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.
Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden.
Emma
E
Svensk
Marcus
M
Ståhlman
Carl-Henrik
CH
Andersson
Maja
M
Johansson
Jan
J
Borén
Marc
M
Pilon
D000222:Adaptation, Physiological / Q000235:genetics*; D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics / Q000502:physiology; D029742:Caenorhabditis elegans Proteins / Q000235:genetics*; D003080:Cold Temperature; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism; D050356:Lipid Metabolism / Q000235:genetics*; D008565:Membrane Proteins / Q000235:genetics*; D009154:Mutation; D010713:Phosphatidylcholines / Q000378:metabolism; D054419:Receptors, Adiponectin / Q000235:genetics* / Q000378:metabolism; D013696:Temperature
D029742:Caenorhabditis elegans Proteins; D005227:Fatty Acids; D007328:Insulin; D008565:Membrane Proteins; C587163:PAQR-2 protein, C elegans; D010713:Phosphatidylcholines; D054419:Receptors, Adiponectin