title: Differential hepatic gene expression of a dietary specialist (Neotoma stephensi) and generalist (Neotoma albigula) in response to juniper (Juniperus monosperma) ingestion.
abstract: Dietary specialization is thought to be rare in mammalian herbivores because of limitations of their detoxification system in processing large doses of a single type of plant secondary compound (PSC). Therefore, in order to specialize on a single species of plant, mammalian herbivores must have a highly efficient detoxification system for the particular types of PSCs they ingest. Using microarray technology, we looked at the expression of hepatic genes of a dietary specialist, Neotoma stephensi, and a sympatric generalist, Neotoma albigula, in response to diets containing different levels of one-seeded juniper (Juniperus monosperma). We found large between species differences in gene expression, as well as large within species differences when specialists fed a low juniper diet (25% juniper) were compared to specialists fed their ecologically relevant level of juniper (70% juniper). We also tested the hypothesis that the specialist relies on less costly phase I detoxification enzymes more than phase II compared to the generalist. Although we found that the specialist had higher cumulative as well as average expression of phase I versus phase II enzymes, the generalist had a similar pattern of expression for phase I versus phase II enzymes.
authors.affiliation: Department of Zoology, Weber State University, Ogden, USA.
authors.forename: Michele M
authors.initials: MM
authors.lastname: Skopec
authors.forename: Shannon
authors.initials: S
authors.lastname: Haley
authors.forename: M Denise
authors.initials: MD
authors.lastname: Dearing