The RagA GTPase protects young egg chambers in Drosophila
Ying Zhou,
Jianwen Guan,
Guoqiang Meng,
Weikang Fan,
Churui Ge,
Chunmei Niu,
Yang Cheng,
Yuanyuan Fu,
Yingying Lu,
Youheng Wei
Affiliations
Ying Zhou
Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
Jianwen Guan
Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
Guoqiang Meng
Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
Weikang Fan
Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
Churui Ge
Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
Chunmei Niu
Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
Yang Cheng
Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
Yuanyuan Fu
Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
Yingying Lu
College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China
Youheng Wei
Joint International Research Laboratory of Agriculture and Agri-Product Safety, the Ministry of Education of China, Yangzhou University, Yangzhou 225009, China; College of Bioscience and Biotechnology, Yangzhou University, Yangzhou 225009, China; Institute of Reproduction and Metabolism, Yangzhou University, Yangzhou 225009, China; Corresponding author
Summary: The preservation of female fertility under unfavorable conditions is essential for animal reproduction. Inhibition of the target of rapamycin complex 1 (TORC1) is indispensable for Drosophila young egg chamber maintenance under nutrient starvation. Here, we show that knockdown of RagA results in young egg chamber death independent of TORC1 hyperactivity. RagA RNAi ovaries have autolysosomal acidification and degradation defects, which make the young egg chambers sensitive to autophagosome augmentation. Meanwhile, RagA RNAi ovaries have nuclear-localized Mitf, which promotes autophagic degradation and protects young egg chambers under stress. Interestingly, GDP-bound RagA rescues autolysosome defects, while GTP-bound RagA rescues Mitf nuclear localization in RagA RNAi young egg chambers. Moreover, Rag GTPase activity, rather than TORC1 activity, controls Mitf cellular localization in the Drosophila germ line. Our work suggests that RagA separately controls autolysosomal acidification and Mitf activity in the Drosophila young egg chambers.
