Figure 10: SMART: 1. Extension and template probes anneal to template DNA forming a 3WJ; 2. DNA polymerase elongates the extension probe, thus forming a ds T7 RNA promotor region; 3. RNA polymerase binds to ds T7 promotor and produces numerous RNA transcripts which serve as signal; 4. Possible detection: a RNA binding capture probe, attached to an immobilized streptavidin; Alkaline phosphatase linked detection probe allows for substrate conversion.