In vitro gibberellin A/sub 1/ binding in Zea mays L

Journal Article · Tue Dec 01 00:00:00 EST 1987 · Plant Physiol.; (United States)

OSTI ID:5403467

Keith, B; Rappaport, L

The first and second leaf sheaths of Zea mays L. cv Golden Jubilee were extracted and the extract centrifuged at 100,000g to yield a supernatant or cytosol fraction. Binding of (/sup 3/H)gibberellin A/sub 1/ (GA/sub 1/) to a soluble macromolecular component present in the cytosol was demonstrated at 4/sup 0/C by Sephadex G-200 chromatography. The binding component was of high molecular weight (HMW) and greater than 500 kilodaltons. The HMW component was shown to be a protein and the /sup 3/H-activity bound to this protein was largely (/sup 3/H)GA/sub 1/ and not a metabolite. Binding was pH sensitive but only a small percentage (20%) appeared to be exchangeable on addition of unlabeled GA/sub 1/. Both biologically active and inactive GAs and non-GAs were able to inhibit GA/sub 1/ binding. (/sup 3/H)GA/sub 1/ binding to an intermediate molecular weight (IMW) fraction (40-100 kilodaltons) was also detected, provided cytosol was first desalted using Sephadex G-200 chromatography. Gel filtration studies suggest that the HMW binding component is an aggregate derived from the IMW fraction. The HMW binding fraction can be separated into two components using anion exchange chromatography.

• Research Organization: Univ. of California, Davis
• OSTI ID: 5403467
• Journal Information: Plant Physiol.; (United States), Vol. 85:4
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
PROTEINS
BIOCHEMICAL REACTION KINETICS
IN VITRO
ION EXCHANGE CHROMATOGRAPHY
MAIZE
MOLECULAR WEIGHT
TRACER TECHNIQUES
TRITIUM COMPOUNDS
CEREALS
CHROMATOGRAPHY
GRASS
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
ORGANIC COMPOUNDS
PLANTS
REACTION KINETICS
SEPARATION PROCESSES
550201* - Biochemistry- Tracer Techniques