PAQR-2 Regulates Fatty Acid Desaturation during Cold Adaptation in C. elegans

C. elegans paqr-2 is homologous to the insulin-sensitizing adiponectin receptors in mammals,and essential for adaptation to growth at 15°c,a low but usually acceptable temperature for this organism. by screening for novel paqr-2 suppressors,we identified mutations in genes involved in phosphatidylcholine synthesis (cept-1,pcyt-1 and sams-1) and fatty acid metabolism (ech-7,hacd-1,mdt-15,nhr-49 and sbp-1). we then show genetic evidence that paqr-2,phosphatidylcholines,sbp-1 and δ9-desaturases form a cold adaptation pathway that regulates the increase in unsaturated fatty acids necessary to retain membrane fluidity at low temperatures. this model is supported by the observations that the paqr-2 suppressors normalize the levels of saturated fatty acids,and that low concentrations of detergents that increase membrane fluidity can rescue the paqr-2 mutant. © 2013 svensk et al.