USE OF ANTISENSE RNA TO HELP IDENTIFY A GENOMIC CLONE FOR THE 5 ' REGION OF MOUSE /3-GLUCURONIDASE

Abstract

It was possible to gauge the inhibition of mouse P-glucuronidase expression by injecting RNA, made from both strands of subclones of a cosmid containing the complete gene, into mouse blastomeres at the four-cell stage. Although our initial screen did not identify the 5 ' region, we were able to isolate a subclone containing homology to 20 bp coding for N-terminal amino acids of rat and human P-glucuronidase structural genes. Antisense RNA prepared from one strand of the 350 bp Pst I subclone inhibited p-glucuronidase expression by 89 % while RNA prepared from the other strand had little effect. The subclone appears to correspond to the 350 bp fragment identified by others as one including the ATG start site of mouse p-glucuronidase. 0 1989 Academic Press, Inc. Since the discovery of its natural occurrence in bacteria (l), antisense RNA has been used in attempts to study the function of eukaryotic genes both in adult tissues (2) and in embryonic systems (3-6). Antisense molecules are thought to prevent the expression of an mRNA by hybridizing either with th