PERILITUS-COCCINELLAE TERATOCYTE POLYPEPTIDE - EVIDENCE FOR PRODUCTION OF A TERATOCYTE-SPECIFIC 540 KDA PROTEIN

The proteins synthesized by teratocytes of the braconid wasp Perilitus coccinellae were analyzed electrophoretically. Non-denaturing polyacr ylamide gel electrophoresis (PAGE) revealed that the teratocytes conta ined a major polypeptide with a high molecular weight of about 540 kDa , SDS-PAGE indicated that the major subunit of this protein was approx . 94 kDa. The teratocytes were cultured in vitro in a medium containin g S-35-methionine. Both the proteins from the incubated teratocytes an d the medium were subjected to PAGE followed by fluorography. The fluo rogram revealed that the teratocytes synthesized the 540 kDa protein. RNAs extracted from the teratocytes, parasitoid larvae and host fat bo dy were translated in vitro in a rabbit reticulocyte lysate. Only the translation products of teratocyte RNA reacted with the antibodies gen erated against the crude teratocyte extract. Changes in the total prot ein content of teratocytes and parasitoid larvae indicated that the te ratocytes may have a role in providing nutrients for the developing pa rasitoid larvae during parasitism. This hypothesis was supported by th e fact that the gut contents of the parasitoid larvae showed an immuno reaction to antibodies against crude teratocyte proteins.