Immunolocalization of mannitol dehydrogenase in celery plants and cells.

AUTOR(ES)

Zamski, E

RESUMO

Immunolocalization of mannitol dehydrogenase (MTD) in celery (Apium graveolens L.) suspension cells and plants showed that MTD is a cytoplasmic enzyme. MTD was found in the meristems of celery root apices, in young expanding leaves, in the vascular cambium, and in the phloem, including sieve-element/companion cell complexes, parenchyma, and in the exuding phloem sap of cut petioles. Suspension cells that were grown in medium with mannitol as the sole carbon source showed a high anti-MTD cross-reaction in the cytoplasm, whereas cells that were grown in sucrose-containing medium showed little or no cross-reaction. Gel-blot analysis of proteins from vascular and nonvascular tissues of mature celery petioles showed a strong anti-MTD sera cross-reactive band, corresponding to the 40-kD molecular mass of MTD in vascular extracts, but no cross-reactive bands in nonvascular extracts. The distribution pattern of MTD within celery plants and in cell cultures that were grown on different carbon sources is consistent with the hypothesis that the Mtd gene may be regulated by sugar repression. Additionally, a developmental component may regulate the distribution of MTD within celery plants.

Documentos Relacionados

• Sugar Repression of Mannitol Dehydrogenase Activity in Celery Cells.
• Purification of NAD-dependent mannitol dehydrogenase from celery suspension cultures.
• Subcellular localization of celery mannitol dehydrogenase. A cytosolic metabolic enzyme in nuclei.
• NADPH Supply and Mannitol Biosynthesis. Characterization, Cloning, and Regulation of the Non-Reversible Glyceraldehyde-3-Phosphate Dehydrogenase in Celery Leaves1
• Mannitol Metabolism in Celery Stressed by Excess Macronutrients.