ultrastructural modifications in the mitochondria of hypoxia-adapted drosophila melanogaster线粒体的超微结构修改hypoxia-adapted黑腹果蝇.pdf

Ultrastructural Modifications in the Mitochondria of Hypoxia-Adapted Drosophila melanogaster 1. 2 3 1 1 2 2 Guy Perkins , Yu-hsin Hsiao , Songyue Yin , Jonathan Tjong , My T. Tran , Jenna Lau , Jin Xue , 3 1 2 . Siqi Liu , Mark H. Ellisman , Dan Zhou * 1 National Center for Microscopy and Imaging Research, University of California San Diego, La Jolla, California, United States of America, 2 Department of Pediatrics, University of California San Diego, La Jolla, California, United States of America, 3 Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, P.R. China Abstract Chronic hypoxia (CH) occurs under certain physiological or pathological conditions, including in people who reside at high altitude or suffer chronic cardiovascular or pulmonary diseases. As mitochondria are the predominant oxygen-consuming organelles to generate ATP through oxidative phosphorylation in cells, their responses, through structural or molecular modifications, to limited oxygen supply play an important role in the overall functional adaptation to hypoxia. Here, we report the adaptive mitochondrial ultrastructural modifications and the functional impacts in a recently generated hypoxia- adapted Drosophila melanogaster strain that survives severe, otherwise lethal, hypoxic conditions. Using electron tomography, we discovered increased mitochondrial volume density and cristae abundance, yet also cristae fragmentation and a unique honeycomb-like structure in the mitochondria of hypoxia-adapted flies. The homeostatic levels of adenylate ¨