title: Protease-dead separase is dominant negative in the C. elegans embryo.
abstract: Separase is a protease that promotes chromosome segregation at anaphase by cleaving cohesin. Several non-proteolytic functions of separase have been identified in other organisms. We created a transgenic C. elegans line that expresses protease-dead separase in embryos to further characterize separase function. We find that expression of protease-dead separase is dominant-negative in C. elegans embryos, not previously reported in other systems. The C. elegans embryo is an ideal system to study developmental processes in a genetically tractable system. However, a major limitation is the lack of an inducible gene expression system for the embryo. We have developed two methods that allow for the propagation of lines carrying dominant-negative transgenes and have applied them to characterize expression of protease-dead separase in embryos. Using these methods, we show that protease-dead separase causes embryo lethality, and that protease-dead separase cannot rescue separase mutants. These data suggest that protease-dead separase interferes with endogenous separase function, possibly by binding substrates and protecting them from cleavage.
authors.affiliation: Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee, United States of America.
authors.forename: Diana M
authors.initials: DM
authors.lastname: Mitchell
authors.affiliation: Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee, United States of America.
authors.forename: Lindsey R
authors.initials: LR
authors.lastname: Uehlein-Klebanow
authors.affiliation: Department of Biochemistry, Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee, United States of America.
authors.forename: Joshua N
authors.initials: JN
authors.lastname: Bembenek
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D017173:Caenorhabditis elegans / Q000196:embryology*; D004625:Embryo, Nonmammalian / Q000201:enzymology*; D049452:Green Fluorescent Proteins / Q000235:genetics; D010447:Peptide Hydrolases / Q000378:metabolism*; D064247:Separase / Q000235:genetics / Q000378:metabolism*
chemical_list: D049452:Green Fluorescent Proteins; D010447:Peptide Hydrolases; D064247:Separase