Loss of Nardilysin, a Mitochondrial Co-chaperone for α-Ketoglutarate Dehydrogenase, Promotes mTORC1 Activation and Neurodegeneration.

Neuron 2017 Jan 04

filter terms:

We previously identified mutations in Nardilysin (dNrd1) in a forward genetic screen designed to isolate genes whose loss causes neurodegeneration in Drosophila photoreceptor neurons. Here we show that NRD1 is localized to mitochondria, where it recruits mitochondrial chaperones and assists in the folding of α-ketoglutarate dehydrogenase (OGDH), a rate-limiting enzyme in the Krebs cycle. Loss of Nrd1 or Ogdh leads to an increase in α-ketoglutarate, a substrate for OGDH, which in turn leads to mTORC1 activation and a subsequent reduction in autophagy. Inhibition of mTOR activity by rapamycin or partially restoring autophagy delays neurodegeneration in dNrd1 mutant flies. In summary, this study reveals a novel role for NRD1 as a mitochondrial co-chaperone for OGDH and provides a mechanistic link between mitochondrial metabolic dysfunction, mTORC1 signaling, and impaired autophagy in neurodegeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

Citation

Wan Hee Yoon, Hector Sandoval, Sonal Nagarkar-Jaiswal, Manish Jaiswal, Shinya Yamamoto, Nele A Haelterman, Nagireddy Putluri, Vasanta Putluri, Arun Sreekumar, Tulay Tos, Ayse Aksoy, Taraka Donti, Brett H Graham, Mikiko Ohno, Eiichiro Nishi, Jill Hunter, Donna M Muzny, Jason Carmichael, Joseph Shen, Valerie A Arboleda, Stanley F Nelson, Michael F Wangler, Ender Karaca, James R Lupski, Hugo J Bellen. Loss of Nardilysin, a Mitochondrial Co-chaperone for α-Ketoglutarate Dehydrogenase, Promotes mTORC1 Activation and Neurodegeneration. Neuron. 2017 Jan 04;93(1):115-131