The carboxy-terminal end of glycolate oxidase directs a foreign protein into tobacco leaf peroxisomes.
The carboxy-terminal residues of several peroxisomal proteins were shown to act as a peroxisomal targetting signal. This study was conducted to test whether the C-terminus of glycolate oxidase, a key enzyme in the glycolate metabolism pathway, is functioning as a targetting signal that directs proteins into plant leaf peroxisomes. A chimeric gene coding for a fusion protein composed of the C-terminal-truncated beta-glucuronidase, a synthetic linker of four amino acids and the last six C-terminal amino acids of glycolate oxidase, was constructed. Transformation of tobacco plants with the chimeric gene resulted in expression of beta-glucuronidase enzymic activity. About 50% of the transgenic beta-glucuronidase activity was localized to the peroxisomes. The results indicate that the six C-terminal amino acid residues of glycolate oxidase act as a targetting signal that is recognized by leaf peroxisomes.
Volokita
M
M
Biochemistry Department, Weizmann Institute of Science, Rehovot, Israel.
D000429:Alcohol Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D015870:Gene Expression; D005966:Glucuronidase / Q000235:genetics / Q000378:metabolism; D008830:Microbodies / Q000378:metabolism; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000378:metabolism*; D010944:Plants / Q000235:genetics / Q000378:metabolism*; D010947:Plants, Toxic; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D013347:Subcellular Fractions / Q000378:metabolism; D014026:Nicotiana / Q000235:genetics / Q000378:metabolism
D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D004247:DNA; D000429:Alcohol Oxidoreductases; C020821:glycollate oxidase; D005966:Glucuronidase