Maize plastids

In order to begin studying development and ultimately, in this case, the interactions between the organelle and the nuclear-cytoplasmic systems in maize plastid membrane development, it is necessary to establish the base line to know what is present before the structure or organism has developed, what is added, and finally how and why new elements are set into place. We had only a little information on what is in the etioplast membrane that may be related to the photosynthetic function of the mature chloroplast. 

Table III. Effect of a Dark Period after 5 h of Illumination on the Development of Acid-to-Base Phosphorylation Capacity by Green Maize Plastids ...

Table IV. Molecular Weights of the Most Prominent Polypeptides in Prolamellar Bodies and Thylakoids of Maize Plastids... 

Nieto-Sotelo, J. Ho, T.-H.D. (1987). Absence of heat shock protein synthesis in isolated mitochondria and plastids from maize. Journal of Biological Chemistry, 262, 12288-92. 

In green algae and in leaf cells of higher plants, ADP-Glc PPase has been demonstrated to reside in the chloroplast (82). More recently, using plastids isolated from maize and barley endosperm (83-85), the existence of two ADP-Glc PPases, a plastidial form, and a major cytosolic form were found. Subsequently, cytosolic forms of ADP-glucose pyrophosphorylase have been found in wheat (86, 87) and rice (88). Because starch synthesis occurs in plastids, it was proposed that in cereal endosperms, synthesis of ADP-Glc in the cytosol requires the involvement of an ADP-Glc carrier in the amyloplast envelope (85). Subsequently, characterization of the ADP-Glc transporter has been reported for maize endosperm (89, 90), barley endosperm (91), and wheat endosperm (92). 

Cytoplasmic and plastidic ACCs from wheat are 2260 amino acids and 2311 long, respectively, and their sequences are 67% identical [12]. A chloroplast targeting signal is present at the N-terminus of the multidomain plastid ACC from wheat [13], maize [14], and Brassica napus [15]. 

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