Cell-free translation of immunoglobulin G polypeptides by chicken bursal RNA

The acquisition of messenger RNA controlling the translation of immunoglobulin G was studied in the chicken bursa of Fabricius, using the cell-free translation system of wheat germ lysate. Total cellular RNA extracted by phenol-1% sodium dodecylsulphate (pH 5.0 at 50 degrees) incorporated [3H]-leucine maximally. Sodium dodecylsulphate polyacrylamide gel electrophoresis of the immune precipitates of cell-free products with anti-chick IgG showed that polypeptides of gamma- and light chains were synthesized by bursal RNA from 20-day embryos and one-week-old chicks; in addition, a polypeptide with a molecular size of about 4 x 10(4) was synthesized. No appreciable synthesis of gamma- and light chains by bursal RNA from 12-day embryos was found.