Translation of Polarity Cues into Asymmetric Spindle Positioning in Caenorhabditis elegans Embryos

• Published in: Science (American Association for the Advancement of Science) 2003-06, Vol.300 (5627), p.1957-1961
• Main Authors: Colombo, Kelly, Grill, Stephan W., Kimple, Randall J., Willard, Francis S., Siderovski, David P., Gönczy, Pierre
• Format: Article
• Language: English
• Subjects: Anaphase; Animals; Animals, Genetically Modified; Biological and medical sciences; Caenorhabditis elegans - cytology; Caenorhabditis elegans - embryology; Caenorhabditis elegans - genetics; Caenorhabditis elegans - physiology; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - metabolism; Cell cycle; Cell Division; Cell Polarity; Cellular biology; Cues; Early stages. Segmentation. Gastrulation. Neurulation; Embryogenesis; Embryology: invertebrates and vertebrates. Teratology; Embryos; Epidemics; Fundamental and applied biological sciences. Psychology; Grade Point Average; GTP-Binding Proteins - genetics; GTP-Binding Proteins - metabolism; Literary Devices; Long term potentiation; Muscle spindles; Neurons; Neuroscience; Phenotype; Phenotypes; Protein Subunits - genetics; Protein Subunits - metabolism; Recombinant Fusion Proteins - metabolism; RNA Interference; Signal Transduction; Spindle Apparatus - physiology; Spindle Apparatus - ultrastructure; Two-Hybrid System Techniques
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1084146

Asymmetric divisions are crucial for generating cell diversity; they rely on coupling between polarity cues and spindle positioning, but how this coupling is achieved is poorly understood. In one-cell stage Caenorhabditis elegans embryos, polarity cues set by the PAR proteins mediate asymmetric spindle positioning by governing an imbalance of net pulling forces acting on spindle poles. We found that the GoLoco-containing proteins GPR-1 and GPR-2, as well as the Gα subunits GOA-1 and GPA-16, were essential for generation of proper pulling forces. GPR-1/2 interacted with guanosine diphosphate-bound GOA-1 and were enriched on the posterior cortex in a par-3- and par-2-dependent manner. Thus, the extent of net pulling forces may depend on cortical Gα activity, which is regulated by anterior-posterior polarity cues through GPR-1/2.