Proteólisis en plantas bajo condiciones de estrés producidas por metales
Plant proteolytic system includes proteases, mainly localized inside the organelles, and the ubiquitin-proteasome pathway in both, the cytoplasm and the nucleus. In cotyledons and leaves of sunflower plants treated with AlCl3, CoCl2, CuCl2, CrCl3, HgCl2, NiCl2, PbCl2 or ZnCl2 were produced for prote...
Guardado en:
| Autor principal: | |
|---|---|
| Otros Autores: | |
| Formato: | Tesis doctoral acceptedVersion |
| Lenguaje: | Español |
| Publicado: |
Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica
2009
|
| Materias: | |
| Acceso en línea: | http://repositoriouba.sisbi.uba.ar/gsdl/cgi-bin/library.cgi?a=d&c=posgraafa&cl=CL1&d=HWA_7823 https://repositoriouba.sisbi.uba.ar/gsdl/collect/posgraafa/index/assoc/HWA_7823.dir/7823.PDF |
| Aporte de: |
| Sumario: | Plant proteolytic system includes proteases, mainly localized inside the
organelles, and the ubiquitin-proteasome pathway in both, the cytoplasm and the
nucleus. In cotyledons and leaves of sunflower plants treated with AlCl3, CoCl2,
CuCl2, CrCl3, HgCl2, NiCl2, PbCl2 or ZnCl2 were produced for protein oxidative
damage. It is concluded that impairment of proteasome functionality and altered
proteases activities seem to be a common feature involved in metal phytotoxicity,
but heavy metal effects on proteolytic system cannot be generalized.
Particularly, cadmium increased protease specific activity in sunflower
cotyledons and leaves; nevertheless, this increase was not relevant enough to
avoid accumulation of oxidized proteins. Oxidation of proteins is one of the most
important effects of cadmium treatment. Leaves maize treatment with 50 -M
CdCl2 increased two of the three 20S proteasome activities. The incremental
changes in proteasome activities were probably caused by an increased level of
proteasome oxidation, with this being responsible for degradation of oxidized
proteins. Leaf treated with 100 -M CdCl2 decreased two 20S proteasome activities,
with a concomitant increase in accumulation of carbonylated and ubiquitinated
proteins. These results confirm evidence for the involvement of this proteolytic
system in cadmium-stressed plants. |
|---|