Synthesis and secretion of tobacco neutral PR-5 protein by transgenic tobacco and yeast.
Tobacco neutral osmotin-like protein was expressed in both homologous and heterologous expression systems. Osmotin-like protein was retained in tobacco cells when expressed as the prepro-form, whereas deletion of the carboxyl-terminal propeptide of 22 amino acids induced its secretion into the extracellular fluid. Without the amino-terminal signal peptide, there was no accumulation of osmotin-like protein. When the construct with both the amino- and carboxyl-terminal peptides was introduced to methylotrophic yeast, divergent osmotin-like protein forms were found in the cell and medium. Results suggest that the amino-terminal signal of the osmotin-like protein is essential for the transport of protein to the endoplasmic reticulum both in tobacco and yeasts but that the carboxyl-terminal propeptide signal is effective only for intracellular retention in tobacco.
Sato
F
F
Department of Agricultural Chemistry, Faculty of Agriculture, Kyoto University, Japan.
Koiwa
H
H
Sakai
Y
Y
Kato
N
N
Yamada
Y
Y
D000595:Amino Acid Sequence; D001483:Base Sequence; D001692:Biological Transport; D002175:Candida / Q000235:genetics; D005822:Genetic Vectors; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D010947:Plants, Toxic; D011498:Protein Precursors / Q000096:biosynthesis; D021382:Protein Sorting Signals; D014026:Nicotiana / Q000235:genetics*; D014170:Transformation, Genetic
D010940:Plant Proteins; D011498:Protein Precursors; D021382:Protein Sorting Signals; C053376:pathogenesis-related proteins, plant; C073139:osmotin protein, Nicotiana tabacum