The Sea Urchin Egg and Cortical Vesicles as Model Systems to Dissect the Fast, Ca2+-Triggered Steps of Regulated Exocytosis

  • Prabhodh S. Abbineni
  • Elise P. Wright
  • Tatiana P. Rogasevskaia
  • Murray C. Killingsworth
  • Chandra S. Malladi
  • Jens R. Coorssen
Part of the Neuromethods book series (NM, volume 83)


Exocytosis is a fundamental process utilized by all eukaryotic organisms; this elegantly efficient process mediates such diverse functions as fertilization, synaptic transmission, and wound healing. Membrane fusion, the defining step of this process, has been well conserved through evolution. However, the mechanisms defining the priming, docking, and merger of two apposed native bilayer membranes have not been fully elucidated. Sea urchin cortical vesicles are locked at a stage just prior to Ca2+-triggered membrane fusion and are thus an ideal system for fully defining the mechanisms underlying this process. Here we describe detailed methods to isolate these native secretory vesicles, monitor the fusion process, assess the minimal essential biochemical components, and identify their ultrastructural interactions that define the triggered exocytotic pathway.

Key words

Calcium Docking Exocytosis Membrane fusion Priming Secretory vesicle proteome/lipidome 



P.S.A. would like to thank the UWS School of Medicine for scholarship funding. EPW would like to thank Bellberry Limited for their donation to the UWS School of Medicine that provided a postdoctoral fellowship. J.R.C. acknowledges the support of the UWS School of Medicine and an anonymous private Australian foundation, as well as past support from the Canadian Institutes of Health Research, the Natural Sciences and Engineering Research Council of Canada, and the Alberta Heritage Foundation for Medical Research that made much of this work possible. The introduction was largely reproduced from a text box that appeared in one of our recent publications [30], and was reproduced here with the permission of the publisher (Elsevier).


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Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  • Prabhodh S. Abbineni
    • 1
  • Elise P. Wright
    • 1
  • Tatiana P. Rogasevskaia
    • 2
  • Murray C. Killingsworth
    • 1
    • 3
  • Chandra S. Malladi
    • 1
  • Jens R. Coorssen
    • 1
  1. 1.Department of Molecular Physiology, Molecular Medicine Research GroupSchool of Medicine, University of Western SydneyPenrith South DCAustralia
  2. 2.Department of Chemical and Biological SciencesMount Royal UniversityCalgaryCanada
  3. 3.Electron Microscopy LaboratoryNSW Health PathologyLiverpool BCAustralia

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