Genome-Wide Identification of CsATGs in Tea Plant and the Involvement of CsATG8e in Nitrogen Utilization

Nitrogen (N) is a macroelement with an indispensable role in the growth and development of plants, and tea plant ( ) is an evergreen perennial woody species with young shoots for harvest. During senescence or upon N stress, autophagy has been shown to be induced in leaves, involving a variety of autophagy-related genes ( ), which have not been characterized in tea plant yet. In this study, a genome-wide survey in tea plant genome identified a total of 80 autophagy-related genes, The expression of in the tea plant showed an obvious increase from S1 (stage 1) to S4 (stage 4), especially for . The expression levels of ( ) and genes involved in N transport and assimilation were greatly improved in overexpressed . Compared with wild type, the overexpression plants showed earlier bolting, an increase in amino N content, as well as a decrease in biomass and the levels of N, phosphorus and potassium. However, the N level was found significantly higher in APER (aerial part excluding rosette) in the overexpression plants relative to wild type. All these results demonstrated a convincing function of in N remobilization and plant development, indicating as a potential gene for modifying plant nutrient utilization.