Rab35-regulated lipid turnover by myotubularins represses mTORC1 activity and controls myelin growth

Linda Sawade, Federica Grandi, Marianna Mignanelli, Genaro Patiño-López, Kerstin Klinkert, Francina Langa-Vives, Roberta Di Guardo, Arnaud Echard, Alessandra Bolino, Volker Haucke

Research output: Contribution to journalArticlepeer-review

Abstract

Inherited peripheral neuropathies (IPNs) represent a broad group of disorders including Charcot-Marie-Tooth (CMT) neuropathies characterized by defects primarily arising in myelin, axons, or both. The molecular mechanisms by which mutations in nearly 100 identified IPN/CMT genes lead to neuropathies are poorly understood. Here we show that the Ras-related GTPase Rab35 controls myelin growth via complex formation with the myotubularin-related phosphatidylinositol (PI) 3-phosphatases MTMR13 and MTMR2, encoded by genes responsible for CMT-types 4B2 and B1 in humans, and found that it downregulates lipid-mediated mTORC1 activation, a pathway known to crucially regulate myelin biogenesis. Targeted disruption of Rab35 leads to hyperactivation of mTORC1 signaling caused by elevated levels of PI 3-phosphates and to focal hypermyelination in vivo. Pharmacological inhibition of phosphatidylinositol 3,5-bisphosphate synthesis or mTORC1 signaling ameliorates this phenotype. These findings reveal a crucial role for Rab35-regulated lipid turnover by myotubularins to repress mTORC1 activity and to control myelin growth.

Original languageEnglish
Article number2835
JournalNature Communications
Volume11
Issue number1
DOIs
Publication statusPublished - Dec 1 2020

ASJC Scopus subject areas

  • Chemistry(all)
  • Biochemistry, Genetics and Molecular Biology(all)
  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Rab35-regulated lipid turnover by myotubularins represses mTORC1 activity and controls myelin growth'. Together they form a unique fingerprint.

Cite this