Junping Gao: Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China.
Ying Wang: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, P. R. China.
Xinxi He: Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China.
Long Chen: Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China.
Shuaibin Wang: Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China.
Xinyao Zhang: Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China.
Sirui Zhu: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, P. R. China.
Xiaoxu Li: Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China.
Xiaonian Yang: Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China.
Wenxuan Pu: Technology Center, China Tobacco Hunan Industrial Co., Ltd., Changsha 410007, China.
Yuanyuan Li: State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Biology, and Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation, Hunan University, Changsha 410082, P. R. China.
The biochemical and transcriptional regulatory mechanisms of chlorophyll metabolism have been extensively studied, but the translational regulatory mechanisms remain poorly understood. In this study, we found that Nt DHS1 deficiency in N. tabacum resulted in smaller leaves and increased leaf chlorophyll content. Protein content determination experiments revealed that the global protein synthesis of the Ntdhs1 mutant was decreased. A ribosome profiling sequence (Ribo-seq) assay showed that the translation level of genes related to cell growth was significantly reduced, while the translation level of chlorophyll metabolism related genes was significantly increased in Ntdhs1 mutant. Biochemical analysis further demonstrated that Nt DHS interacts with the translation initiation factor Nt eIF5A. Moreover, the Nteif5a1 mutant exhibited phenotypes similar to the Ntdhs1 mutant, including a reduced translation level of cell growth related genes and increased translation level of chlorophyll metabolism related genes. Our studies suggest that the Nt DHS-Nt eIF5A complex regulates leaf senescence by modulating the translation of specific genes.
