Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 Apr 30;21(5):576.
doi: 10.3390/molecules21050576.

Synthesis of a Cytokinin Linked by a Spacer to Dexamethasone and Biotin: Conjugates to Detect Cytokinin-Binding Proteins

You Wang  1 , David S Letham  2 , Peter C L John  3 , Ren Zhang  4
Affiliations

Synthesis of a Cytokinin Linked by a Spacer to Dexamethasone and Biotin: Conjugates to Detect Cytokinin-Binding Proteins

You Wang et al. Molecules. .

Abstract

Yeast cells expressing cDNA libraries have provided two new approaches to facilitate further identification of cytokinin-binding proteins and receptors. These are the yeast three hybrid (Y3H) system and fluorescence activated cell sorting (FACS). The Y3H system requires a synthetic hybrid ligand comprising an "anchor" moiety (e.g., dexamethasone) linked to a cytokinin via a spacer. In the yeast nucleus, this ligand by binding connects two fusion proteins leading to a reporter gene activation and detection and characterisation of cytokinin binding proteins. Herein is reported the first synthesis of dexamethasone-cytokinin ligands with a spacer linkage. This was attached to the purine ring of 6-benzylaminopurine (BAP) at positions 2, 8 or 9. To achieve this, dexamethasone was modified by periodate oxidation yielding a carboxylic group used for conjugation to the spacer by amide formation. Biotinyl derivatives of cytokinins for FACS included those synthesised by reaction of an activated ester of biotin with 8-(10-amino-decylamino) derivatives of BAP and BAP 9-riboside. Properties of the conjugates and some biological situations where they could be applicable are discussed briefly.

Keywords: 6-benzylaminopurine (BAP); BAP-biotin conjugates; BAP-dexamethasone conjugates; cytokinin-binding proteins; yeast three hybrid.

PubMed Disclaimer

Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Structures of compounds used and synthesised in this study.
Figure 1
Figure 1
Structures of compounds used and synthesised in this study.
Figure 2
Figure 2
The sequence of reactions used to synthesise BAP-dexamethasone conjugates with purine ring linkage at C-8 (5b, 6b) or N-9 (4b). (A) 8-bromoadenosine; (B) 1-benzyl-8-bromoadenosine; (C) 6-benzylamino-8-bromopurine 9-riboside; (D) 6-benzylamino-9-benzyl-8-bromopurine; (E) 6-benzylaminopurin; (F) ethyl 3-(6-benzylaminopurine-9-yl)propionate. The reactions are: (i) benzylbromide in DMF at 37 °C; (ii) 0.25 M NH4OH at 37 °C; (iii) 1,10-diaminodecan in n-PrOH at 100 °C; (iv) methanolysis with HCl at 37 °C; (v) activated ester of “dexamethasone acid” at 23 °C; (vi) ethyl acrylate/NaOEt; (vii) 1,10-diaminodecane in toluene at 110 °C.
See this image and copyright information in PMC

References

    1. Kaminek M. Tracking the story of cytokinin research. J. Plant Growth Regul. 2015;34:723–739. doi: 10.1007/s00344-015-9543-4. - DOI
    1. Stolz A., Riefler M., Lomin S.N., Achazi K., Romanov G.A., Schmülling T. The specificity of cytokinin signalling in Arabidopsis thaliana is mediated by differing ligand affinities and expression profiles of the receptors. Plant J. 2011;67:157–168. doi: 10.1111/j.1365-313X.2011.04584.x. - DOI - PubMed
    1. Wulfetange K., Lomin S.N., Romanov G.A., Stolz A., Heyl A., Schmülling T. The cytokinin receptors of Arabidopsis are located mainly to the endoplasmic reticulum. Plant Physiol. 2011;156:1808–1018. doi: 10.1104/pp.111.180539. - DOI - PMC - PubMed
    1. Murray J.D., Karas B.J., Sato S., Tabata S., Amyot L., Szczyglowski K.A. Cytokinin perception mutant colonized by Rhizobium in the absence of nodule organogenesis. Science. 2007;315:101–104. doi: 10.1126/science.1132514. - DOI - PubMed
    1. Dolezal K., Popa I., Krystof V., Spichal L., Fojtikova M., Holub J., Lenobel R., Schmülling T., Strnad M. Preparation and biological activity of 6-benzylaminopurine derivatives in plants and human cancer cells. Bioorg. Med. Chem. 2006;14:875–884. doi: 10.1016/j.bmc.2005.09.004. - DOI - PubMed

LinkOut - more resources