Abstract:
:Zeatin is the most active and ubiquitous of the naturally occurring cytokinins. The O-glucoside of zeatin, found in all plants examined, is considered to be important in cytokinin transport, storage, and protection against cytokinin oxidases. The enzyme UDPglucose:zeatin O-glucosyltransferase (EC 2.4.1.203) was previously isolated from Phaseolus lunatus seeds. Immunoscreening of an expression library with monospecific antibody resulted in the isolation of a cDNA encoding the enzyme. The recombinant protein efficiently converts labeled zeatin to O-glucosylzeatin and has properties similar to the native enzyme. The cDNA of 1.5 kb contains an ORF encoding a 51. 4-kDa polypeptide of 459 amino acids. The sequence is unique based on a BLAST search of data bases. The genomic sequence, isolated with PCR using specific primers based on the cDNA sequence, does not contain introns. The cloning of this gene provides the tools for further study of the regulation of cytokinin metabolism and analysis of the precise role of O-glucosylzeatin in plant development.
journal_name
Proc Natl Acad Sci U S Aauthors
Martin RC,Mok MC,Mok DWdoi
10.1073/pnas.96.1.284subject
Has Abstractpub_date
1999-01-05 00:00:00pages
284-9issue
1eissn
0027-8424issn
1091-6490journal_volume
96pub_type
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