Modulation of the nitrate reductase transcript by cytokinin and abscisic acid in etiolated barley seedlings

Journal Article · Sat Apr 01 00:00:00 EST 1989 · Plant Physiology, Supplement; (USA)

OSTI ID:6868124

Lu, Jia-ling; Enl, J R; Chen, Chong-maw ^[1]

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1. Univ. of Wisconsin-Parkside, Kenosha (USA)

To investigate the molecular mechanism of the hormonal modulation of nitrate reductase (NR) activity, the influence of benzyladenine (BA) and/or abscisic acid (ABA) on the level of NR poly(A)RNA was studied in etiolated barley seedlings using a {sup 32}P-labelled NR cDNA as a probe. Enhancement of NR activity by 2 {times} 10{sup {minus}5}M BA was measurable only after 60 minutes of exposure of the seedlings to light, while a significant stimulatory effect on the transcript level could by clearly detected within 15 minutes. Northern blot analyses of the levels of NR poly(A)RNA indicate that the amount present is proportional to the concentration of BA applied to the seedlings. The stimulatory effects seen for BA were nullified by ABA. The counteractive effects of ABA on BA were dose-responsive, with greater inhibition at higher concentrations of ABA. Evidence suggests that the interaction of BA and ABA on NR activity is at the transcriptional level, however, is also possible that interactions occur at the postranscriptional level as well.

• OSTI ID: 6868124
• Journal Information: Plant Physiology, Supplement; (USA), Vol. 89:4; ISSN 0079-2241
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ABSCISIC ACID
BIOCHEMICAL REACTION KINETICS
KININS
OXIDOREDUCTASES
ENZYME ACTIVITY
BARLEY
PHOSPHORUS 32
RNA
SEEDLINGS
TRACER TECHNIQUES
TRANSCRIPTION
AUXINS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
CEREALS
DAYS LIVING RADIOISOTOPES
ENZYMES
GRASS
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LIGHT NUCLEI
LILIOPSIDA
MAGNOLIOPHYTA
MONOCARBOXYLIC ACIDS
NUCLEI
NUCLEIC ACIDS
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
PEPTIDES
PHOSPHORUS ISOTOPES
PLANT GROWTH REGULATORS
PLANTS
POLYPEPTIDES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
550201* - Biochemistry- Tracer Techniques