...Josephine Bradley; Iestyn Pope; Yisu Wang; Wolfgang Langbein; Paola Borri; Karl Swann ABSTRACT Mammalian eggs generate most of their ATP by mitochondrial oxidation of pyruvate from the surrounding medium or from fatty acids that are stored as triacylglycerols within lipid droplets. The balance...

...Jose Raul Gonzalez-Garcia; Josephine Bradley; Michail Nomikos; Laboni Paul; Zoltan Machaty; F. Anthony Lai; Karl Swann ABSTRACT Egg activation at fertilization in mammals is initiated by prolonged Ca 2+ oscillations that trigger the completion of meiosis and formation of pronuclei. A fall...

...Wen Ling Zhang; Philippe Huitorel; Anne-Marie Geneviere; Sandrine Chiri; Brigitte Ciapa Unfertilized sea urchin eggs that are arrested at G1 phase after completion of meiosis contain a highly phosphorylated mitogen-activated protein (MAP) kinase (MAPK), the ERK-like protein (ERK-LP). Several data...

...Kathryn K. Stein; Paul Primakoff; Diana Myles Sperm-egg fusion is a cell-cell membrane fusion event essential for the propagation of sexually reproducing organisms. In gamete fusion, as in other fusion events, such as virus-cell and intracellular vesicle fusion, membrane fusion is a two-step...

... system of the echinoderm egg to determine if NSF is an essential factor in membrane fusion during Ca 2+ -triggered exocytosis. Neither exocytosis in vitro, nor homotypic cortical vesicle (CV) fusion required soluble proteins or nucleotides, and both occurred in the presence of non-hydrolyzable analogs...

... homology (PH) domain from phospholipase Cδ1 coupled to green fluorescent protein (GFP) that binds PtdIns(4,5) P 2 . We found that eggs in Ca 2+ -free sea water displayed Ca 2+ waves that originated from the CP, showing that enhanced CP Ca 2+ influx does not determine the origin of the pacemaker. Also...

...Rémi Dumollard; John Carroll; Geneviève Dupont; Christian Sardet During the past 25 years, the characterization of sperm-triggered calcium signals in eggs has progressed from the discovery of a single calcium increase at fertilization in the medaka fish to the observation of repetitive calcium...

...Karen A. Becker; Nathan H. Hart SUMMARY The zebrafish egg provides a useful experimental system to study events of fertilization, including exocytosis. We show by differential interference contrast videomicroscopy that cortical granules are: (1) released nonsynchronously over the egg surface and (2...

..., unrelated to that of maturation promoting factor, can sometimes be detected during mitotic divisions in various types of cells and oocytes. We have reinvestigated this problem in order to determine the origin and the role of MBP kinase that is stimulated at time of mitosis in the fertilized eggs of the sea...

...Céline De Nadai; Philippe Huitorel; Sandrine Chiri; Brigitte Ciapa ABSTRACT We have reported earlier that the polyphosphoinositide messenger system may control mitosis in sea urchin eggs. Besides phospholipase C activation and its second messengers, phosphatidylinositol (PI) 3-kinase has been...