The state of actin in the isolated cortex of the unfertilized sea urchin egg can be controlled by experimentally manipulating the pH of the isolation medium. Cortices isolated at the pH of the unfertilized egg (6.5--6.7) do not contain filamentous actin, while those isolated at the pH of the fertilized egg (7.3--7.5) develop large numbers of microvilli which contain bundles of actin filaments. Cortices that are isolated at pH 6.5 and then transferred to isolation medium buffered at pH 7.5 also develop actin filaments. However, the filaments are not arranged in bundles and microvilli do not form. Although the cortical granules in cortices isolated at pH 6.5 discharge at a free Ca++ concentration of approximately 10 micrometer, actin polymerization is not induced by increasing the Ca++ concentration of the isolation medium. These results suggest that the increase in cytoplasmic pH which occurs following fertilization induces the polymerization of actin in the egg cortex.
The polymerization of actin. III. Aggregates of nonfilamentous actin and its associated proteins: a storage form of actin
The contractile basis of ameboid movement. II. Structure and contractility of motile extracts and plasmalemma-ectoplasm ghosts
Polymerization of actin. IV. Role of Ca++ and H+ in the assembly of actin and in membrane fusion in the acrosomal reaction of echinoderm sperm
Intracellular calcium release and the mechanisms of parthenogenetic activation of the sea urchin egg
Actin polymerizability is influenced by profilin, a low molecular weight protein in non-muscle cells
The visualization of actin filament polarity in thin sections. Evidence for the uniform polarity of membrane-associated filaments
The contractile basis of amoeboid movement. I. The chemical control of motility in isolated cytoplasm
Methods for revoval of the vitelline membrane of sea urchin eggs. I. Use of dithiothreitol (Cleland Reagent)
Relative changes in F-actin during the first cell cycle: evidence for two distinct pools of F-actin in the sea urchin egg
Stimulation of cortical actin polymerization in the sea urchin egg cortex by NH4Cl, procaine and urethane: elevation of cytoplasmic pH is not the common mechanism of action
Characterization of sea urchin unconventional myosins and analysis of their patterns of expression during early embryogenesis
Multiple intracellular signals coordinate structural dynamics in the sea urchin egg cortex at fertilization
Reception and transduction of the serotonin signal responsible for meiosis reinitiation in oocytes of the Japanese clam Ruditapes philippinarum
The effective membrane capacity of Xenopus eggs: its relations with membrane conductance and cortical granule exocytosis
Reassociation of cortical secretory vesicles with sea urchin egg plasma membrane: assessment of binding specificity
Hyperosmolality inhibits exocytosis in sea urchin eggs by formation of a granule-free zone and arrest of pore widening
The effect of local anesthetics and ammonia on cortical granule-plasma membrane attachment in the sea urchin egg
Postfertilization growth of microvilli in the sea urchin egg: new views from eggs that have been quick-frozen, freeze-fractured, and deeply etched
Release of glucose-6-phosphate dehydrogenase from cortex of Spisula eggs at fertilization and its recombination after meiosis
Relation of cytoplasmic alkalinization to microvillar elongation and microfilament formation in the sea urchin egg
Internal pH of Xenopus oocytes: a study of the mechanism and role of pH changes during meiotic maturation
Sea urchin egg cortical granule exocytosis is followed by a burst of membrane retrieval via uptake into coated vesicles
Cortical vesicle exocytosis in isolated cortices of sea urchin eggs: description of a turbidometric assay and its utilization in studying effects of different media on discharge
The cortical actin-membrane cytoskeleton of unfertilized sea urchin eggs: analysis of the spatial organization and relationship of filamentous actin, nonfilamentous actin, and egg spectrin
Subcellular localization of sea urchin egg spectrin: evidence for assembly of the membrane-skeleton on unique classes of vesicles in eggs and embryos
Sea urchin spectrin in oogenesis and embryogenesis: a multifunctional integrator of membrane-cytoskeletal interactions
Tubulin dynamics during the cytoplasmic cohesiveness cycle in artificially activated sea urchin eggs
Effects of oocyte exposure to local anesthetics on in vitro fertilization and embryo development in the mouse
Alpha-actinin from sea urchin eggs: biochemical properties, interaction with actin, and distribution in the cell during fertilization and cleavage
Induction of either contractile or structural actin-based gels in sea urchin egg cytoplasmic extract
Secretory protein decondensation as a distinct, Ca2+-mediated event during the final steps of exocytosis in Paramecium cells
Partial reconstruction of the microvillus core bundle: characterization of villin as a Ca++-dependent, actin-bundling/depolymerizing protein
Structural organization of actin in the sea urchin egg cortex: microvillar elongation in the absence of actin filament bundle formation
Strongylocentrotus purpuratus spindle tubulin. I. Characteristics of its polymerization and depolymerization in vitro
An actin-depolymerizing protein (depactin) from starfish oocytes: properties and interaction with actin
The changes in structural organization of actin in the sea urchin egg cortex in response to hydrostatic pressure
A 45,000-mol-wt protein-actin complex from unfertilized sea urchin egg affects assembly properties of actin
A developmentally regulated Na-H exchanger in Dictyostelium discoideum is necessary for cell polarity during chemotaxis
In vivo phosphorylation of regulatory light chain of myosin II in sea urchin eggs and its role in controlling myosin localization and function during cytokinesis
State of actin during the cycle of cohesiveness of the cytoplasm in parthenogenetically activated sea urchin egg
Parthenogenetic activation of sea urchin egg induces a cyclical variation of the cytoplasmic resistance to hexylene glycol-Triton X-100 treatment
The possible implication of membrane-associated actin in stimulus-secretion coupling in adrenal chromaffin cells
Villin is a major protein of the microvillus cytoskeleton which binds both G and F actin in a calcium-dependent manner
Effects of phalloidin microinjection and localization of fluorescein-labeled phalloidin in living sand dollar eggs
Isolation and characterization of sea urchin egg spectrin: calcium modulation of the spectrin-actin interaction
Accumulation of fluorescently labeled actin in the cortical layer in sea urchin eggs after fertilization
Unfertilized sea urchin eggs contain a discrete cortical shell of actin that is subdivided into two organizational states
Effects of early cleavage patterns of human embryos on subsequent in vitro development and implantation
Altering intracellular pH disrupts development and cellular organization in preimplantation hamster embryos
Latrunculin inhibits the microfilament-mediated processes during fertilization, cleavage and early development in sea urchins and mice
Effects of laser-assisted hatching and exposure time to vitrification solution on mouse embryo development
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