Cloning of a cDNA encoding a plasma membrane-associated, uronide binding phosphoprotein with physical properties similar to viral movement proteins.
Oligogalacturonides are structural and regulatory homopolymers from the extracellular pectic matrix of plants. In vitro micromolar concentrations of oligogalacturonates and polygalacturonates were shown previously to stimulate the phosphorylation of a small plasma membrane-associated protein in potato. Immunologically cross-reactive proteins were detected in plasma membrane-enriched fractions from all angiosperm subclasses in the Cronquist system. Polygalacturonate-enhanced phosphorylation of the protein was observed in four of the six dicotyledon subclasses but not in any of the five monocotyledon subclasses. A cDNA for the protein was cloned from potato. The deduced protein is extremely hydrophilic and has a proline-rich N terminus. The C-terminal half of the protein was predicted to be a coiled coil, suggesting that the protein interacts with other macromolecules. The recombinant protein was found to bind both simple and complex galacturonides. The behavior of the protein suggests several parallels with viral proteins involved in intercellular communication.
Reymond
P
P
Institut de Biologie et de Physiologie Végétales, Université de Lausanne, Switzerland.
Kunz
B
B
Paul-Pletzer
K
K
Grimm
R
R
Eckerskorn
C
C
Farmer
E E
EE
D000595:Amino Acid Sequence; D001483:Base Sequence; D002352:Carrier Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary; D005685:Galactans / Q000378:metabolism; D006603:Hexuronic Acids / Q000378:metabolism; D008969:Molecular Sequence Data; D010368:Pectins / Q000378:metabolism; D010750:Phosphoproteins / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism*; D010940:Plant Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000378:metabolism*; D053830:Plant Viral Movement Proteins; D010944:Plants / Q000378:metabolism*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D011198:Solanum tuberosum / Q000378:metabolism; D014764:Viral Proteins / Q000737:chemistry
D002352:Carrier Proteins; D018076:DNA, Complementary; D005685:Galactans; D006603:Hexuronic Acids; D010750:Phosphoproteins; D010940:Plant Proteins; D053830:Plant Viral Movement Proteins; D011994:Recombinant Proteins; D014764:Viral Proteins; C103794:remorin; D010368:Pectins; C003181:polygalacturonic acid