Figure 2

The constructs used for injection into the macronuclear anlagen. (a) Vector pCE5 contains two macronuclear precursor sequences homologous to a 1.1 and a 1.3 kb macronuclear DNA molecule. The 1.1 kb homologous precursor sequence contains 2 IES, and the 1.3 kb homologous sequence contains 3 IES. The two precursor sequences are separated by an 11 bp spacer and are flanked by micronuclear-specific sequences on both sides [26]. A 500 bp polylinker was inserted to modify the 1.3 kb homologous macronuclear precursor sequences [25]. (b) pCE12-20: deletion constructs derived from pCE5. Primers used for construction of the deletion vectors and for PCR analysis are shown above and below the maps. The sequences of the primers are listed in Table 1.