The Development of Glyoxysomes in Maize Scutellum: Changes in Morphology and Enzyme Compartmentation

AUTOR(ES)

Longo, Giovanna P.

RESUMO

Changes in the ultrastructural aspect of the glyoxysome fraction obtained from maize scutella by density gradient centrifugation were followed during the first 6 days of germination. During the first 2 days the fraction consists of very electron-dense bodies about 0.3 to 0.5 micron in size while at the 4th day it is formed by larger and less dense membrane-bound particles. Some intermediate form between the two types of organelles can be seen at the 3rd day. Between the 4th and the 6th days of germination the glyoxysomes are destroyed, and their enzymes are released into the cytosol. At the peak of their development (4th day) the glyoxysomes contain 75 to 80% of the total isocitratase and 65% of the total malate synthetase of the scutellum. These values drop to very low levels during the next 2 days. Catalase bound to glyoxysomes amounts to 30 to 35% of the total activity present in the scutellum at the 1st day of germination: this value decreases steadily during the following days.

Documentos Relacionados

• Citrate Synthetase in Mitochondria and Glyoxysomes of Maize Scutellum
• Solubilization of Enzymes from Glyoxysomes of Maize Scutellum
• Genetic regulation of the catalase developmental program in maize scutellum: Identification of a temporal regulatory gene
• The Development of Glyoxysomes in Peanut Cotyledons and Maize Scutella 1
• Regulation of Cat1 gene expression in the scutellum of maize during early sporophytic development.