N-acetylation pharmacogenetics: a gene deletion causes absence of arylamine N-acetyltransferase in liver of slow acetylator rabbits.
The New Zealand White rabbit provides a widely used animal model for the human acetylation polymorphism, which confers marked interindividual variation in the effect and toxicity of numerous drugs, chemicals, and potential carcinogens. The relationship of a recently isolated cDNA clone, designated rnat, to genetically polymorphic arylamine N-acetyltransferase (NAT; acetyl-CoA:arylamine N-acetyltransferase, EC 2.3.1.5) of rabbit liver was established by its expression in monkey kidney COS-1 cells: (i) cytosols from transfected cultures contained high levels of an Ac-CoA-dependent NAT activity, which was kinetically indistinguishable from that observed in cytosols from livers of genetically rapid-acetylator rabbits; (ii) transfected cells also contained an immunoreactive protein, recognized by NAT-specific antibodies, with identical electrophoretic mobility to NAT from rabbit liver. The rnat clone and anti-NAT antibodies were then used to study the relationship between NAT activity, liver enzyme protein, and the level of mRNA in livers from in vivo phenotyped rapid- and slow-acetylator rabbits. Livers from slow acetylators were devoid of both immunodetectable NAT protein and its corresponding mRNA. Analysis of genomic DNA with a panel of restriction enzymes revealed the loss of specific hybridizing bands in the DNA of slow-acetylator rabbits. These data strongly suggest that defective arylamine N-acetylation in the rabbit model is caused by a gene deletion resulting in an absence of specific mRNA and NAT enzyme protein.
Blum
M
M
Department of Pharmacology, University of Basel, Switzerland.
Grant
D M
DM
Demierre
A
A
Meyer
U A
UA
D000107:Acetylation; D000123:Acetyltransferases / Q000235:genetics*; D000818:Animals; D001191:Arylamine N-Acetyltransferase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D015139:Blotting, Southern; D015153:Blotting, Western; D002460:Cell Line; D002872:Chromosome Deletion; D004247:DNA / Q000235:genetics; D015870:Gene Expression; D005796:Genes; D008099:Liver / Q000201:enzymology*; D010641:Phenotype; D011817:Rabbits; D015183:Restriction Mapping; D014162:Transfection
D004247:DNA; D000123:Acetyltransferases; D001191:Arylamine N-Acetyltransferase