tailieunhanh - Báo cáo khoa học: Biomechanical properties of native basement membranes

Basement membranes are sheets of extracellular matrix that separate epi-thelia from connective tissues and outline muscle fibers and the endothelial lining of blood vessels. A major function of basement membranes is to establish and maintain stable tissue borders, exemplified by frequent vascu-lar breaks and a disrupted pial and retinal surface in mice with mutations or deletions of basement membrane proteins. | ỊFEBS Journal Biomechanical properties of native basement membranes Joseph Candiello1 Manimalha Balasubramani2 Emmanuel M. Schreiber2 Gregory J. Cole3 Ulrike Mayer4 Willi Halfter5 and Hai Lin1 1 Department of Bioengineering University of Pittsburgh PA USA 2 Genomics and Proteomics Core Laboratory University of Pittsburgh PA USA 3 Julius L. Chambers Biomedical Biotechnology Research Institute North Carolina CentralUniversity Durham NC USA 4 BiomedicalResearch Centre Schoolof BiologicalSciences University of East Anglia Norwich UK 5 Department of Neurobiology University of Pittsburgh PA USA Keywords atomic force microscopy basallamina basement membrane extracellular matrix eye development Correspondence W. Halfter Department of Neurobiology University of Pittsburgh Pittsburgh PA 15262 USA Fax 1 412 648 1441 Tel 1 412 648 9424 E-mail whalfter@ Received 14 December 2006 revised 14 February 2007 accepted 5 April 2007 doi Basement membranes are sheets of extracellular matrix that separate epithelia from connective tissues and outline muscle fibers and the endothelial lining of blood vessels. A major function of basement membranes is to establish and maintain stable tissue borders exemplified by frequent vascular breaks and a disrupted pial and retinal surface in mice with mutations or deletions of basement membrane proteins. To directly measure the biomechanical properties of basement membranes chick and mouse inner limiting membranes were examined by atomic force microscopy. The inner limiting membrane is located at the retinal-vitreal junction and its weakening due to basement membrane protein mutations leads to inner limiting membrane rupture and the invasion of retinal cells into the vitreous. Transmission electron microscopy and western blotting has shown that the inner limiting membrane has an ultrastructure and a protein composition typical for most other basement membranes and thus provides a suitable model for determining