This article is direct evidence of MuLV integrating into Mitochondrial DNA. XMRV is a MuLV class virus . The second paper shows how integrated MuLV directly damages Mitochondrial DNA by altering the bases so they dont make sense anymore to the repair enzymes. Changing just three bases can reduce the energy output of a mitochondria by 60% cience 13 February 1976: Vol. 191. no. 4227, pp. 569 - 571 DOI: 10.1126/science.1251192 Prev | Table of Contents | Next Articles Science, Vol 191, Issue 4227, 569-571 Copyright 1976 by American Association for the Advancement of Science articles Proviral DNA of Moloney leukemia virus: purification and visualization AM Gianni, Hutton JR, D Smotkin, and RA Weinberg Closed-circular proviral DNA of Moloney leukemia virus has been purified from a 10(7) excess of cellular and mitochondrial DNA. The DNA can be visualized in the electron microscope and has the contour length of a molecule with a moleculecular weight of about 5.5 + 10(6). Electron microscopic observation of a hybrid between viral RNA and this circular DNA confirms the viral origin of this molecule. mitochondrial Mulv viral damage, in J. Neurosci. Search The Journal of Neuroscience, March 12, 2008, 28(11):2827-2836; doi:10.1523/JN MuLv damage of Mitochondria Neurobiology of Disease The Mitochondrial Protease AFG3L2 Is Essential for Axonal Development Francesca Maltecca,1 * Asadollah Aghaie,3 * David G. Schroeder,4 Laura Cassina,1 Benjamin A. Taylor,4 Sandra J. Phillips,4 Mariachiara Malaguti,2 Stefano Previtali,2 Jean-Louis Gunet,3 Angelo Quattrini,2 Gregory A. Cox,4 and Giorgio Casari1,5 1Human Molecular Genetics Unit, and 2Neuropathology Unit and Istituto di Neurologia Sperimentale, San Raffaele Scientific Institute, 20132 Milan, Italy, 3Departement de Biologie du Developpement, Institut Pasteur, 75724 Paris Cedex 15, France, 4The Jackson Laboratory, Bar Harbor, Maine 04609, and 5Vita-Salute San Raffaele University, School of Medicine, 20132 Milan, Italy Abstract Top Abstract Introduction The mitochondrial metalloprotease AFG3L2 assembles with the homologous protein paraplegin to form a supracomplex in charge of the essential protein quality control within mitochondria. Mutations of paraplegin cause a specific axonal degeneration of the upper motoneuron and, therefore, hereditary spastic paraplegia. Here we present two Afg3l2 murine models: a newly developed null and a spontaneous mutant that we found carrier of a missense mutation. Contrasting with the mild and late onset axonal degeneration of paraplegin-deficient mouse, Afg3l2 models display a marked impairment of axonal development with delayed myelination and poor axonal radial growth leading to lethality at P16. The increased severity of the Afg3l2 mutants is explained by two main molecular features that differentiate AFG3L2 from paraplegin: its higher neuronal expression and its versatile ability to support both hetero-oligomerization and homo-oligomerization. Our data assign to AFG3L2 a crucial role by linking mitochondrial metabolism and axonal development. Moreover, we propose AFG3L2 as an excellent candidate for motoneuron and cerebellar diseases with early onset unknown etiology.