FAQ: How can I improve on a low yield of RNA from the transcription reaction?

If the transcription reaction with your template generates full-length RNA but the yield is significantly lower than expected, it is possible that contaminants in the DNA template are inhibiting the RNA polymerase, or the DNA concentration may be incorrect. Alternatively, additional purification of DNA template may be required. 

Adding 5mM DTT (final) to the transcription reaction may also help improve RNA yield.