Map based cloning ofCT2and the pilot functional exploration in abiotic stress

Abstract

AbstractHeterotrimeric G-proteins are multifunctional modulators that participate in a wide range of growth and developmental processes in eukaryotic species, from yeast to plants and animals. Component detection and the study of G protein signaling in most plants, including maize, are in the initial stages. In this study, we characterized a maize mutant,ct2, that showed a compact architecture and reproductive organ-related phenotypic variation. The target geneCT2was cloned using bulked segregant analysis and map-based cloning. Gene structure prediction and phylogenetic analysis indicated thatCT2is a canonical Gα protein belonging to the monocotyledonous group. Promoter analysis ofCT2and RNA sequencing revealedcis-acting regulatory elements and differentially expressed genes involved in JA signaling and stress tolerance. The transcription ofCT2was repressed by NaCl and PEG treatments, andct2mutation in thect2line compromised stress tolerance in maize. On the basis of our results, we proposed a schema diagram ofCT2-regulated biological process and their feedback onCT2transcription. This research provides clues for further studies ofCT2function in hormone signaling and stress tolerance, which is beneficial for maize breeding through the screening and application of beneficial alleles.