Modulation of Ovalbumin Synthesis by Estradiol-17β and Actinomycin D as Studied in Explants of Chick Oviduct in Culture

摘要: Abstract A secondary administration of estradiol-17β to chicks augments the incorporation 3H-uridine and 3H-lysine into oviduct magnum RNA protein, respectively. The isotopes ovalbumin, major protein synthesized by this tissue, is enhanced a greater extent than total protein. There concomitant organization monosomes polysomes during first 9 hours stimulation. Actinomycin D, at dose 5 mg per kg, blocks estrogen-mediated increase in isotope RNA, ovalbumin. At slightly lower actinomycin 2 induction synthesis, including almost normal, although bulk inhibited nearly same as higher dose. Isotope ribosomal appears be selectively inhibited. This result agrees with earlier findings which suggested that rRNA synthesis not required for ovalbumin early Although we have tried several hormonal combinations chick sera, been unable induce explants tissue culture. Once has induced vivo, however, continues electrophoretic pattern on sodium dodecyl sulfate acrylamide gels soluble proteins vivo culture are same. Thus, technique can used confidently measure specific proteins. Protein was investigated both short (20 min) long term (30 hour) cultures. Kinetic studies incubations suggest released from rate average Insulin necessary cultures maintain protein; it no differential effect synthesis. During 30-hour period, declines relative half-life about 14 hours. addition D inhibits 95%, but little synthesis; nonsecretory (half-life = 7 hours). secretory proteins, conalbumin, become larger proportion after treatment. We conclude messenger (or some factor regulates synthesis) culture, longer intrinsic mRNA factors). details immunoprecipitation methods employed detect presented. gel verify precipitation general applicability proving specificity antigens radioactive homogenates.