THE PEROXISOMAL TARGETING SIGNAL OF 3-OXOACYL-COA THIOLASE FROM SACCHAROMYCES-CEREVISIAE

All peroxisomal 3-oxoacyl-CoA thiolases identified so far do not contain the previously identified tripeptide peroxisomal targeting signal at their carboxy-termini. For the two rat thiolases it was shown that their peroxisomal targeting signals are localized within the amino-terminal region of the proteins and are cleaved upon import. This report demonstrates that the N-terminal region of the peroxisomal 3-oxoacyl-CoA thiolase from Saccharomyces cerevisiae is essential for its peroxisomal targeting, and that the N-terminal 16 amino acids of yeast thiolase are sufficient to target the otherwise cytosolic small subunit of ribulose-1,5-bisphosphate carboxylase to peroxisomes for import.