title: Acute heat shock leads to cortical domain internalization and polarity loss in the C. elegans embryo.
abstract: Many developmental processes are inherently robust due to network organization of the participating factors and functional redundancy. The heterogeneity of the factors involved and their connectivity puts these processes at risk of abrupt system collapse under stress. The polarization of the one-cell C. elegans embryo constitutes such an inherently robust process with functional redundancy. However, how polarization is affected by acute stress has not been thoroughly investigated. Here, we report that heat shock (34°C, 1 h) triggers a highly reproducible loss of the anterior and collapse of the posterior polarity domains. Temperature-dependent loss of cortical non-muscle myosin II drastically reduces cortical tension and leads to internalization of large plasma membrane domains including the membrane-associated polarity factor PAR-2. After internalization, plasma membrane vesicles and associated factors cluster around centrosomes and are thereby withdrawn from the polarization process. Transient formation of the posterior polarity domain suggests that microtubule-induced self-organization of this domain is not compromised after heat shock. Hence, our data uncover that the polarization system undergoes a temperature-dependent collapse under acute stress.
authors.affiliation: Buchmann Institute for Molecular Life Sciences and Institute of Biochemistry II, Goethe University, Max-von-Laue-Strasse 15, Frankfurt (Main), 60438, Germany.
authors.forename: Deepika
authors.initials: D
authors.lastname: Singh
authors.affiliation: Buchmann Institute for Molecular Life Sciences and Institute of Biochemistry II, Goethe University, Max-von-Laue-Strasse 15, Frankfurt (Main), 60438, Germany.
authors.forename: Devang
authors.initials: D
authors.lastname: Odedra
authors.affiliation: Buchmann Institute for Molecular Life Sciences and Institute of Biochemistry II, Goethe University, Max-von-Laue-Strasse 15, Frankfurt (Main), 60438, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Lehmann
authors.affiliation: Buchmann Institute for Molecular Life Sciences and Institute of Biochemistry II, Goethe University, Max-von-Laue-Strasse 15, Frankfurt (Main), 60438, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Pohl
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000196:embryology*; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism; D016764:Cell Polarity; D004625:Embryo, Nonmammalian / Q000502:physiology*; D018869:Heat-Shock Response; D006358:Hot Temperature; D024462:Myosin Type II / Q000378:metabolism; D013312:Stress, Physiological
chemical_list: D029742:Caenorhabditis elegans Proteins; D024462:Myosin Type II
keywords: actomyosin; asymmetric cell division; cortex; cortical flow; embryogenesis; polarity