title: Self-organization and advective transport in the cell polarity formation for asymmetric cell division.
abstract: Anterior-Posterior (AP) polarity formation of cell membrane proteins plays a crucial role in determining cell asymmetry, which depends not only on the several genetic process but also biochemical and biophysical interactions. The mechanism of AP formation of Caenorhabditis elegans embryo is characterized into the three processes: (i) membrane association and dissociation of posterior and anterior proteins, (ii) diffusion into the membrane and cytosol, and (iii) active cortical and cytoplasmic flows induced by the contraction of the acto-myosin cortex. We explored the mechanism of symmetry breaking and AP polarity formation using self-recruitment model of posterior proteins. We found that the AP polarity pattern is established over wide range in the total mass of polarity proteins and the diffusion ratio in the cytosol to the membrane. We also showed that the advective transport in both membrane and cytosol during the establishment phase affects optimal time interval of establishment and positioning of the posterior domain, and plays a role to increase the robustness in the AP polarity formation by reducing the number of posterior domains for the sensitivity of initial conditions. We also demonstrated that a proper ratio of the total mass to cell size robustly regulate the length scale of the posterior domain.
authors.affiliation: Department of Mathematical and Life Sciences, Hiroshima University, Kagamiyama 1-3-1, Higashi-hiroshima 739-8530, Japan. Electronic address: seirin@hiroshima-u.ac.jp.
authors.forename: Sungrim
authors.initials: S
authors.lastname: Seirin Lee
authors.affiliation: RIKEN Quantitative Biology Center, 6-2-3 Furuedai, Suita, Osaka 565-0874, Japan; RIKEN Center for Developmental Biology, Minatojima-Minamimachi 2-2-3, Kobe 650-0047, Japan. Electronic address: tatsuoshibata@cdb.riken.jp.
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Shibata
mesh_terms: D000818:Animals; D060049:Asymmetric Cell Division; D017173:Caenorhabditis elegans / Q000166:cytology*; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D016764:Cell Polarity; D048429:Cell Size; D008954:Models, Biological; D021381:Protein Transport; D013997:Time Factors
chemical_list: D029742:Caenorhabditis elegans Proteins
keywords: Asymmetric cell division; Cell polarity; Convection reaction–diffusion model; Pattern formation