What is the name of the enzyme that synthesizes RNA from a DNA template?

RNA polymerase synthesizes RNA from a DNA template.

During transcription, RNA polymerase binds a promoter and locally separates the DNA strands. It then links ribonucleotides together using one DNA strand as a template, producing RNA in the 5′-to-3′ direction. Unlike DNA polymerase, it generally does not require a pre-existing primer.

Bacteria typically use one main RNA polymerase, while eukaryotic cells use several nuclear forms. RNA polymerase I mainly makes ribosomal RNA, RNA polymerase II makes messenger RNA and some other RNAs, and RNA polymerase III makes transfer RNA and selected small RNAs.

Transcription is the first major step in gene expression. The resulting RNA may be processed, translated into protein, or function directly as a structural, regulatory, or catalytic molecule.