P-element transformation constructs. (a) The USC1.0 vector for the tet-on system. Unique PstI and EcoRI sites are located downstream of the tet-on promoter, enabling cloning of cDNAs. cDNAs should contain their own ATG start codons and polyadenylation signal sequences. (b) The PGMsense construct for conditional overexpression of PgmS. (c) The PGMinvrpt construct, containing an approximately 1 kb inverted repeat of PgmM coding region, as indicated by inverted arrows.