bioRxiv preprint doi: https://doi.org/10.1101/704403; this version posted July 17, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. C6orf203 controls OXPHOS function through modulation of mitochondrial protein biosynthesis number of characters excluding Materials and Methods: 40,651 Sara Palacios-Zambrano1,2, Luis Vázquez-Fonseca1,2, Cristina González-Páramos1,2, Laura Mamblona1,2, Laura Sánchez-Caballero3, Leo Nijtmans3, Rafael Garesse1,2 and Miguel Angel Fernández-Moreno1,2,* 1 Departamento de Bioquímica, Instituto de Investigaciones Biomédicas “Alberto Sols” UAM CSIC and Centro de Investigación Biomédica en Red en Enfermedades Raras (CIBERER). Facultad de Medicina, Universidad Autónoma de Madrid. Madrid 28029, Spain. 2 Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Madrid 28041, Spain. 3 Department of Pediatrics, Radboud Center for Mitochondrial Medicine, Radboud University Medical Center, Nijmegen, The Netherlands. * To whom correspondence should be addressed. Tel:+34 91 497 31 29; Email:
[email protected] Running title “C6orf203 controls mt-proteins synthesis” bioRxiv preprint doi: https://doi.org/10.1101/704403; this version posted July 17, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder. All rights reserved. No reuse allowed without permission. ABSTRACT Mitochondria are essential organelles present in the vast majority of eukaryotic cells. Their central function is to produce cellular energy through the OXPHOS system, and functional alterations provoke so-called mitochondrial OXPHOS diseases. It is estimated that several hundred mitochondrial proteins have unknown functions. Very recently, C6orf203 was described to participate in mitochondrial transcription under induced mitochondrial DNA depletion stress conditions.