The COG1-OsSERL2 complex senses cold to trigger signaling network for chilling tolerance in japonica rice

Improvement of chilling tolerance is a key strategy to face potential menace from abnormal temperature in rice production, which depends on the signaling network triggered by receptors. However, little is known about the QTL genes encoding membrane complexes for sensing cold. Here, Chilling-tolerance in Gengdao/japonica rice 1 (COG1) was isolated from a chromosome segment substitution line containing a QTL (qCS11-jap) for chilling sensitivity. The major gene COG1 was found to confer chilling tolerance in japonica rice. In natural rice populations, only the haplogroup1 encoded a functional COG1. Evolutionary analysis showed that COG1 originated from Chinese O. Rufipogon and was fixed in japonica rice during domestication. COG1, a membrane-localized LRR-RLP, targeted and activated the kinase OsSERL2 in a cold-induced manner, promoting chilling tolerance. Furthermore, the cold signal transmitted by COG1-OsSERL2 activates OsMAPK3 in the cytoplasm. Our findings reveal a cold-sensing complex, which mediates signaling network for the chilling defense in rice.