Research associated with oocyte maturation and early post fertilization development in amphibians includes 1) The nature of gonadotropin-steroid effects on follicle tissue and oocytes in bringing about ovulation and oocyte maturation. Studies on follicular tissue include a determination, using chromatography and radioimmunoassay of when (in relation to follicle size) tissue becomes competent to synthesize steroids in response to gonadotropins. Studies with oocytes concern steroid - surface interactions, analyzed by measuring changes in ion permeability and electrical resistance, and membrane isolation. Steroid receptor proteins are being studied by equilibrium dialysis and filtration on DEAE paper to determine when (during oogenesis) receptors first appear, and where they are located within the oocyte. Finally, various protein kinases are being isolated in attempts to identify an intracellular maturation inducing factor. 2) quantitative and qualitative analysis of RNA synthesis in oocytes during oogenesis, and during maturation, in relation to potential steroid and gonadotropin effects. Absolute rates of synthesis of stable and unstable RNA classes, separated on acrylamide gels, as well as pool specific activities. Studies also involve intracellular location of various RNA species (nucleus vs cytoplasm), turnover times, processing times, and transport times. Finally, studies on poly (A)plusRNA are being conducted, using oligo dt cellulose columns. 3) Identification of the cytoplasmic component involved in the formation of primordial germ cells is being pursued. Ultrastructural studies are used to "trace" distinctive electron dense "germinal material" throughout oogenesis and early development. Autoradiography is used to determine if this material incorporates radioactive precursors administered at various stages of oogenesis. Cell fractionation procedures are being tested in attempts to isolate the electron dense bodies directly.