Farnesylation of Batten Disease CLN3 Protein

Abstract The carboxyl terminal of the predicted amino acid sequence of the Batten disease CLN3 gene protein is CQLS. This motif is expected to be a site for farnesylation at the cysteine residue. In order to determine whether this is indeed farnesylated we have carried out the in-vitro prenylation of tetrapeptides CVLS, CAIL and CQLS using a farnesyl transferase preparation from bovine brain. The data shows that the CQLS is a good acceptor of a farnesyl group similar to CVLS while it is a poor acceptor of a geranylgeranyl group unlike CAIL, which is a good acceptor of a geranylgeranyl group. This suggests that the CLN3 gene product may be a farnesylated protein.