Isolation and Characterization of Mutations in the Mouse APRT Gene that Encode Functional Enzymes with Resistance to Toxic Adenine Analogs

Adenine phosphoribosyltransferase (APRT, EC 2.4.2.7) is a purine salvage enzyme that catalyses the reaction between adenine and 5-phosphoribosylpyrophosphate (PRPP) to form AMP. Expression of the aprt gene is not required for cell survival in culture, therefore, it may be selected against by growing cells in the presence of toxic adenine analogs such as 2,6-diaminopurine (DAP). In general, DAP-resistant cell lines do not exhibit significant levels of APRT activity (Taylor and Sahota, 1989).