[Molecular identification of cytokinin-specific binding protein].
Synthetic phenylurea derivatives such as N-phenyl-N'-(4-pyridyl)urea (4PU) and N-(2-chloro-4-pyridyl)-N'-phenylurea (4PU30) have strong cytokinin activities. Using tritiated 4PU30 as a probe, we found the presence of a cytokinin-specific binding protein (CSBP) with high affinity for 4PU30 (Ka for 4PU30 = 4 x 10(10) M-1) in the soluble fraction of etiolated mung bean seedlings. We purified CSBP by the use of 4PU-Sepharose 4B, an affinity gel ligated with 4PU. Analysis of its cDNA revealed that CSBP was a novel member of a major pollen allergen/pathogenesis-related protein family with a calculated molecular weight of 17 kDa. Recombinant CSBP was expressed in Escherichia coli was confirmed to bind specifically to cytokinins.
Fujimoto
Y
Y
Institute of Molecular and Cellular Biosciences, University of Tokyo, Japan.
Nagata
R
R
Kobayashi
H
H
Shudo
K
K
Hashimoto
Y
Y
D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry* / Q000302:isolation & purification; D003583:Cytokinins; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010671:Phenylurea Compounds / Q000378:metabolism; D010940:Plant Proteins / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism; D010944:Plants / Q000737:chemistry; D011485:Protein Binding; D011994:Recombinant Proteins
D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D003583:Cytokinins; D010671:Phenylurea Compounds; D010940:Plant Proteins; D011994:Recombinant Proteins; C053376:pathogenesis-related proteins, plant