Organ-specific distribution and subcellular localisation of ascorbate peroxidase isoenzymes in potato (Solanum tuberosum L.) plants

• Tipo: Artigo em Revista Científica Internacional
• Data: 2005

Autores

Pereira, CS (Autor) Outra; da Costa, DS (Autor) FCUP; Teixeira, J (Autor) FCUP; Pereira, S (Autor) FCUP

Revista

Título: Protoplasma

Vol. 226

Páginas: 223-230

ISSN: 0033-183X

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 7 Citações

Scopus - 5 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Ciências biológicas

Outras Informações

ID Authenticus: P-000-0CX

DOI: 10.1007/s00709-005-0120-8

Abstract (EN): Ascorbate peroxidase (EC 1.11.1.11), a heme-containing homodimeric protein, is a hydrogen peroxide-scavenging enzyme, playing an important role in plants in order to protect them from oxidative stress, thus adverting cellular damage. Several ascorbate peroxidase isoenzymes have been reported but the understanding of their physiological role still depends on a better knowledge of their precise localisation within plant organs. Immunocytochemistry techniques were performed in order to elucidate the peroxisomal and cytosolic ascorbate peroxidase distribution within tissues of leaves and sprouts of potato plants. The peroxisomal isoenzyme was found to have a broad distribution in sprouts, but a differential one in leaves, being restricted to the spongy parenchyma. This differential expression may be associated to the mesophyll asymmetry and the diverse physiological processes that occur in it. The cytosolic isoenzyme was not detected in leaves under the used conditions, probably because it is present in low amounts in these tissues. The results obtained in sprouts were at least curious: cytosolic ascorbate was found to be adjacent to the amyloplasts. Given these results, it is possible to state that apart from their similarity, these two isoenzymes reside in different organelles and seem to take part in different physiological processes as suggested by their organ- and tissue-specific distribution.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 8