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PubMed · 10649439

Specific decrease in the level of Hic-5, a focal adhesion protein, during immortalization of mouse embryonic fibroblasts, and its association with focal adhesion kinase.

K Ishino·Kaneyama·M Shibanuma·K Nose
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Abstract

Hic-5 is a paxillin homologue with four LIM domains in its C-terminal region, localized mainly in focal adhesions in normal fibroblasts. Hic-5 is also known to associate with focal adhesion kinase (FAK) or the related CAKbeta, and with vinculin. In the present study, we examined changes in Hic-5 and paxillin protein levels in primary mouse embryo fibroblasts (MEF) during mortal and immortal stages. The Hic-5 level was markedly decreased when cells became immortalized, whereas that of paxillin was increased. The vinculin level was not changed significantly. Hic-5 was mainly localized in focal adhesion plaques of mortal MEF but was localized in the nuclear periphery in the immortalized MEF; the number of focal adhesion plaques was decreased in these cells. Mouse Hic-5 contains three LD domains in its N-terminal half, and the first LD domain (LD1) appears to be involved in interaction with FAK. However, this interaction was not essential for recruitment of Hic-5 to focal adhesions, since its subcellular localization was similar in FAK(-/-) cells. Forced expression of Hic-5 decreased colony forming ability of MEF from FAK(+/+) mice, but not of FAK(-/-) cells. These observations suggested the involvement of Hic-5 in determination of cellular proliferative capacity in collaboration with other cytoskeletal components.

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Amino Acid SequenceAnimalsBase SequenceBinding SitesCell Adhesion MoleculesCell DivisionCells, CulturedCellular SenescenceColony-Forming Units AssayCytoskeletal ProteinsDNA PrimersDNA-Binding ProteinsEmbryo, MammalianFibroblastsFocal Adhesion Kinase 1Focal Adhesion Protein-Tyrosine KinasesLIM Domain ProteinsMiceMolecular Sequence DataPaxillinPhosphoproteinsProtein Structure, TertiaryProtein-Tyrosine KinasesSequence DeletionVinculinJournal ArticleResearch Support, Non-U.S. Gov't

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K Ishino, Kaneyama, M Shibanuma, K Nose. 2000. Specific decrease in the level of Hic-5, a focal adhesion protein, during immortalization of mouse embryonic fibroblasts, and its association with focal adhesion kinase.. https://doi.org/10.1002/(sici)1097-4644(20000301)76%3A3%3C411%3A%3Aaid-jcb9%3E3.0.co%3B2-j

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