Practice question

Primase activity is fundamentally RNA polymerizing, incorporating ribonucleoside triphosphates ATP, UTP, GTP, CTP complementary to DNA template without requirement for existing primer, unlike DNA polymerase. In bacteria, DnaG is monomeric RNA polymerase interacting with helicase DnaB, synthesizing ~10 nt primers for Okazaki fragments. In eukaryotes, heterotetrameric Pol α-primase combines two primase subunits Pri1/Pri2 for RNA synthesis with Pol α DNA polymerase extension of about 20 nucleotides. Despite functional similarity to RNA polymerase II that transcribes mRNA, primase is distinct gene family but mechanistically classified as RNA polymerase due to ribonucleotide use.