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. 1981 Jan;67(1):156–162. doi: 10.1104/pp.67.1.156

Purification and Properties of a Protein Which Binds Cytokinin-active 6-Substituted Purines 1

Jack L Erion 1,2,2, J Eugene Fox 1,2,3
PMCID: PMC425641  PMID: 16661618

Abstract

A protein which binds 6-substituted purines of the cytokinin type with relatively high affinity has been extensively purified from wheat germ. Conventional chromatographic techniques, as well as an affinity matrix to which a cytokinin was covalently coupled, were used in the purification. The wheat germ cytokinin-binding protein (CBF-1) has four unlike subunits and an apparent molecular weight of 183,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis.

CBF-1 is saturated at one cytokinin molecule per tetramer with a Kd for 6-benzylaminopurine of 5 × 10−7 molar. The protein exists both on the native wheat germ ribosome (1 molecule CBF-1 per 80S ribosome) and free in the cytosol with approximately three copies of the latter for each of the former. Data from affinity chromatography studies and cross-linking experiments strongly suggest that a specific binding site for CBF-1 occurs on the wheat germ ribosome.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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