Ectopic Expression of Jatropha curcas JcTAW1 Improves the Vegetative Growth, Yield, and Drought Resistance of Tobacco

Abstract

Abstract Jatropha curcas is a promising alternative bio-energy resource. However, underrun limited its broad application in the industry. Luckily, TAW1 is a high-productivity promoting gene that increases the lateral branches by prolonging the identification of inflorescence meristems to generate more spikes and flowers. In the current study, we introduced the Jatropha JcTAW1 gene into tobacco to depict a complete functional profile of the JcTAW1. Ectopic expressed JcTAW1 increased the lateral branches and ultimate yield of the transgenic tobacco plants. Moreover, the JcTAW1 lines observed a significantly higher plant height, longer roots, and better drought resistance. We performed RNA sequencing and weighted gene co-expression network analysis to determine which biological processes are affected by aberrant mutations in JCTAW1. We conclude that two up-regulated genes affect glucose metabolism and cell wall biosynthesis, and five down-regulated genes are involved in the negative regulation of DNA repair and TOR signaling. Biological processes such as carbon metabolism, cell wall biosynthesis, and ionization transport strongly affect the abnormal expression of JCTAW1. These findings indicate that JcTAW1 might drive the energy stream flowing to boost growth in three ways: (1) directly strengthening the energy metabolism cell proliferation; (2) improving the nutrient status by enhancing ion transport processes and releasing the TOR pathway from the negative regulation; (3) suppressing the DNA repair system to facilitate the cell proliferation.