Articles by Mary L. Ladage in JoVE
Use of Time Lapse Microscopy to Visualize Anoxia-induced Suspended Animation in C. elegans Embryos Anastacia M. Garcia1, Mary L. Ladage1, Pamela A. Padilla1 1Department of Biological Sciences, University of North Texas Described here is an in vivo technique to image sub-cellular structures in animals exposed to anoxia using a gas flow through microincubation chamber in conjunction with a spinning disc confocal microscope. This method is straightforward and flexible enough to suit a variety of experimental parameters and model systems.
Other articles by Mary L. Ladage on PubMed
NPP-16/Nup50 Function and CDK-1 Inactivation Are Associated with Anoxia-induced Prophase Arrest in Caenorhabditis Elegans Molecular Biology of the Cell. Mar, 2010 | Pubmed ID: 20053678 Oxygen, an essential nutrient, is sensed by a multiple of cellular pathways that facilitate the responses to and survival of oxygen deprivation. The Caenorhabditis elegans embryo exposed to severe oxygen deprivation (anoxia) enters a state of suspended animation in which cell cycle progression reversibly arrests at specific stages. The mechanisms regulating interphase, prophase, or metaphase arrest in response to anoxia are not completely understood. Characteristics of arrested prophase blastomeres and oocytes are the alignment of condensed chromosomes at the nuclear periphery and an arrest of nuclear envelope breakdown. Notably, anoxia-induced prophase arrest is suppressed in mutant embryos lacking nucleoporin NPP-16/NUP50 function, indicating that this nucleoporin plays an important role in prophase arrest in wild-type embryos. Although the inactive form of cyclin-dependent kinase (CDK-1) is detected in wild-type-arrested prophase blastomeres, the inactive state is not detected in the anoxia exposed npp-16 mutant. Furthermore, we found that CDK-1 localizes near chromosomes in anoxia-exposed embryos. These data support the notion that NPP-16 and CDK-1 function to arrest prophase blastomeres in C. elegans embryos. The anoxia-induced shift of cells from an actively dividing state to an arrested state reveals a previously uncharacterized prophase checkpoint in the C. elegans embryo.
Suspended Animation, Diapause and Quiescence: Arresting the Cell Cycle in C. Elegans Cell Cycle (Georgetown, Tex.). May, 2012 | Pubmed ID: 22510566 Developing organisms require nutrients to support cell division vital for growth and development. An adaptation to stress, used by many organisms, is to reversibly enter an arrested state by reducing energy-requiring processes, such as development and cell division. This "wait it out" approach to survive stress until the environment is conductive for growth and development is used by many metazoans. Much is known about the molecular regulation of cell division, metazoan development and responses to environmental stress. However, how these biological processes intersect is less understood. Here, we review studies conducted in Caenorhabditis elegans that investigate how stresses such as oxygen deprivation (hypoxia and anoxia), exogenous chemicals or starvation affect cellular processes in the embryo, larvae or adult germline. Using C. elegans to identify how stress signals biological arrest can help in our understanding of evolutionary pressures as well as human health-related issues.