Knockdown of MLC1 in primary astrocytes causes cell vacuolation: A MLC disease cell model

Neurobiology of Disease

Miguel Lopez de Heredia¹  Chun-Fu Lien¹  Margreet C. Ridder²  Xavier Capdevila-Nortes³  Raúl Estévez⁴  Albee Messing⁵  Marjo S. van der Knaap⁵  Tania López-Hernández⁵  Virginia Nunes⁶  Dariusz C. Gorecki⁶  Ilja Boor⁷  Tracy Hagemann⁷  Anna Duarri⁷  Marisol Montolio⁷  Gert C. Scheper⁸  Albert Martínez⁸ 

[1] Centro de Investigación en Red de Enfermedades Raras (CIBERER), U-750, Spain;Laboratorio de Genética Molecular-IDIBELL, Spain;Centro de Investigación en Red de Enfermedades Raras (CIBERER), U-730, ISCIII, Spain;Department of Cell Biology, Faculty of Biology and Institute for Research in Biomedicine (IRB), Spain;Department of Pediatrics/Child Neurology, VU University Medical Center, Amsterdam, the Netherlands;Institute of Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, UK;Sección de Fisiología, Departamento de Ciencias Fisiológicas II, Universidad de Barcelona, Spain;University of Wisconsin-Madison, WI, USA;

关键词: Astrocyte;    Junctions;    Leukodystrophy;    Volume;   

DOI  :  

来源: DOAJ

【 摘 要 】

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare type of leukodystrophy, in the majority of cases caused by mutations in the MLC1 gene. MRI from MLC patients shows diffuse cerebral white matter signal abnormality and swelling, with evidence of increased water content. Histopathology in a MLC patient shows vacuolation of myelin, which causes the cerebral white matter swelling. MLC1 protein is expressed in astrocytic processes that are part of blood- and cerebrospinal fluid-brain barriers. We aimed to create an astrocyte cell model of MLC disease. The characterization of rat astrocyte cultures revealed MLC1 localization in cell–cell contacts, which contains other proteins described typically in tight and adherent junctions. MLC1 localization in these contacts was demonstrated to depend on the actin cytoskeleton; it was not altered when disrupting the microtubule or the GFAP networks. In human tissues, MLC1 and the protein Zonula Occludens 1 (ZO-1), which is linked to the actin cytoskeleton, co-localized by EM immunostaining and were specifically co-immunoprecipitated. To create an MLC cell model, knockdown of MLC1 in primary astrocytes was performed. Reduction of MLC1 expression resulted in the appearance of intracellular vacuoles. This vacuolation was reversed by the co-expression of human MLC1. Re-examination of a human brain biopsy from an MLC patient revealed that vacuoles were also consistently present in astrocytic processes. Thus, vacuolation of astrocytes is also a hallmark of MLC disease.

【 授权许可】

Unknown