derives from/develops from Rat-1 cell Rat1-R12 cell BTO:0003294 BrendaTissueOBO The Rat1-R12 cell line was derived from the Rat-1 cell line. Rat-1 cells were stably transfected with the pUHD15-1 neo plasmid which contains the tetracycline transactivator (tTA) gene and the neomycin resistance gene.