ABSTRACT
A partial fragment of novel sequence (arr, adriamycin-resistant related) was previously identified using the differential display (DD)-PCR technique with adriamycin-resistant L1210 variant (L1210AdR), which shows a typical multidrug resistant (MDR) phenotypes. The present research shows the isolation of full length arr cDNA sequence. To clone the full length cDNA of arr gene, DD-PCR fragments were subjected to 5'- and 3'-Rapid Amplification of cDNA End (RACE) method. The cloned arr cDNA consisted of 770 bases and contained an open reading frame of 153 bases, encoding a protein of 51 amino acid with the molecular mass of 4 kDa by in vitro translation reactions. Northern blot analysis showed that a 770 bases transcript arr gene was overexpressed in adriamycin-resistant L1210 variant, but not in the parent suggesting that the arr gene may be involved in the adriamycin-resistant phenotypes.