Sperm-induced currents at fertilization in sea urchin eggs injected with EGTA and neomycin

Membrane and lipid dynamics at fertilization in sea urchin eggs

Sperm binding and fertilization envelope formation in a cell surface complex isolated from sea urchin eggs

An isolated surface complex consisting of the vitelline layer, plasma membrane, and attached secretory vesicles has been examined for its ability to bind sperm and to form the fertilization envelope. Isolated surface complexes (or intact eggs) fixed in glutaraldehyde and then washed in artificial sea water are capable of binding sperm in a species-specific manner. Sperm which bind to the isolat...

Propagation of transient Ca2+ increase in sea urchin eggs upon fertilization and its regulation by microinjecting EGTA solution.

Upon fertilization, the concentration of intracellular Ca2+ (Cai) in sea urchin eggs increased up to 3 microM when measured with fura-2, a fluorescent Ca indicator and the increase in Cai traversed from the sperm entry point as a wave over the entire egg at the mean propagation velocities of 5.0 microns/sec in C. japonicus egg and 5.3 microns/sec in H. pulcherrimus egg. However, the velocity wa...

Sperm Receptivity in Sea Urchin Oocytes and Eggs

An electrophysiological method for studying the receptivity to spermatozoa of sea urchin eggs and oocytes is described. Pairs of adjacent oocytes and eggs, with intact jelly layers, were impaled and simultaneously exposed to a known concentration of spermatozoa. Two parameters were studied. The time from insemination to the first successful collision (as indicated by a step depolarization acros...

Solubility Changes of Proteins in Sea Urchin Eggs upon Fertilization

The results presented in this paper give evidence of changes in solubility occurring in a protein fraction of the eggs of Arbacia lixula upon fertilization. The electrophoretic analysis indicates that it is only one part of one of the components of the KCl fraction that undergoes the change. However, under some experimental conditions (freezing and thawing of the KCl fraction or extraction of t...