TY - JOUR
T1 - Actin-ring segment switching drives nonadhesive gap closure
AU - Wei, Qiong
AU - Shi, Xuechen
AU - Zhao, Tiankai
AU - Cai, Pingqiang
AU - Chen, Tianwu
AU - Zhang, Yao
AU - Huang, Changjin
AU - Yang, Jian
AU - Chen, Xiaodong
AU - Zhang, Sulin
N1 - Funding Information:
ACKNOWLEDGMENTS. S.Z. acknowledges support by the NIH (National Heart, Lung, and Blood Institute R21-HL122902) and NSF (Civil, Mechanical and Manufacturing Innovation-0754463/0644599). J.Y. was supported in part by National Institute of Arthritis and Musculoskeletal and Skin Diseases Award (AR072731).
Publisher Copyright:
© 2020 National Academy of Sciences. All rights reserved.
PY - 2020/12
Y1 - 2020/12
N2 - Gap closure to eliminate physical discontinuities and restore tissue integrity is a fundamental process in normal development and repair of damaged tissues and organs. Here, we demonstrate a nonadhesive gap closure model in which collective cell migration, large-scale actin-network fusion, and purse-string contraction orchestrate to restore the gap. Proliferative pressure drives migrating cells to attach onto the gap front at which a pluricellular actin ring is already assembled. An actin-ring segment switching process then occurs by fusion of actin fibers from the newly attached cells into the actin cable and defusion from the previously lined cells, thereby narrowing the gap. Such actin-cable segment switching occurs favorably at high curvature edges of the gap, yielding size-dependent gap closure. Cellular force microscopies evidence that a persistent rise in the radial component of inward traction force signifies successful actin-cable segment switching. A kinetic model that integrates cell proliferation, actin fiber fusion, and purse-string contraction is formulated to quantitatively account for the gap-closure dynamics. Our data reveal a previously unexplored mechanism in which cells exploit multifaceted strategies in a highly cooperative manner to close nonadhesive gaps.
AB - Gap closure to eliminate physical discontinuities and restore tissue integrity is a fundamental process in normal development and repair of damaged tissues and organs. Here, we demonstrate a nonadhesive gap closure model in which collective cell migration, large-scale actin-network fusion, and purse-string contraction orchestrate to restore the gap. Proliferative pressure drives migrating cells to attach onto the gap front at which a pluricellular actin ring is already assembled. An actin-ring segment switching process then occurs by fusion of actin fibers from the newly attached cells into the actin cable and defusion from the previously lined cells, thereby narrowing the gap. Such actin-cable segment switching occurs favorably at high curvature edges of the gap, yielding size-dependent gap closure. Cellular force microscopies evidence that a persistent rise in the radial component of inward traction force signifies successful actin-cable segment switching. A kinetic model that integrates cell proliferation, actin fiber fusion, and purse-string contraction is formulated to quantitatively account for the gap-closure dynamics. Our data reveal a previously unexplored mechanism in which cells exploit multifaceted strategies in a highly cooperative manner to close nonadhesive gaps.
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U2 - 10.1073/PNAS.2010960117
DO - 10.1073/PNAS.2010960117
M3 - Article
C2 - 33318201
AN - SCOPUS:85099172288
SN - 0027-8424
VL - 117
SP - 33263
EP - 33271
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 52
ER -