The fresh new “RNA factory” concept to possess eucaryotic RNA polymerase II. Not simply really does the fresh new polymerase transcribe DNA into the RNA, but it also carries pre-mRNA-handling healthy protein into their end, which can be then transferred to the new nascent RNA in the suitable (a lot more. )
When RNA polymerase II has produced in the 25 nucleotides from RNA, the 5? stop of your own brand new RNA molecule is actually modified by the inclusion of good “cap” that include a changed guanine nucleotide (find Figure six-22B). The latest capping impulse is accomplished by the three nutrients acting in series: you to (an effective phosphatase) removes you to phosphate about 5? prevent of one’s nascent RNA, some other (an excellent guanyl transferase) contributes an excellent GMP during the a contrary linkage (5? to help you 5? as opposed to 5? to 3?), and you will a third (a beneficial methyl transferase) contributes an effective methyl classification for the guanosine (Contour six-24).