Plant Growth Regulation

, Volume 9, Issue 1, pp 9–17 | Cite as

Isolation and characterization of a cytokinin-binding protein from cucumber cotyledons

  • Chellathai Jayabaskaran


A protein which binds specifically to [3H]-zeatin has been isolated from cucumber cotyledons by chromatographic techniques. Its binding to [3H]-zeatin was inhibited remarkably by the addition of non-radioactive cytokinins and the order of inhibition was zeatin > -zeatin riboside > N6-(Δ2-isopentenyl)adenine > N6-(Δ2-isopentenyl)adenosine > N6-benzyl-adenosine > kinetin riboside. This protein behaved as a soluble protein with an apparent molecular size of 43,000 daltons on gel filtration through calibrated Sephadex G-100 column. The dissociation constant, Kd, of the protein-zeatin complex was about 4 × 10−7 M.

Key words

Cucumis sativus binding protein cytokinins and specificity 


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Copyright information

© Kluwer Academic Publishers 1990

Authors and Affiliations

  • Chellathai Jayabaskaran
    • 1
  1. 1.Department of BiochemistryIndian Institute of ScienceBangaloreIndia

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