Diapause in the mosquito Culex pipiens evokes a metabolic switch from blood feeding to sugar gluttony.
A key characteristic of overwintering dormancy (diapause) in the mosquito Culex pipiens is the switch in females from blood feeding to sugar gluttony. We present evidence demonstrating that genes encoding enzymes needed to digest a blood meal (trypsin and a chymotrypsin-like protease) are down-regulated in diapause-destined females, and that concurrently, a gene associated with the accumulation of lipid reserves (fatty acid synthase) is highly up-regulated. As the females then enter diapause, fatty acid synthase is only sporadically expressed, and expression of trypsin and chymotrypsin-like remains undetectable. Late in diapause (2-3 months at 18 degrees C), the genes encoding the digestive enzymes begin to be expressed as the female prepares to take a blood meal upon the termination of diapause. Our results thus underscore a molecular switch that either capacitates the mosquito for blood feeding (nondiapause) or channels the adult mosquito exclusively toward sugar feeding and lipid sequestration (diapause).
Robich
Rebecca M
RM
Department of Entomology, Ohio State University, 318 West 12th Avenue, Columbus, OH 43210, USA.
Denlinger
David L
DL
D000595:Amino Acid Sequence; D000818:Animals; D001769:Blood / Q000378:metabolism; D050260:Carbohydrate Metabolism; D053818:Chymases; D003465:Culex / Q000378:metabolism* / Q000502:physiology; D004032:Diet; D064429:Fatty Acid Synthases / Q000235:genetics; D005247:Feeding Behavior; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D006605:Hibernation / Q000502:physiology*; D008660:Metabolism / Q000502:physiology; D008969:Molecular Sequence Data; D012621:Seasons; D016415:Sequence Alignment; D012697:Serine Endopeptidases / Q000235:genetics; D014357:Trypsin / Q000235:genetics
D064429:Fatty Acid Synthases; D012697:Serine Endopeptidases; D053818:Chymases; D014357:Trypsin