"cytosol" - 1 õppematerjal

Nimetu

18S and 5.8S rRNAs which will form the major RNA sections of the ribosome. · RNA polymerase II synthesizes precursors of mRNAs and most snRNA and microRNAs. This is the most studied type, and due to the high level of control required over transcription a range of transcription factors are required for its binding to promoters. · RNA polymerase III synthesizes tRNAs, rRNA 5S and other small RNAs found in the nucleus and cytosol. There are other RNA polymerase types in mitochondria and chloroplasts. In bacteria, the same enzyme catalyzes the synthesis of mRNA and ncRNA. RNAP is a relatively large molecule. The core enzyme has 5 subunits (~400 kDa): · 2: the two subunits assemble the enzyme and recognize regulatory factors. Each subunit has two domains: CTD (C-Terminal domain) binds the UP element of the extended promoter, and NTD (N-terminal domain) binds the rest of the polymerase.