Cytokinin induces a rapid decrease in the levels of mRNAs for catalase, 3-hydroxy-3-methylglutaryl CoA reductase, lectin and other unidentified proteins in etiolated cotyledons of cucumber.
Large-scale differential hybridization was performed to examine rapid changes in gene expression caused by a phytohormone, cytokinin, in etiolated cotyledons of cucumber (Cucumis sativus L.). We isolated 86 cDNA clones for mRNAs whose levels decreased within 2 h of the start of treatment with N6-benzyladenine (BA). Partial nucleotide sequences showed that some of the cDNAs were homologous to those for catalase, 3-hydroxy-3-methylglutaryl CoA reductase (HMGR) and a lectin. This is the first report that the levels of the mRNAs for those proteins are regulated by a cytokinin in darkness. Together with previous results [Teramoto et al. (1993) Physiol. Plant. 87: 584, (1994) Planta 193: 573, (1995) Planta 196: 387], the present study suggests that the cytokinin act to lower the levels of mRNAs transcribed from various genes in etiolated cotyledons.
Toyama
T
T
Department of Botany, Faculty of Science, Kyoto University, Japan.
Teramoto
H
H
Takeba
G
G
Tsuji
H
H
D000225:Adenine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000595:Amino Acid Sequence; D001483:Base Sequence; D001593:Benzyl Compounds; D002374:Catalase / Q000235:genetics; D018548:Cotyledon / Q000378:metabolism; D018553:Cucumis sativus / Q000235:genetics*; D003583:Cytokinins / Q000494:pharmacology*; D018076:DNA, Complementary; D018744:DNA, Plant; D018506:Gene Expression Regulation, Plant; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics; D007701:Kinetin; D037102:Lectins / Q000235:genetics; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D010937:Plant Growth Regulators / Q000494:pharmacology*; D037121:Plant Lectins; D010940:Plant Proteins / Q000235:genetics*; D011687:Purines; D012333:RNA, Messenger / Q000378:metabolism*; D018749:RNA, Plant / Q000378:metabolism
D001593:Benzyl Compounds; D003583:Cytokinins; D018076:DNA, Complementary; D018744:DNA, Plant; D037102:Lectins; D010937:Plant Growth Regulators; D037121:Plant Lectins; D010940:Plant Proteins; D011687:Purines; D012333:RNA, Messenger; D018749:RNA, Plant; D006903:Hydroxymethylglutaryl CoA Reductases; D002374:Catalase; D000225:Adenine; C480551:benzylaminopurine; D007701:Kinetin