Genome-Wide Identification of in Tea Plant and the Involvement of 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.