Source:http://linkedlifedata.com/resource/umls/id/C0035685
MSH: An enzyme that catalyses RNA-template-directed extension of the 3'- end of an RNA strand by one nucleotide at a time, and can initiate a chain de novo. (Enzyme Nomenclature, 1992, p293),NCI: An enzyme that catalyzes the template-directed addition of ribonucleotides to the 3' end of a growing RNA chain. The enzyme utilizes single-stranded RNA as a template.