Method for producing a sense RNA molecule

A method for producing a sense RNA molecule, comprising:

• a) providing a single stranded cDNA molecule having 5′ and 3′ ends;
• b) attaching a homopolymeric tail for annealing a single stranded promoter template to the 3′ end of said single stranded cDNA molecule using terminal deoxynucleotidyl transferase;
• c) annealing a single stranded promoter template consisting essentially of a single RNA polymerase promoter sequence at a 5′ end and a sequence complementary to the homopolymeric tail at a 3′ end thereof to said homopolymeric tail through base pairing with the complementary sequence of the single stranded promoter template, wherein said single stranded promoter template is not extendable with DNA polymerase;
• d) extending said homopolymeric tail such that said single stranded promoter template is converted to a double stranded promoter;
• and
• e) initiating RNA transcription using an RNA polymerase which recognizes said double stranded promoter,
• thereby producing a sense RNA (sRNA) molecule.