Dauer larva recovery in the nematode Caenorhabditis elegans—II. The effect of inhibitors of protein synthesis on recovery, growth and pharyngeal pumping

Abstract

1. 1. The requirement for protein synthesis in the recovery process of the dauer larva of Caenorhabditis elegans was investigated using several protein synthesis inhibitors. 2. 2. Cycloheximide retarded and inhibited the onset of pharyngeal pumping and the onset of SDS sensitivity in dauer larvae placed in fresh medium. It also affected longitudinal growth in recovering larvae. 3. 3. Anisomycin had similar effects to cycloheximide. Puromycin and oxytetracycline also affected longitudinal growth, but they had a milder effect on dauer larva recovery. 4. 4. Both cycloheximide and puromycin inhibited the incorporation of [ 35S]methionine into protein in recovering dauer larvae, cycloheximide being the more effective drug. 5. 5. Measurement of peptidyl transferse activity suggested that a rapid burst of protein synthesis occurs before the onset of pharyngeal pumping in recovering dauer larvae. 6. 6. Polyacrylamide gel electrophoresis revealed the retention of dauer specific protein bands when 10 mM cycloheximide was present in the recovery medium, indicating that recovery is prevented by the drug. 7. 7. Since protein synthesis, but not mRNA synthesis appears to be obligatory for dauer larva recovery, the dauer larva may represent a developmental state analogous to unfertilized oocytes or to dispausing insect embryos which contain mRNA stores which are translated when stimulated by a suitable activating trigger.