Phosphorylation of an envelope-associated Hsp70 homolog in amyloplasts isolated from cultured cells of sycamore (Acer pseudoplatanus L.).
The presence of Hsp70 and Hsp60 molecular chaperones in amyloplasts isolated from cultured sycamore cells was analyzed by immunoblotting. Hsp70 homologs were located in both amyloplast envelope and stromal fractions, but no Hsp60 homologs were detected in any of the different suborganellar fractions. Incubation of whole amyloplasts or their envelope fraction with Mg2+ gamma-32P-ATP resulted in a rapid phosphorylation of the envelope-associated Hsp70 homolog, which constitutes a major target of phosphorylation in these plastids.
Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Argentina.
S K
SK
Checa
A M
AM
Viale
D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D018834:Chaperonin 60 / Q000276:immunology / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D015151:Immunoblotting; D015388:Organelles / Q000378:metabolism; D010766:Phosphorylation; D010940:Plant Proteins / Q000276:immunology / Q000378:metabolism*; D018087:Plastids / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D014197:Trees / Q000737:chemistry* / Q000166:cytology
D018834:Chaperonin 60; D018840:HSP70 Heat-Shock Proteins; D010940:Plant Proteins