Yeast DNA-dependent RNA polymerase (null)

Yeast DNA-dependent RNA polymerase refers to a family of large, multi-subunit enzymes in yeast (Saccharomyces cerevisiae) responsible for transcribing DNA into RNA. There are three primary nuclear forms: - RNA polymerase I (Pol I): synthesizes large ribosomal RNA precursors (e.g., 35S rRNA in yeast) necessary for ribosome assembly. - RNA polymerase II (Pol II): synthesizes messenger RNAs (mRNAs), most small nuclear RNAs (snRNAs), and microRNAs, essential for gene expression. - RNA polymerase III (Pol III): synthesizes transfer RNAs (tRNAs), 5S rRNA, and various other small RNAs. These enzymes share a core mechanism and structural homology, typically utilizing magnesium ions for catalysis and containing multiple subunits that coordinate transcriptional initiation, elongation, and termination[1][3][6]. Yeast RNA polymerases are essential for all aspects of gene expression and cellular function. Their malfunction or deletion leads to loss of viability[1][6]. While they are not commonly targeted by clinical therapeutics, they are an important focus in biotechnology and genetics, especially in studies of eukaryotic gene regulation.

Other names

Yeast RNA polymeraseSaccharomyces cerevisiae RNA polymeraseYeast DNA-directed RNA polymerasePol IPol IIPol III

Nucleotidyl transferase activity: catalyzes the polymerization of ribonucleotides using a DNA template, guided by two-metal ion catalysis (magnesium ions at the catalytic site) which facilitates nucleophilic attack by the 3'-OH group of the growing RNA chain on the α-phosphate of an incoming ribonucleotide triphosphate, releasing pyrophosphate[1][3].