ISOPRENYLATION OF POLYPEPTIDES IN THE NEMATODE CAENORHABDITIS-ELEGANS

Covalent modification of eucaryotic proteins, involving addition of is oprenyl groups, is a widespread phenomenon. Here we provide direct evi dence for this form of covalent modification in the free-living nemato de, Caenorhabditis elegans. Following incubation in the presence of [H -3]mevalonolactone, specific C. elegans polypeptides became labelled i n both aqueous and detergent (Triton X-114)-enriched extracts. Chemica l and CC-MS analysis of modifying groups, cleaved from C. elegans poly peptides, revealed that geranylgeranylation and, to a lesser extent, f arnesylation of target polypeptides occurred. Immunoblot analysis prov ided preliminary evidence that the ras-like let-60 polypeptide was a t arget for isoprenylation in C. elegans. (C) 1998 Elsevier Science B.V.