IDENTIFICATION OF ANDROGEN-REGULATED GENES IN MOUSE KIDNEY BY REPRESENTATIONAL DIFFERENCE ANALYSIS AND RANDOM ARBITRARILY PRIMED POLYMERASECHAIN-REACTION

The molecular nature of tissue-specific gene regulation by androgens h as not been well defined. partly as a result of the variable expressio n and incomplete regulation of currently available gene models. We hav e therefore aimed to establish more informative models by identifying alternative genes whose expression is tightly and coordinately regulat ed by androgens. Female C57BL/6 mice were dosed with dihydrotestostero ne- or sham-treated for 8 days, after which kidneys were removed and c omplementary DNA (cDNA) prepared. We then applied the subtractive hybr idization techniques of random arbitrarily primed-PCR and PCR-coupled subtractive hybridization method of cDNA representational difference a nalysis to the isolated cDNA. In addition to well characterized androg en-regulated genes [e.g. KAP (kidney androgen-regulated protein)], we demonstrate the differential expression of sir: genes previously not k nown to be under androgen control. RNA levels of SA, Cytochrome P450 4 B1, IL-GST (interleukin-6 signal transducer). OATP (organic anion tran sporter), and a newly identified gene, MJAM, were up-regulated by andr ogen, while 16-alpha-hydroxylase was decreased. Expression of these tr anscripts was inhibited in dihydrotestosterone-treated females by flut amide and in males by castration, confirming their dependence on andro gens. Although all the genes demonstrate tissue-specific regulation by androgen. SA show-ed both kidney specificity and absolute requirement for androgen for its expression. These newly identified androgen-regu lated genes will constitute very useful models for studying the nature of tissue-specific gene regulation by androgens.