Dataset Information

Integrin Binding Dynamics Modulate Ligand-Specific Mechanosensing in Mammary Gland Fibroblasts.

ABSTRACT: The link between integrin activity regulation and cellular mechanosensing of tissue rigidity, especially on different extracellular matrix ligands, remains poorly understood. Here, we find that primary mouse mammary gland stromal fibroblasts (MSFs) are able to spread efficiently, generate high forces, and display nuclear YAP on soft collagen-coated substrates, resembling the soft mammary gland tissue. We describe that loss of the integrin inhibitor, SHARPIN, impedes MSF spreading specifically on soft type I collagen but not on fibronectin. Through quantitative experiments and computational modeling, we find that SHARPIN-deficient MSFs display faster force-induced unbinding of adhesions from collagen-coated beads. Faster unbinding, in turn, impairs force transmission in these cells, particularly, at the stiffness optimum observed for wild-type cells. Mechanistically, we link the impaired mechanotransduction of SHARPIN-deficient cells on collagen to reduced levels of collagen-binding integrin ?11?1. Thus integrin activity regulation and ?11?1 play a role in collagen-specific mechanosensing in MSFs.

SUBMITTER: Lerche M

PROVIDER: S-EPMC7044518 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Integrin Binding Dynamics Modulate Ligand-Specific Mechanosensing in Mammary Gland Fibroblasts.

Lerche Martina M Elosegui-Artola Alberto A Kechagia Jenny Z JZ Guzmán Camilo C Georgiadou Maria M Andreu Ion I Gullberg Donald D Roca-Cusachs Pere P Peuhu Emilia E Ivaska Johanna J

iScience 20200213 3

The link between integrin activity regulation and cellular mechanosensing of tissue rigidity, especially on different extracellular matrix ligands, remains poorly understood. Here, we find that primary mouse mammary gland stromal fibroblasts (MSFs) are able to spread efficiently, generate high forces, and display nuclear YAP on soft collagen-coated substrates, resembling the soft mammary gland tissue. We describe that loss of the integrin inhibitor, SHARPIN, impedes MSF spreading specifically on ...[more]

PMID: 32106057

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Dataset Information

Integrin Binding Dynamics Modulate Ligand-Specific Mechanosensing in Mammary Gland Fibroblasts.

Publications

Integrin Binding Dynamics Modulate Ligand-Specific Mechanosensing in Mammary Gland Fibroblasts.

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