Post-translational modification of rat immunoglobulins synthesized in the Xenopus oocyte translation system.

The post-translational modification of rat immunoglobulin synthesised in Xenopus laevis oocytes was studied. The major products of translation of rat spleen poly-(A) containing mRNA were found to be assembled 7S immunoglobulin molecules indicating extensive modification of primary translation products. The possibility that these immunoglobulin molecules might include antibodies of defined specificity was investigated using spleen mRNA from rats hyperimmunized with ferritin and keyhole limpet haemocyanin. The presence of antibodies to immunizing antigen in oocyte translation products was determined by affinity chromatography on Sepharose-antigen columns and the synthesis of Sepharose-antigen binding antibodies was observed, equivalent to 2.5-3% of total immunoglobulins. The oocyte produced antibodies were of the same immunoglobulin class as the circulating antibodies from the immunized rats.