title: Characterization of ring-like F-actin structure as a mechanical partner for spindle positioning in mitosis.
abstract: Proper spindle positioning and orientation are essential for accurate mitosis which requires dynamic interactions between microtubule and actin filament (F-actin). Although mounting evidence demonstrates the role of F-actin in cortical cytoskeleton dynamics, it remains elusive as to the structure and function of F-actin-based networks in spindle geometry. Here we showed a ring-like F-actin structure surrounding the mitotic spindle which forms since metaphase and maintains in MG132-arrested metaphase HeLa cells. This cytoplasmic F-actin structure is relatively isotropic and less dynamic. Our computational modeling of spindle position process suggests a possible mechanism by which the ring-like F-actin structure can regulate astral microtubule dynamics and thus mitotic spindle orientation. We further demonstrated that inhibiting Plk1, Mps1 or Myosin, and disruption of microtubules or F-actin polymerization perturbs the formation of the ring-like F-actin structure and alters spindle position and symmetric division. These findings reveal a previously unrecognized but important link between mitotic spindle and ring-like F-actin network in accurate mitosis and enables the development of a method to theoretically illustrate the relationship between mitotic spindle and cytoplasmic F-actin.
authors.affiliation: Anhui Key Laboratory of Cellular Dynamics and Chemical Biology, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: Huan
authors.initials: H
authors.lastname: Lu
authors.affiliation: Anhui Key Laboratory of Cellular Dynamics and Chemical Biology, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: Qun
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Anhui Key Laboratory of Cellular Dynamics and Chemical Biology, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Jiang
authors.affiliation: Anhui Key Laboratory of Cellular Dynamics and Chemical Biology, University of Science and Technology of China, Hefei, Anhui, China; Department of Physiology, Morehouse School of Medicine, Atlanta, Georgia, United States of America.
authors.forename: Tongge
authors.initials: T
authors.lastname: Zhu
authors.affiliation: Anhui Key Laboratory of Cellular Dynamics and Chemical Biology, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Xia
authors.affiliation: Department of Physiology, Morehouse School of Medicine, Atlanta, Georgia, United States of America.
authors.forename: William
authors.initials: W
authors.lastname: Seffens
authors.affiliation: Department of Physiology, Morehouse School of Medicine, Atlanta, Georgia, United States of America.
authors.forename: Felix
authors.initials: F
authors.lastname: Aikhionbare
authors.affiliation: Anhui Key Laboratory of Cellular Dynamics and Chemical Biology, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Wang
authors.affiliation: Anhui Key Laboratory of Cellular Dynamics and Chemical Biology, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Dou
authors.affiliation: Anhui Key Laboratory of Cellular Dynamics and Chemical Biology, University of Science and Technology of China, Hefei, Anhui, China.
authors.forename: Xuebiao
authors.initials: X
authors.lastname: Yao
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism; D000199:Actins / Q000378:metabolism*; D045744:Cell Line, Tumor; D003599:Cytoskeleton / Q000378:metabolism / Q000502:physiology; D006367:HeLa Cells; D006801:Humans; D008677:Metaphase / Q000502:physiology; D008870:Microtubules / Q000378:metabolism; D008938:Mitosis / Q000502:physiology*; D009218:Myosins / Q000378:metabolism; D008941:Spindle Apparatus / Q000378:metabolism* / Q000502:physiology*
chemical_list: D000199:Actins; D009218:Myosins