CT2 is involved in yield-related traits and cell proliferation of maize.

Heterotrimeric G-proteins are multifunctional modulators that participate in a wide range of growth and developmental processes in eukaryotic species, including yeast, plants, and animals. In this study, we characterized a maize mutant, ct2, that showed a compact architecture and reproductive-organ-related phenotypic variation. Heredity analysis indicated that the mutant phenotypes resulted from monogenic inheritance. The target gene, CT2, was cloned using bulked segregant analysis and map-based cloning. Sequence alignment showed that the ct2 mutation was the result of a 185-bp sequence insertion at the 3' terminal of CT2. Protein structure prediction and phylogenetic analysis indicated that CT2 is a canonical Gɑ of monocotyledonous plants. Through phenotypic identification, we found that CT2 was involved in yield-related traits in maize. Furthermore, our findings indicated that CT2 promotes cell proliferation in stem internodes, which may result from the upregulation of zeatin biosynthesis by CT2. This research provides direction for further studies in the biological function of CT2 in cell proliferation and in yield-related traits, which will be beneficial for maize breeding through screening and application of beneficial alleles.