Detection of membrane-bound cytokinin-binding proteins in Arabidopsis thaliana cells.
Eur J Biochem
; 260(2): 512-9, 1999 Mar.
Article
en En
| MEDLINE
| ID: mdl-10095789
In order to isolate cytokinin-binding proteins (CBPs), we have developed new affinity probes constituted of a cytokinin such as zeatin riboside ([9R]Z) conjugated to a carrier protein. These probes were used for detecting CBPs in an ELISA procedure. The efficiency of the cytokinin conjugate in detecting CBPs was controlled with protein model: proteins having an affinity for cytokinin such as the monoclonal anti-[9R]Z antibodies did bind the cytokinin conjugate whereas proteins unable to bind cytokinin such as bovine serum albumin did not. Using these new affinity probes, we showed that CBPs are present in the membrane fraction of in vitro cultured Arabidopsis thaliana cells. The nature of the protein at the detected binding sites was demonstrated by submitting the microsomal proteins to a proteolytic treatment, which was found to eradicate the binding. Free biologically active cytokinins or monoclonal anti-[9R]Z antibodies inhibited the binding, thus showing the specificity of the interaction. The detected CBPs were partially solubilized from the membranes with potassium chloride, indicating their peripheral membrane location. The separation by anion exchange chromatography of solubilized microsomal proteins revealed the existence of two different CBPs. They were present at higher levels in cells during the exponential growth phase.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Proteínas de Plantas
/
Ensayo de Inmunoadsorción Enzimática
/
Proteínas Portadoras
/
Arabidopsis
/
Citocininas
/
Proteínas de Arabidopsis
Tipo de estudio:
Diagnostic_studies
Idioma:
En
Revista:
Eur J Biochem
Año:
1999
Tipo del documento:
Article
País de afiliación:
Francia
Pais de publicación:
Reino Unido