Biomaterial Database

Cytokinin enhancement of the light induction of nitrate reductase transcript levels in etiolated barley leaves. 1990

J L Lu, and J R Ertl, and C M Chen

Department of Biological Sciences, University of Wisconsin-Parkside, Kenosha 53141.

To investigate the molecular mechanism of cytokinin regulation of nitrate reductase (NR) activity, the influence of benzyladenine (BA) on the level of NR transcript was studied in etiolated barley leaves using a barley NR cDNA as a probe. Northern blot analyses of the levels of NR poly (A)+ RNA indicate that the amount present is proportional to the concentration of BA (2 x 10(-8) to 2 x 10(-4) M) applied to the leaves. Enhancement of NR mRNA by 2 x 10(-5) M BA was clearly detected after 15 minutes of exposure of the leaves to light. The enhancement is cytokinin-specific and adenine is ineffective. Brief treatment with the protein synthesis inhibitor, cycloheximide, inhibited BA-enhanced NR activity but did not inhibit BA-enhanced NR transcript level, thus the enhancement was independent of concurrent protein synthesis. Nuclear runoff transcription studies showed that the enhancement of NR mRNA was at least partially due to increased transcription rates.

UI	MeSH Term	Description	Entries
D008027	Light	That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.	Light, Visible,Photoradiation,Radiation, Visible,Visible Radiation,Photoradiations,Radiations, Visible,Visible Light,Visible Radiations
D009565	Nitrate Reductases	Oxidoreductases that are specific for the reduction of NITRATES.	Reductases, Nitrate
D010944	Plants	Multicellular, eukaryotic life forms of kingdom Plantae. Plants acquired chloroplasts by direct endosymbiosis of CYANOBACTERIA. They are characterized by a mainly photosynthetic mode of nutrition; essentially unlimited growth at localized regions of cell divisions (MERISTEMS); cellulose within cells providing rigidity; the absence of organs of locomotion; absence of nervous and sensory systems; and an alternation of haploid and diploid generations. It is a non-taxonomical term most often referring to LAND PLANTS. In broad sense it includes RHODOPHYTA and GLAUCOPHYTA along with VIRIDIPLANTAE.	Plant
D003583	Cytokinins	Plant hormones that promote the separation of daughter cells after mitotic division of a parent cell. Frequently they are purine derivatives.	Cytokinin
D000225	Adenine	A purine base and a fundamental unit of ADENINE NUCLEOTIDES.	Vitamin B 4,4, Vitamin B,B 4, Vitamin
D001593	Benzyl Compounds	Benzene derivatives that contain a benzyl group with the general formula Phenyl-CH2-R.	Compounds, Benzyl
D012333	RNA, Messenger	RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.	Messenger RNA,Messenger RNA, Polyadenylated,Poly(A) Tail,Poly(A)+ RNA,Poly(A)+ mRNA,RNA, Messenger, Polyadenylated,RNA, Polyadenylated,mRNA,mRNA, Non-Polyadenylated,mRNA, Polyadenylated,Non-Polyadenylated mRNA,Poly(A) RNA,Polyadenylated mRNA,Non Polyadenylated mRNA,Polyadenylated Messenger RNA,Polyadenylated RNA,RNA, Polyadenylated Messenger,mRNA, Non Polyadenylated
D014158	Transcription, Genetic	The biosynthesis of RNA carried out on a template of DNA. The biosynthesis of DNA from an RNA template is called REVERSE TRANSCRIPTION.	Genetic Transcription
D015342	DNA Probes	Species- or subspecies-specific DNA (including COMPLEMENTARY DNA; conserved genes, whole chromosomes, or whole genomes) used in hybridization studies in order to identify microorganisms, to measure DNA-DNA homologies, to group subspecies, etc. The DNA probe hybridizes with a specific mRNA, if present. Conventional techniques used for testing for the hybridization product include dot blot assays, Southern blot assays, and DNA:RNA hybrid-specific antibody tests. Conventional labels for the DNA probe include the radioisotope labels 32P and 125I and the chemical label biotin. The use of DNA probes provides a specific, sensitive, rapid, and inexpensive replacement for cell culture techniques for diagnosing infections.	Chromosomal Probes,DNA Hybridization Probe,DNA Probe,Gene Probes, DNA,Conserved Gene Probes,DNA Hybridization Probes,Whole Chromosomal Probes,Whole Genomic DNA Probes,Chromosomal Probes, Whole,DNA Gene Probes,Gene Probes, Conserved,Hybridization Probe, DNA,Hybridization Probes, DNA,Probe, DNA,Probe, DNA Hybridization,Probes, Chromosomal,Probes, Conserved Gene,Probes, DNA,Probes, DNA Gene,Probes, DNA Hybridization,Probes, Whole Chromosomal
D050901	Nitrate Reductase	An enzyme that catalyzes the oxidation of nitrite to nitrate. It is a cytochrome protein that contains IRON and MOLYBDENUM.	Quinol-Nitrate Oxidoreductase,Respiratory Nitrate Reductase,Nitrate Reductase, Respiratory,Oxidoreductase, Quinol-Nitrate,Quinol Nitrate Oxidoreductase,Reductase, Nitrate,Reductase, Respiratory Nitrate