Causal connection between detoxification enzyme activity and consumption of a toxic plant compound.

摘要: Insect herbivores can increase their detoxification activities against a particular plant poison in response to prolonged ingestion of the same compound. For example, larval tobacco hornworms (Manduca sexta) experience dramatic cytochrome P450 activity nicotine after ingesting nicotine. While it is generally assumed that this induction process permits increased consumption toxic tissues, we are not aware any direct experimental support for assumption. Using two-tiered approach, examined functional significance M. sexta larvae but non-deterrent concentration First, related time-course midgut microsomes changes consumption. When offered diet, failed show significant before 36 h, which was coincident with aldrin and Second, determined whether inhibiting induced affected We found following metabolism could be strongly inhibited by treatment piperonyl butoxide, itself did inhibit These results provide evidence causal connection between P450-mediated