Translational arrest in hypoxic potato tubers is correlated with the aberrant association of elongation factor EF-1 alpha with polysomes.
Translation elongation factor EF-1 alpha became stably associated with potato tuber polysomes at the onset of hypoxia, coincident with a sharp rise in lactate and decrease in tissue pH. This aberrant association of EF-1 alpha with polysomes also occurred when aerobic tuber extracts were acidified in vitro. Upon resumption of protein synthesis, an increase in the steady-state levels of EF-1 alpha, and expression of an EF-1 alpha/GUS transgene was observed. These results indicate that translational arrest results from to the failure of EF-1 alpha to dissociate from ribosomes during the elongation cycle, and that restoration of protein synthesis is coordinated with expression of EF-1 alpha.
Vayda
M E
ME
Department of Biochemistry, Microbiology and Molecular Biology, University of Maine, Orono 04469-5735, USA.
Shewmaker
C K
CK
Morelli
J K
JK
D000255:Adenosine Triphosphate / Q000032:analysis; D018506:Gene Expression Regulation, Plant; D006863:Hydrogen-Ion Concentration; D007773:Lactates / Q000032:analysis; D018551:Solanum lycopersicum / Q000235:genetics; D010100:Oxygen / Q000494:pharmacology*; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism; D030821:Plants, Genetically Modified; D011132:Polyribosomes / Q000378:metabolism*; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D014176:Protein Biosynthesis; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D011198:Solanum tuberosum / Q000187:drug effects / Q000378:metabolism*; D013997:Time Factors
D007773:Lactates; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors; D010940:Plant Proteins; D011993:Recombinant Fusion Proteins; D000255:Adenosine Triphosphate; D010100:Oxygen