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PubMed · 11973345

Integrin clustering induces kinectin accumulation.

Huan Tran·Roumen Pankov·Simon D Tran·Brian Hampton·Wilson H Burgess·Kenneth M Yamada
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Abstract

Integrin receptors mediate the formation of adhesion complexes and play important roles in signal transduction from the extracellular matrix. Integrin-based adhesion complexes (IAC) contain proteins that link integrins to the cytoskeleton and recruit signaling molecules, including vinculin, paxillin, focal adhesion kinase, talin and alpha-actinin. In this study, we describe a approximately 160 kDa protein that is markedly enriched at IAC induced by clustering integrins with fibronectin-coated beads. Protein sequence analysis reveals that this approximately 160 kDa protein is kinectin. Kinectin is an integral membrane protein found in endoplasmic reticulum, and it serves as a receptor for the motor protein kinesin. Fibronectin-induced IAC sequestered over half of the total cellular content of kinectin within 20 minutes. In addition, two other ER-resident proteins, RAP [low-density lipoprotein receptor-related protein (LRP) receptor-associated protein] and calreticulin, were found to be clustered at IAC, whereas kinesin was not. Our results identify a novel class of constituents of IAC.

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Amino Acid SequenceAnimalsCell Adhesion MoleculesCell LineChromatography, AffinityCytoskeletonEndoplasmic ReticulumFibroblastsFibronectinsHumansIntegrinsMacromolecular SubstancesMembrane ProteinsMiceMolecular WeightProtein TransportJournal Article

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Huan Tran, Roumen Pankov, Simon D Tran, Brian Hampton, Wilson H Burgess, Kenneth M Yamada. 2002-05-15. Integrin clustering induces kinectin accumulation.. https://doi.org/10.1242/jcs.115.10.2031

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