BIOCHEMICAL ISOLATION AND PHYSIOLOGICAL IDENTIFICATION OF EGG-LAYING HORMONE IN APLYSIA-CALIFORNICA

The bag cells of A. californica produce 2 polypeptide species that comigrate on electrophoretic gels containing sodium dodecyl sulfate [SDS]. By this separation procedure both species can be assigned a MW of .apprx. 6000. One of these molecules has an Rf of 0.65 on alkaline discontinuous electrophoresis gels, an isoelectric point at pH 4.8, a gel filtration MW of .apprx. 12,000 and has no known biological function. The other does not enter alkaline disk gels, has an isoelectric point at pH .apprx. 9.3, shows a gel filtration molecular weight consistent with that determined by SDS gel electrophoresis and is the egg-laying hormone.