RRC ID 20808
Author Shinozaki A, Sato N, Hayashi Y.
Title Peroxisomal targeting signals in green algae.
Journal Protoplasma
Abstract Peroxisomal enzymatic proteins contain targeting signals (PTS) to enable their import into peroxisomes. These targeting signals have been identified as PTS1 and PTS2 in mammalian, yeast, and higher plant cells; however, no PTS2-like amino acid sequences have been observed in enzymes from the genome database of Cyanidiochyzon merolae (Bangiophyceae), a primitive red algae. In studies on the evolution of PTS, it is important to know when their sequences came to be the peroxisomal targeting signals for all living organisms. To this end, we identified a number of genes in the genome database of the green algae Chlamydomonas reinhardtii, which contains amino acid sequences similar to those found in plant PTS. In order to determine whether these sequences function as PTS in green algae, we expressed modified green fluorescent proteins (GFP) fused to these putative PTS peptides under the cauliflower mosaic virus 35S promoter. To confirm whether granular structures containing GFP-PTS fusion proteins accumulated in the peroxisomes of Closterium ehrenbergii, we observed these cells after the peroxisomes were stained with 3, 3'-diaminobenzidine. Our results confirm that the GFP-PTS fusion proteins indeed accumulated in the peroxisomes of these green algae. These findings suggest that the peroxisomal transport system for PTS1 and PTS2 is conserved in green algal cells and that our fusion proteins can be used to visualize peroxisomes in live cells.
Volume 235(1-4)
Pages 57-66
Published 2009-3
DOI 10.1007/s00709-009-0031-1
PMID 19214701
MeSH Chlorophyta / metabolism* Chlorophyta / ultrastructure Green Fluorescent Proteins / metabolism Microscopy, Electron, Transmission Mitochondria / metabolism Mitochondria / ultrastructure Organisms, Genetically Modified / genetics Organisms, Genetically Modified / metabolism Peroxisomal Targeting Signal 2 Receptor Peroxisome-Targeting Signal 1 Receptor Peroxisomes / metabolism* Peroxisomes / ultrastructure Receptors, Cytoplasmic and Nuclear / metabolism* Recombinant Fusion Proteins / metabolism* Signal Transduction
IF 2.633
Times Cited 14
Algae NIES-228