The extensin signal peptide allows secretion of a heterologous protein from protoplasts.
Extensins are hydroxyproline-rich glycoproteins which are amongst the most abundant proteins present in the cell wall of higher plants. Here, we describe the structural analysis of an extensin-encoding gene from Nicotiana plumbaginifolia. The encoded protein (46 kDa) has a highly repetitive structure and contains 37% proline, 18.1% tyrosine, 13.4% lysine, 8.1% serine and 7.1% histidine. The extensin-encoding sequence contains a typical signal peptide for translocation of the protein to the endoplasmic reticulum. By using chimeric genes consisting of different 5' parts of the extensin-encoding gene and the neomycin phosphotransferase II-encoding gene (nptII) as reporter gene, we show that the N-terminal part of extensin can mediate the secretion of NPTII from electroporated N. tabacum protoplasts.
De Loose
M
M
Laboratorium voor Genetica Rijksuniversiteit Gent, Belgium.
Gheysen
G
G
Tiré
C
C
Gielen
J
J
Villarroel
R
R
Genetello
C
C
Van Montagu
M
M
Depicker
A
A
Inzé
D
D
D000595:Amino Acid Sequence; D001483:Base Sequence; D017343:Genes, Plant; D006023:Glycoproteins / Q000235:genetics*; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics*; D010947:Plants, Toxic; D011487:Protein Conformation; D021382:Protein Sorting Signals / Q000235:genetics*; D011523:Protoplasts / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid; D015183:Restriction Mapping; D014026:Nicotiana / Q000235:genetics* / Q000378:metabolism
D006023:Glycoproteins; D010940:Plant Proteins; D021382:Protein Sorting Signals; C005488:extensin protein, plant