IMMUNOCYTOLOCALIZATION OF GLUTAMINE-SYNTHETASE IN MESOPHYLL AND PHLOEM OF LEAVES OF SOLANUM-TUBEROSUM L

• Tipo: Artigo em Revista Científica Internacional
• Data: 1992

Autores

PEREIRA, S (Autor) FCUP; CARVALHO, H (Autor) REIT; SUNKEL, C (Autor) ICBAS; SALEMA, R (Autor) FCUP

Revista

Título: Protoplasma

Vol. 167

Páginas: 66-73

ISSN: 0033-183X

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 51 Citações

Scopus - 52 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Ciências biológicas

Outras Informações

ID Authenticus: P-001-Q5T

DOI: 10.1007/bf01353582

Abstract (EN): Localization of glutamine synthetase in Solanum tuberosum leaves was investigated by techniques of Western tissue printing and immunogold electron microscopy. Anti-GS antibodies used in immunolocalization recognize two peptides (45 kDa and 42 kDa) on Western blots. Antibody stained tissue prints on nitrocellulose membranes allowed low resolution localization of GS. Immunostaining was most evident in the adaxial phloem of the leaf midribs and petiole veins. High-resolution localization of glutamine synthetase by immunogold electron microscopy revealed that this enzyme occurs in both the chloroplasts and the cytosol of S. tuberosum leaf cells. However, GS was specifically associated with the chloroplasts of mesophyll cells and with the cytoplasm of phloem companion cells. The evidence for cell-specific localization of chloroplast and cytosolic GS presented here agrees with the recently reported cell-specific pattern of expression of GUS reporter gene, directed by promoters for chloroplast and cytosolic GS form in tobacco transgenic plants. These data provide additional clues to the interpretation of the functional role of these different isoenzymes and its relationship with their specific localization.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 8