Partition of radiolabeled amino acids in detached wheat heads in culture

Conference · Tue May 01 04:00:00 EDT 1990 · Plant Physiology, Supplement; (USA)

OSTI ID:5628205

Inwood, W; Bernardin, J ^[1]

---

1. USDA, Albany, CA (USA)

The concentration of a particular amino acid supplied to a detached wheat head affected the ultimate distribution of that amino acid among the tissues of the head. Detached wheat heads (Triticum aestivum L. cv Cheyenne) were supplied with a pulse of ({sup 3}H)leucine in the culture medium and were chased with medium that contained glutamine as the sole nitrogen source. When the amount of radiolabel was held constant, an increasing concentration of unlabeled leucine in the pulse medium led to an increased partition of the radiolabel into the grain tissues of the head. When the concentration of unlabeled leucine was increased from zero to radiolabeled leucine was partitioned to endosperm tissue and twice as much to seedcoat tissues. An effect of amino acid concentration on radiolabel partition was also found for methionine and proline, but the effect was not as dramatic. These results suggest the existence of an amino acid transport system between the transpiration stream of the wheat head and the grain that exhibits cooperative kinetics or amino acid activation.

• OSTI ID: 5628205
• Report Number(s): CONF-9007196--
• Conference Information: Journal Name: Plant Physiology, Supplement; (USA) Journal Volume: 93:1
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
BIOCHEMICAL REACTION KINETICS
CARBOXYLIC ACIDS
CEREALS
GRAMINEAE
HYDROGEN COMPOUNDS
ISOTOPE APPLICATIONS
KINETICS
LILIOPSIDA
MAGNOLIOPHYTA
ORGANIC ACIDS
ORGANIC COMPOUNDS
PLANTS
REACTION KINETICS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
WHEAT