Document Type

Thesis - University Access Only

Award Date


Degree Name

Master of Science (MS)

Department / School

Biology and Microbiology

First Advisor

Raymond R.R. Rowland


The agouti gene directs cyclic deposition of black eumelanin and yellow pheomelanin pigments in the coats of wild-type (agouti) mice. Specific mutations in the agouti gene restrict pigment synthesis to pheomelanin or to eumelanin, exclusively. Pheomelanogenic mutants exhibit dramatic physiological abnormalities including obesity, diabetes, infertility, immunological depression, and increased susceptibility to cancer. These multiple effects are thought to result from dysregulated gene expression. Molecular approaches provide the most fundamental correlation between gene expression and phenotype. The overall goal of this research is to understand, at the molecular level, how agouti expression causes phenotypic differences. The purpose of this thesis was to define agouti expression within the context of melanogenesis in vivo and to establish an in vitro model for the study of its action. Northern analysis showed that regenerating wild-type and yellow hair follicles express agouti during pheomelanogenesis, but black follicles do not express agouti. In situ hybridization demonstrated the specific locations of agouti expression within yellow and wild-type skin, and the ectopic pattern of expression in yellow. An in vitro model was designed to mimic ectopic expression within a cellular system. This model can be used to study the cellular effects of ectopic agouti expression as it occur in the lethal yellow mouse.

Library of Congress Subject Headings

Mice -- Molecular genetics
Gene expression
Melanins -- Synthesis




South Dakota State University



Rights Statement

In Copyright