Question

Describe how the carboxy terminal domain (CTD) of RNA polymerase II is involved in initiation and elongation of transcription. HTML Editori B I VA - A - Ix E 1 1 1 x X, DE T TH 12pt Paragraph Tube O words

Answer 1

U is the largest Subunil- The in mainly c- terminal domain (CTO) of the RNA polymerase CTỨ plays various important roles transcription in initiation , elongation and termination Eukaryotes have DNA dependent- polymerasek (RNAPs). : RNAP I , RAPI , is responsible for the synthesis of all many noncoding RNAA (nic RNAs), consist of 3 Polypeptides Among which Robi porsented the largest enzyme't catalyst activity three nuclear RNA and RNAP RNAP I mRNA and It also contain CTD RNAPI Pre-mRNA етр The CTD is consial up to 52 repeats of the Sequence. - Tyr - Ser - Pro- Thu Ser - Pro-sera Initiation in initiation of transcription, the phot phorylation an important regulation mechanism. of the CTD..

Thit allowa attraction and rejection of factor a function in the transcription. that- have The CTD can be considered a platform for tranAcription facitors. the CTD it Ber5 residues. to create Elong ation From pre initiation to elongation, the cto phosphorylated CTD phosphorylation state capping enzyme binding. Elongation - related factors such as the Second ܦ܀ s'end processing factors of. and Set 2 bind to the CTD in the third stage uper Seiz of the ile is of phoxphorylation Because of this bindi binding CTD kinase - 1 ser 5p repeatá to generate 1.5P repeat in vitro Finally near the 3 end of gene widely believed that co phosphorylation it dominated it consistent with the binding specificity and localization of Some 3'-end processing factors i So, the main function of CTD is to serve flexible Scaffold for binding variety nuclear fac tort. Serap this by طه a