title: Circadian rhythm of trehalose in the face fly Musca autumnalis de Geer.
abstract: Trehalose levels were determined over two 24 hr spans in groups of face fly adults 3-4 days after emergence from the puparium. Face fly pupae were placed in rearing chambers at 27 degrees C in a staggered light-dark regimen, LD 16:8, so that at a given clock hour, samples could be obtained at several different hours after lights on (HALO). Trehalose was determined in hemolymph collected from a puncture in the intersegmental membrane of the abdomen. Treated hemolymph samples were passed through a Bio-Rad Amino 5-S disaccharide column and a Waters 410 refractive index detector was used to differentiate among sugars. The circadian acrophase derived by cosinor analysis in hemolymph trehalose (when the values were 25.49 and 26.86 micrograms/microliters on the first and second days respectively) occurred at -226 degrees (ca 15 HALO) and the bathyphase at 24 HALO. The mesor = 11.82 micrograms/microliters trehalose, the amplitude = 8.57 micrograms/microliters trehalose and the P-value for presence of a rhythm was 0.003. Based on these data, differences between control and test flies in a bioassay of hypertrehalosemic activity would be most easily observed at 0-8 HALO, while exogenous hypotrehalosemic activity would be best assayed at 12-20 HALO.
authors.affiliation: Beltsville Agricultural Research Center, U.S. Department of Agriculture, MD 20705.
authors.forename: D K
authors.initials: DK
authors.lastname: Hayes
authors.forename: T G
authors.initials: TG
authors.lastname: Bird
authors.forename: G D
authors.initials: GD
authors.lastname: Mills
authors.forename: H
authors.initials: H
authors.lastname: Frankoff
mesh_terms: D000818:Animals; D002940:Circadian Rhythm / Q000502:physiology*; D003624:Darkness; D006458:Hemolymph / Q000378:metabolism; D008027:Light; D009117:Muscidae / Q000378:metabolism*; D014199:Trehalose / Q000378:metabolism*
chemical_list: D014199:Trehalose