A model scheme of isothermal RNA amplification with NV3Dpol. (i) NV3Dpol interacts to the CCC sequence at the 3’-terminus of RNA template (RNA(+)), and (ii) made dsRNA (RNA(+) - RNA(-)). Sometimes the enzyme adds cytidine(s) at the 3’-terminus of RNA(-) by TNT activity. (iii) NV3Dpol interacts to the breathing CCC sequence. (iv) NV3Dpol replicates the dsRNA with displacing the RNA strand. The displaced RNA strand is recycled as a RNA template.