title: ER-PM Contacts Define Actomyosin Kinetics for Proper Contractile Ring Assembly.
abstract: The cortical endoplasmic reticulum (ER), an elaborate network of tubules and cisternae [1], establishes contact sites with the plasma membrane (PM) through tethering machinery involving a set of conserved integral ER proteins [2]. The physiological consequences of forming ER-PM contacts are not fully understood. Here, we reveal a kinetic restriction role of ER-PM contacts over ring compaction process for proper actomyosin ring assembly in Schizosaccharomyces pombe. We show that fission yeast cells deficient in ER-PM contacts exhibit aberrant equatorial clustering of actin cables during ring assembly and are particularly susceptible to compromised actin filament crosslinking activity. Using quantitative image analyses and computer simulation, we demonstrate that ER-PM contacts function to modulate the distribution of ring components and to constrain their compaction kinetics. We propose that ER-PM contacts have evolved as important physical modulators to ensure robust ring assembly.
authors.affiliation: Temasek Life Sciences Laboratory, 1 Research Link, Singapore 117604, Singapore. Electronic address: zhangdan@tll.org.sg.
authors.forename: Dan
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Department of Physics, Lehigh University, Bethlehem, PA 18015, USA.
authors.forename: Tamara C
authors.initials: TC
authors.lastname: Bidone
authors.affiliation: Department of Physics, Lehigh University, Bethlehem, PA 18015, USA. Electronic address: vavylonis@lehigh.edu.
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Vavylonis
mesh_terms: D000205:Actomyosin / Q000378:metabolism*; D002462:Cell Membrane / Q000502:physiology*; D048749:Cytokinesis; D004721:Endoplasmic Reticulum / Q000502:physiology*; D007700:Kinetics; D012568:Schizosaccharomyces / Q000502:physiology*; D029702:Schizosaccharomyces pombe Proteins / Q000378:metabolism
chemical_list: D029702:Schizosaccharomyces pombe Proteins; D000205:Actomyosin