文章基本信息

标题：A maize cytokinin gene encoding an O-glucosyltransferase specific to cis-zeatin
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作者：Ruth C. Martin ; Machteld C. Mok ; Jeffrey E. Habben 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2001
卷号：98
期号：10
页码：5922-5926
DOI：10.1073/pnas.101128798
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Zeatin is a naturally occurring cytokinin. Biosynthesis and metabolism studies of zeatin have been directed mostly at the trans isomer, although cis-zeatin and its riboside occur as major components in some plant species. It is not known whether parallel regulatory pathways exist for the two isomers. Based on the sequence of the gene ZOG1 encoding a trans-zeatin O-glucosyltransferase from Phaseolus (EC 2.4.1.203), a cis-zeatin-specific O-glucosyltransferase was isolated from maize. This gene, cisZOG1, contains an ORF of 1,401 nucleotides encoding a protein of 51.1 kDa with 41% identity to the Phaseolus ZOG1 protein. Unexpectedly, the maize enzyme recognizes as substrates cis-zeatin and UDP-glucose but not cis-ribosylzeatin, trans-zeatin, or trans-ribosylzeatin. This finding indicates the existence of cis-specific regulatory elements in plants and suggests that cis-zeatin and derivatives may be more important in cytokinin homeostasis than currently recognized.