CsATG101 Delays Growth and Accelerates Senescence Response to Low Nitrogen Stress in Arabidopsis thaliana

Wei Huang; Danni Ma; Xulei Hao; Jia Li; Li Xia; E Zhang; Pu Wang; Mingle Wang; Fei Guo; Yu Wang; Dejiang Ni; Hua Zhao

doi:10.3389/fpls.2022.880095

CsATG101 Delays Growth and Accelerates Senescence Response to Low Nitrogen Stress in Arabidopsis thaliana

Front Plant Sci. 2022 May 10:13:880095. doi: 10.3389/fpls.2022.880095. eCollection 2022.

Authors

Wei Huang^{1

2}, Danni Ma^{1

2}, Xulei Hao^{1

2}, Jia Li^{1

2}, Li Xia^{1

2}, E Zhang^{1

2}, Pu Wang^{1

2}, Mingle Wang^{1

2}, Fei Guo^{1

2}, Yu Wang^{1

2}, Dejiang Ni^{1

2}, Hua Zhao^{1

2}

Affiliations

¹ Key Laboratory of Horticultural Plant Biology of Ministry of Education, Huazhong Agricultural University, Wuhan, China.
² College of Horticulture and Forestry Sciences, Huazhong Agricultural University, Wuhan, China.

Abstract

For tea plants, nitrogen (N) is a foundational element and large quantities of N are required during periods of roundly vigorous growth. However, the fluctuation of N in the tea garden could not always meet the dynamic demand of the tea plants. Autophagy, an intracellular degradation process for materials recycling in eukaryotes, plays an important role in nutrient remobilization upon stressful conditions and leaf senescence. Studies have proven that numerous autophagy-related genes (ATGs) are involved in N utilization efficiency in Arabidopsis thaliana and other species. Here, we identified an ATG gene, CsATG101, and characterized the potential functions in response to N in A. thaliana. The expression patterns of CsATG101 in four categories of aging gradient leaves among 24 tea cultivars indicated that autophagy mainly occurred in mature leaves at a relatively high level. Further, the in planta heterologous expression of CsATG101 in A. thaliana was employed to investigate the response of CsATG101 to low N stress. The results illustrated a delayed transition from vegetative to reproductive growth under normal N conditions, while premature senescence under N deficient conditions in transgenic plants vs. the wild type. The expression profiles of 12 AtATGs confirmed the autophagy process, especially in mature leaves of transgenic plants. Also, the relatively high expression levels for AtAAP1, AtLHT1, AtGLN1;1, and AtNIA1 in mature leaves illustrated that the mature leaves act as the source leaves in transgenic plants. Altogether, the findings demonstrated that CsATG101 is a candidate gene for improving annual fresh tea leaves yield under both deficient and sufficient N conditions via the autophagy process.

Keywords: CsATG101; autophagy; nitrogen deficiency; senescence; tea plant.