title: Proline-rich cell wall proteins accumulate in growing regions and phloem tissue in response to water deficit in common bean seedlings.
abstract: Plant cell walls undergo dynamic changes in response to different environmental stress conditions. In response to water deficit, two related proline-rich glycoproteins, called p33 and p36, accumulate in the soluble fraction of the cell walls in Phaseolus vulgaris (Covarrubias et al. in Plant Physiol 107:1119-1128, 1995). In this work, we show that p33 and p36 are able to form a 240 kDa oligomer, which is found in the cell wall soluble fraction. We present evidence indicating that the highest accumulation of these proteins in response to water deficit occurs in the growing regions of common bean seedlings, particularly in the phloem tissues. These proteins were detected in P. vulgaris cell suspension cultures, where the p33/p36 ratio was higher under hyperosmotic conditions than in bean seedlings subjected to the same treatment. The results support a role for these proteins during the plant cell response to changes in its water status, and suggest that cell wall modifications are induced in active growing cells of common bean in response to water limitation.
authors.affiliation: Departamento de Biología Molecular de Plantas, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Apdo. Postal 510-3, 62250 Cuernavaca, Morelos, Mexico.
authors.forename: Marina
authors.initials: M
authors.lastname: Battaglia
authors.forename: Rosa M
authors.initials: RM
authors.lastname: Solórzano
authors.forename: Magdalena
authors.initials: M
authors.lastname: Hernández
authors.forename: Sonia
authors.initials: S
authors.lastname: Cuéllar-Ortiz
authors.forename: Blanca
authors.initials: B
authors.lastname: García-Gómez
authors.forename: Judith
authors.initials: J
authors.lastname: Márquez
authors.forename: Alejandra A
authors.initials: AA
authors.lastname: Covarrubias
mesh_terms: D002473:Cell Wall / Q000378:metabolism*; D002478:Cells, Cultured; D004591:Electrophoresis, Polyacrylamide Gel; D027805:Phaseolus / Q000166:cytology / Q000254:growth & development / Q000378:metabolism*; D052585:Phloem / Q000502:physiology*; D010940:Plant Proteins / Q000302:isolation & purification / Q000378:metabolism*; D011392:Proline / Q000378:metabolism*; D014867:Water / Q000378:metabolism*; D014881:Water Supply
chemical_list: D010940:Plant Proteins; D014867:Water; D011392:Proline