 was analyzed by doing transient expression, and confocal imaging result indicated that this NLR pair localized within cell nucleus. RPR1 and RPR2 functioned together to recognize effector PopP2, which triggered HR- like response of chlorosis symptoms shown within co-infiltrated region.