Age and starvation effects on hypertrehalosemic hormone-dependent gene expression of cytochrome P4504C1 in the cockroach, Blaberus discoidalis
1996
Lu, K.H. | Bradfield, J.Y. | Keeley, L.L.
Expression of the gene for cytochrome P4504C1 (= CYP4C1) is stimulated by the hypertrehalosemic hormone (= Bld-HrTH) in the fat body of the cockroach Blaberus discoidalis. The natural pattern for CYP4C1 expression was determined for the fat body of adult male B. discoidalis, and effects by the absence of food and water were assessed. CYP4C1-mRNA levels did not change significantly in the fat body of fed insects during the first 10 days of adult life; however, absence of food and water increased the CYP4C1 expression by 2.5 to 5 times that of fed animals. Decapitation prevented the starvation-related increase in gene expression indicating that the starvation effect was mediated by the head. Starvation-induced CYP4C1 expression was suppressed to the level of normally fed insects following re-exposure to food and water. Insects from which the corpora cardiaca (the endocrine source of Bld-HrTH) were extirpated did not exhibit the starvation-related increase in CYP4C1 expression. The increase in CYP4C1 expression during restriction from food and water was related to the absence of food since insects provided water without food still showed increased CYP4C1 expression. These results suggest that restriction from food consumption stimulates the secretion of Bld-HrTH which results in increased CYP4C1 expression. It is speculated that cytochrome P4504C1 participates in fatty acid metabolism that is regulated by Bld-HrTH as an adaptation to starvation.
显示更多 [+] 显示较少 [-]