Dataset Information

Spatiotemporal organization, regulation, and functions of tractions during neutrophil chemotaxis.

ABSTRACT: Despite recent advances in our understanding of biochemical regulation of neutrophil chemotaxis, little is known about how mechanical factors control neutrophils' persistent polarity and rapid motility. Here, using a human neutrophil-like cell line and human primary neutrophils, we describe a dynamic spatiotemporal pattern of tractions during chemotaxis. Tractions are located at both the leading and the trailing edge of neutrophils, where they oscillate with a defined periodicity. Interestingly, traction oscillations at the leading and the trailing edge are out of phase with the tractions at the front leading those at the back, suggesting a temporal mechanism that coordinates leading edge and trailing edge activities. The magnitude and periodicity of tractions depend on the activity of nonmuscle myosin IIA. Specifically, traction development at the leading edge requires myosin light chain kinase-mediated myosin II contractility and is necessary for ?5?1-integrin activation and leading edge adhesion. Localized myosin II activation induced by spatially activated small GTPase Rho, and its downstream kinase p160-ROCK, as previously reported, leads to contraction of actin-myosin II complexes at the trailing edge, causing it to de-adhere. Our data identify a key biomechanical mechanism for persistent cell polarity and motility.

SUBMITTER: Shin ME

PROVIDER: S-EPMC2995358 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature

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Spatiotemporal organization, regulation, and functions of tractions during neutrophil chemotaxis.

Shin Myung Eun ME He Yuan Y Li Dong D Na Sungsoo S Chowdhury Farhan F Poh Yeh-Chuin YC Collin Olivier O Su Pei P de Lanerolle Primal P Schwartz Martin A MA Wang Ning N Wang Fei F

Blood 20100708 17

Despite recent advances in our understanding of biochemical regulation of neutrophil chemotaxis, little is known about how mechanical factors control neutrophils' persistent polarity and rapid motility. Here, using a human neutrophil-like cell line and human primary neutrophils, we describe a dynamic spatiotemporal pattern of tractions during chemotaxis. Tractions are located at both the leading and the trailing edge of neutrophils, where they oscillate with a defined periodicity. Interestingly, ...[more]

PMID: 20616216

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Dataset Information

Spatiotemporal organization, regulation, and functions of tractions during neutrophil chemotaxis.

Publications

Spatiotemporal organization, regulation, and functions of tractions during neutrophil chemotaxis.

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