Regulation of proteinase levels in the nematode Caenorhabditis elegans. Preferential depression by acute or chronic starvation.
Acute starvation of the wild-type of the nematode Caenorhabditis elegans depresses the level of cathepsin D by 65% within 4-8 h and the level of the thiol cathepsins Ce1 and Ce2 to about the same extent after 24 h. There is no parallel loss of lysosomal beta-glucosidase or beta-hexosaminidase activities. In strains which are chronically starved as a result of mutations which compromise feeding behaviour (unc-52) or nutrient uptake into the intestinal cells (daf-4), cathepsin D levels are decreased to about 15% of the level in fully fed wild-type animals. We suggest that the decline in the cathepsin D level results from autodigestion when alternative protein substrates are depleted in the lysosomes.
Hawdon
J M
JM
Department of Biological Sciences, University of Pittsburgh, PA 15260.
Emmons
S W
SW
Jacobson
L A
LA
D000818:Animals; D001329:Autolysis; D002107:Caenorhabditis / Q000201:enzymology*; D002403:Cathepsins / Q000378:metabolism*; D008247:Lysosomes / Q000201:enzymology; D011506:Proteins / Q000378:metabolism; D013217:Starvation; D001617:beta-Glucosidase / Q000378:metabolism
D011506:Proteins; D001617:beta-Glucosidase; D002403:Cathepsins