The secretory nature of the lesion of carrot cell variant ts11, rescuable by endochitinase.
Planta
; 203(3): 381-9, 1997.
Article
em En
| MEDLINE
| ID: mdl-9431685
ABSTRACT
The carrot cell variant ts11 is unable to form somatic embryos at the non-permissive temperature of 32 degrees C, but the block can be overcome by the addition of a 32-kDa acidic endochitinase to the medium. In this work we conducted a cyto-histological analysis of the blocked embryo forms. The morphology of the endomembrane system is altered; in particular, the ER is dilated and may show electron-dense precipitates and continuity with the plasma membrane. These morphological alterations do not occur in the presence of externally-added endochitinase. We also noticed modifications of the culture medium that are probably related to the morphological observations the total amount of secreted proteins is reduced and pulse-chase experiments revealed that, compared with wild-type cells, the secretion of major polypeptides is reduced while new minor polypeptides are secreted. Western blot analysis revealed the presence of the binding protein BiP, a resident of the ER and of glutamine synthase, a cytosolic protein, in the medium of ts11 but not wild-type cells. These results indicate that ts11 is altered in the secretory pathway but do not clarify the role of endochitinase.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sementes
/
Quitinases
/
Daucus carota
Idioma:
En
Revista:
Planta
Ano de publicação:
1997
Tipo de documento:
Article