Serum Protein Synthesis by Embryonic and Neonatal Chicks

Abstract
Production of radioactively labeled serum proteins by chick embryos and neonatal chicks, following injection of S-35 methionine, was investigated. Sera were analyzed by immuno-electrophoresis, and labeled proteins were identified by autoradio-graphy of immunoelectrophoretic patterns. In addition to albumin and a few [alpha] and [beta] proteins, 3 proteins which migrated electrophoretically with the gamma-globulins were labeled in experimental sera. Gamma-globulin and [beta]2-macroglobulin were not labeled. A prealbumin and gamma-globulin were present in lower concentrations in sera of 12 day old than of newborn chicks.