Selective turnover and alteration of soluble and cell wall polysaccharides in grasses

Conference · Wed May 01 00:00:00 EDT 1991 · Plant Physiology, Supplement; (United States)

OSTI ID:5601133

Gibeaut, D M; Carpita, N C ^[1]

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1. Purdue Univ., West Lafayette, IN (United States)

Cells of proso millet in liquid culture and leaves of maize seedlings readily incorporated radioactive glucose and arabinose into soluble and cell wall polymers. Radioactivity from arabinose accumulated selectively in polymers containing arabinose or xylose because a salvage pathway and C-4 epimerase yields both nucleotide-pentoses. On the other hand, radioactivity from glucose was found in all sugars and polymers. Pulse-chase experiments with proso millet cells in liquid culture demonstrated turnover of buffer soluble polymers within minutes and accumulation of radioactive polymers in the cell wall. In leaves of maize seedlings, radioactive polymers accumulated quickly and peaked 30 hours after the pulse, then decreased slowly for the remaining time course. During further growth of the seedling, radioactive polymers became more tenaciously bound in the cell wall. Sugars were constantly recycled from turnover of polysaccharides of the cell wall. Arabinose, hydrolyzed from glucuronoarabinoxylans, and glucose, hydrolyzed from mixed-linkage {beta}-D-glucans, constituted most of the sugar participating in turnover. Arabinogalactans were a large portion of the buffer soluble (cytoplasmic) polymers of both proso millet cells and maize seedling, and these polymers also exhibited turnover. Our results indicate that the primary cell wall is not simply a sink for various polysaccharide components, but rather a dynamic compartment exhibiting long-term re-organization by turnover and alteration of specific polymers during development.

• DOE Contract Number: FG02-88ER13903
• OSTI ID: 5601133
• Report Number(s): CONF-9107184-; CODEN: PPYSA
• Journal Information: Plant Physiology, Supplement; (United States), Vol. 96:1; Conference: Annual meeting of the American Society of Plant Physiology, Albuquerque, NM (United States), 28 Jul - 1 Aug 1991; ISSN 0079-2241
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
CELL WALL
PHYSIOLOGY
POLYSACCHARIDES
BIOCHEMICAL REACTION KINETICS
ARABINOSE
GRAMINEAE
LEAVES
MAIZE
PLANT CELLS
SEEDLINGS
XYLOSE
ALDEHYDES
CARBOHYDRATES
CELL CONSTITUENTS
CEREALS
KINETICS
LILIOPSIDA
MAGNOLIOPHYTA
MONOSACCHARIDES
ORGANIC COMPOUNDS
PENTOSES
PLANTS
REACTION KINETICS
SACCHARIDES
551000* - Physiological Systems