title: Transcriptional regulation of hydroxypyruvate reductase gene expression by cytokinin in etiolated pumpkin cotyledons.
abstract: To understand the mechanisms by which the expression of a specific gene is modulated by cytokinin, the regulation of hydroxypyruvate reductase (HPR) transcript levels by N6-benzyladenine (BA) in etiolated pumpkin (Cucurbita pepo L. cv. Halloween) cotyledons was investigated. A pumpkin HPR cDNA was generated by reverse transcriptase-polymerase chain reaction and its nucleotide sequence was determined. An antisense HPR RNA was prepared for RNase protection analysis of HPR-mRNA expression patterns in the cotyledons of dark-grown pumpkin seedlings. Treatment of the cotyledons with BA was shown to modulate HPR mRNA levels in a dose- and time-dependent manner. Similarly, nuclear run-on studies showed that the rate of transcription was also enhanced by BA treatment of the cotyledons. These results suggest that the enhancement of HPR mRNA by cytokinin is, at least in part, at the level of transcription.
authors.affiliation: Biomedical Research Institute, University of Wisconsin-Parkside, Kenosha 53141, USA.
authors.forename: B R
authors.initials: BR
authors.lastname: Andersen
authors.forename: G
authors.initials: G
authors.lastname: Jin
authors.forename: R
authors.initials: R
authors.lastname: Chen
authors.forename: J R
authors.initials: JR
authors.lastname: Ertl
authors.forename: C M
authors.initials: CM
authors.lastname: Chen
mesh_terms: D000225:Adenine / Q000031:analogs & derivatives* / Q000494:pharmacology; D000429:Alcohol Oxidoreductases / Q000096:biosynthesis* / Q000235:genetics; D000595:Amino Acid Sequence; D001483:Base Sequence; D001593:Benzyl Compounds; D018548:Cotyledon; D003583:Cytokinins / Q000494:pharmacology; D017931:DNA Primers; D018076:DNA, Complementary; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects*; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D017343:Genes, Plant; D050537:Hydroxypyruvate Reductase; D007701:Kinetin; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011687:Purines; D015347:RNA Probes; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic / Q000187:drug effects*; D014675:Vegetables / Q000201:enzymology* / Q000235:genetics
chemical_list: D001593:Benzyl Compounds; D003583:Cytokinins; D017931:DNA Primers; D018076:DNA, Complementary; D011687:Purines; D015347:RNA Probes; D012333:RNA, Messenger; D000429:Alcohol Oxidoreductases; D050537:Hydroxypyruvate Reductase; D000225:Adenine; C480551:benzylaminopurine; D007701:Kinetin