Journal Article

Identification and analysis of the plant peroxisomal targeting signal 1 receptor NtPEX5

Kragler, F. (Universitat Wien, Vienna, Austria.), Christmann, J, Hartig, A, Lametschwandtner, G, Harada, J.J

1998

Overview

Protein translocation into peroxisomes takes place via recognition of a peroxisomal targeting signal present at either the extreme C termini (PTS1) or N termini (PTS2) of matrix proteins. In mammals and yeast, the peroxisomal targeting signal receptor. Pex5p, recognizes the PTS1 consisting of -SKL or variants thereof. Although many plant peroxisomal matrix proteins are transported through the PTS1 pathway, little is known about the PTS1 receptor or any other peroxisome assembly protein from plants. We cloned tobacco (Nicotiana tabacum) cDNAs encoding Pex5p (NtPEX5) based on the protein's interaction with a PTS1-containing protein in the yeast two-hybrid system. Nucleotide sequence analysis revealed that the tobacco Pex5p contains seven tetratricopeptide repeats and that NtPEX5 shares greater sequence similarity with its homolog from humans than from yeast. Expression of NtPEX5 fusion proteins, consisting of the N-terminal part of yeast Pex5p and the C-terminal region of NtPEX5, in a Saccharomyces cerevisiae pex5 mutant restored protein translocation into peroxisomes. These experiments confirmed the identity of the tobacco protein as a PTS1 receptor and indicated that components of the peroxisomal translocation apparatus are conserved functionally. Two-hybrid assays showed that NtPEX5 interacts with a wide range of PTS1 variants that also interact with the human Pex5p. Interestingly, the C-terminal residues of some of these peptides deviated from the established plant PTS1 consensus sequence. We conclude that there are significant sequence and functional similarities between the plant and human Pex5ps

• Publisher: National Academy of Sciences of the United States of America,National Acad Sciences,National Academy of Sciences,The National Academy of Sciences
• Subject: ADN / Amino Acid Sequence / AMINO ACID SEQUENCES / Amino acids / Animals / B lymphocytes / BINDING PROTEINS / BINDING SITES / Biological Sciences / Biology / Botany / CELL MEMBRANES / CHEMICAL COMPOSITION / chemistry / Cloning, Molecular / COMPARISONS / COMPLEMENTARY DNA / COMPLEMENTATION / COMPOSICION QUIMICA / COMPOSITION CHIMIQUE / CYTOPLASMIC ORGANELLES / DNA / Escherichia coli / Escherichia coli - genetics / GENBANK/AF053104 / GENBANK/AF056282 / GENBANK/AF056283 / GENERO HUMANO / genetic complementation / GENETIC TRANSFORMATION / GENETICA / GENETICS / GENETIQUE / GENRE HUMAIN / Humans / Mammals / MANKIND / MEMBRANAS CELULARES / MEMBRANE CELLULAIRE / metabolism / METABOLISME DES PROTEINES / METABOLISMO PROTEICO / MOLECULAR SEQUENCE DATA / MUTANT / MUTANTES / MUTANTS / Nicotiana - genetics / Nicotiana - metabolism / NICOTIANA TABACUM / NUCLEOTIDE SEQUENCE / nucleotide sequences / ORGANITE CELLULAIRE / ORGANULOS CITOPLASMICOS / Peptide Fragments / Peptide Fragments - chemistry / Peptide Fragments - metabolism / Peroxisome-Targeting Signal 1 Receptor / PEROXISOMES / PLANT PROTEINS / Plants / Plants, Toxic / Plasmids / PROTEIN METABOLISM / PROTEIN TRANSPORT / PROTEINAS / PROTEINAS AGLUTINANTES / PROTEINE / PROTEINE DE LIAISON / PROTEINS / Receptors / Receptors, Cytoplasmic and Nuclear / Receptors, Cytoplasmic and Nuclear - chemistry / Receptors, Cytoplasmic and Nuclear - genetics / Receptors, Cytoplasmic and Nuclear - metabolism / Recombinant Proteins / Recombinant Proteins - chemistry / Recombinant Proteins - metabolism / SACCHAROMYCES CEREVISIAE / Saccharomyces cerevisiae - genetics / SECUENCIA NUCLEOTIDICA / Sequence Alignment / Sequence Homology, Amino Acid / SEQUENCE NUCLEOTIDIQUE / SIGNAL PEPTIDE / Tobacco / TRANSFORMACION GENETICA / TRANSFORMATION GENETIQUE / Translocation / Yeasts