AF477200 4050 1 795 chimeric AF477200 4050 1034 1052 T7 RNA polymerase promoter AF477200 4050 1058 1074 SP6 RNA polymerase promoter AF477200 4050 1075 1101 5' beta globin leader sequence AF477200 4050 1102 1148 multiple cloning region AF477200 4050 1155 1376 SV40 late polyadenylation signal AF477200 4050 1466 1921 phage f1 region