Anillin regulates cell-cell junction integrity by organizing junctional accumulation of Rho-GTP and actomyosin.
Anillin is a scaffolding protein that organizes and stabilizes actomyosin contractile rings and was previously thought to function primarily in cytokinesis [1-10]. Using Xenopus laevis embryos as a model system to examine Anillin's role in the intact vertebrate epithelium, we find that a population of Anillin surprisingly localizes to epithelial cell-cell junctions throughout the cell cycle, whereas it was previously thought to be nuclear during interphase [5, 11]. Furthermore, we show that Anillin plays a critical role in regulating cell-cell junction integrity. Both tight junctions and adherens junctions are disrupted when Anillin is knocked down, leading to altered cell shape and increased intercellular spaces. Anillin interacts with Rho, F-actin, and myosin II [3, 8, 9], all of which regulate cell-cell junction structure and function. When Anillin is knocked down, active Rho (Rho-guanosine triphosphate [GTP]), F-actin, and myosin II are misregulated at junctions. Indeed, increased dynamic "flares" of Rho-GTP are observed at cell-cell junctions, whereas overall junctional F-actin and myosin II accumulation is reduced when Anillin is depleted. We propose that Anillin is required for proper Rho-GTP distribution at cell-cell junctions and for maintenance of a robust apical actomyosin belt, which is required for cell-cell junction integrity. These results reveal a novel role for Anillin in regulating epithelial cell-cell junctions.
The Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109, USA.
Ciara C
CC
Reyes
Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA.
Meiyan
M
Jin
The Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109, USA.
Elaina B
EB
Breznau
Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA.
Rhogelyn
R
Espino
Biomedical Imaging Group, École Polytechnique Fédérale de Lausanne, Lausanne 1015, Switzerland.
Ricard
R
Delgado-Gonzalo
Centre for Systems Biology, School of Biological Sciences, The University of Edinburgh, Mayfield Road, Edinburgh EH9 3JR, Scotland, UK.
Andrew B
AB
Goryachev
The Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, MI 48109, USA; Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA. Electronic address: annlm@umich.edu.
Ann L
AL
Miller
D000199:Actins / Q000235:genetics / Q000378:metabolism; D000205:Actomyosin / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D003285:Contractile Proteins / Q000235:genetics* / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000235:genetics / Q000378:metabolism; D007365:Intercellular Junctions / Q000378:metabolism*; D024462:Myosin Type II / Q000235:genetics / Q000378:metabolism; D012234:Rho Factor / Q000235:genetics* / Q000378:metabolism; D014982:Xenopus laevis / Q000196:embryology / Q000235:genetics* / Q000378:metabolism
D000199:Actins; D003285:Contractile Proteins; D012234:Rho Factor; C095886:anillin; D006160:Guanosine Triphosphate; D000205:Actomyosin; D024462:Myosin Type II