BIOL 2321 Lecture Notes - Lecture 28: Purine, Cistron, Ribosomal Rna
10 Jan 2016
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Document Summary
Each trna identifies the appropriate codon on the mrna and adds this amino acid to the growing protein chain. This results in a dna-mrna-ribosome complex, as shown. As the mrna grows, the number of ribosomes associated with it increases. Growing polypeptide chains on the ribosome are not visible due to their small size: ctd in process of capping and poly(a) tail addition: during. Rna pol ii-mediated transcription of mrna, the repetitive c- terminal domain (ctd) unique to the pol ii largest subunit acts as a "processing platform"that enhances both capping and polyadenylation. A polyribosome (or polysome) is a complex of a mrna molecule and two or more ribosomes that is formed during active translation: recognition of mrna and identification of the initiation codon: eukaryotes: 5"-cap on mrna recognized, then ribosome scans mrna for first aug after cap.
