Chronic ethanol consumption results in microsome proliferation and an increase in the level of a cytochrome P-450 (P-450alc). The relative of this pathway and the alcohol dehydrogenase (ADH) pathway in ethanol metabolism in the liver is subject to debate. The ADH-negative and ADH-positive deermouse stocks have suggested that a substantial amount of ethanol metabolism may occur by non-ADH mediated pathways. The P-450alc has been purified from the deermouse and used to raise antibodies which are monospecific as judged by Western blotting. Antibodies to P-450alc inhibit ethanol metabolism in vivo. These antibodies will be used to identify cloned cDNA for P-450alc in a Lambdagtll expression lkibrary. The P-450alc cDNA will be sequenced. The mechanism of induction of P-450alc will be studied by measuring P450-alc synthesis rates in control and ethanol-fed animals using radiolabeling and specific immunoprecipitation techniques. Levels of P-450alc mRNA in control and ethanol-fed ADH-positive and ADH-negative deermice will be measured. An analysis of P-450alc mRNA levels in baboons and humans will be started. Investigation of possible genetic variation in P-450alc induction in many representative inbred mice will begin as will a survey of P-450alc gene structure in inbred mice. With P-450alc cloned DNA, the possibility exists to study variation in this gene and surrounding sequences in human alcoholic and non-alcoholic populations to identify possible genetic variation which may be of significance in controlling the expression or structure of this physiologically important protein. An analysis of DNA sequences upstream, where interesting regulatory sequences reside, from the structural gene will require the isolation of a genomic clone. This should be made readily feasible by the availability of the cDNA for P-450alc.
