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Updated: May 20, 2026

Induction of Adhesion-dependent Signals Using Low-intensity Ultrasound
Published on: May 8, 2012
Selective integrin subunit reduction disrupts fibronectin extracellular matrix deposition and fibrillin 1 gene
Rajeev K Boregowda1, Brooke M Krovic, Timothy M Ritty
1Division of Musculoskeletal Sciences, Department of Orthopaedics, Penn State College of Medicine, Hershey, PA 17033, USA. rajeev04mys@yahoo.com
Abstract:
Integrins are transmembrane receptors that can specifically bind extracellular matrix (ECM) proteins. Assembly of the ECM protein fibronectin into fibrils has been shown to be a cell-mediated process that requires integrins. Like fibronectin, fibrillin 1 is an ECM glycoprotein that can assemble into fibrils, but the role of integrins in fibril formation is not understood. To investigate the role of integrins in fibrillin 1 ECM deposition, cells that normally produce and assemble fibrillin 1 fibers in vitro were stably transfected with plasmid constructs encoding short interfering RNAs that target specific integrin subunits. Cells that were deficient in α2- and β3-integrin subunits produced and deposited fibronectin normally, but cells that were deficient for α5 and αV were unable to elaborate a fibronectin matrix, although they continued to produce and secrete the protein. Surprisingly, the cells that were unable to elaborate a fibronectin matrix also lost fibrillin 1 gene expression.
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