Evidence for sugar signalling in the regulation of asparagine synthetase gene expressed in Phaseolus vulgaris roots and nodules
Por:
Silvente, S, Reddy, PM, Khandual, S, Blanco, L, Alvarado-Affantranger, X, Sanchez, F, Lara-Flores, M
Publicada:
1 abr 2008
Resumen:
A cDNA clone, designated as PvNAS2, encoding asparagine amidotransferase (asparagine synthetase) was isolated from nodule tissue of common bean (Phaseolus vulgaris cv. Negro Jamapa). Southern blot analysis indicated that asparagine synthetase in bean is encoded by a small gene family. Northern analysis of RNAs from various plant organs demonstrated that PvNAS2 is highly expressed in roots, followed by nodules in which it is mainly induced during the early days of nitrogen fixation. Investigations with the PvNAS2 promoter gusA fusion revealed that the expression of PvNAS2 in roots is confined to vascular bundles and meristematic tissues, while in root nodules its expression is solely localized to vascular traces and outer cortical cells encompassing the central nitrogen-fixing zone, but never detected in either infected or non-infected cells located in the central region of the nodule. PvNAS2 is down-regulated when carbon availability is reduced in nodules, and the addition of sugars to
Filiaciones:
Silvente, S:
Univ Nacl Autonoma Mexico, Ctr Ciencias Genom, Cuernavaca 62210, Morelos, Mexico
Reddy, PM:
Univ Nacl Autonoma Mexico, Ctr Ciencias Genom, Cuernavaca 62210, Morelos, Mexico
Khandual, S:
Univ Nacl Autonoma Mexico, Ctr Ciencias Genom, Cuernavaca 62210, Morelos, Mexico
Blanco, L:
Univ Nacl Autonoma Mexico, Ctr Ciencias Genom, Cuernavaca 62210, Morelos, Mexico
Alvarado-Affantranger, X:
Univ Nacl Autonoma Mexico, Inst Biotechnol, Cuernavaca 62210, Morelos, Mexico
Sanchez, F:
Univ Nacl Autonoma Mexico, Inst Biotechnol, Cuernavaca 62210, Morelos, Mexico
Lara-Flores, M:
Univ Nacl Autonoma Mexico, Ctr Ciencias Genom, Cuernavaca 62210, Morelos, Mexico
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