BIO206H5 Lecture Notes - Lecture 15: Aminoacyl Trna Synthetase, 16S Ribosomal Rna, Aminoacyl-Trna

• School: UTM
• Department: Biology
• Course: BIO206H5
• Professor: George S Espie

Document Summary

Functional sites: a, p, e, ef-tu, ef-g, mrna. Must be assembled on a continuous ongoing process; to satisfy demands of eukaryotic cell, multiple copies of the genes that code for the ribosomal rna are required and they must be transcribed continuously. Eukaryotic cells may contain millions of ribosomes. (max ~100 000 for prokaryote) The dna sequence encoding rrna are called rdna & are located on multiple chromosomes. Rdna is found in nucleolar organizational regions of the genome of eukaryotic cells. In nondividing cells, rdna genes are clustered in the nucleoli, where ribosomes are produced. A single gene encodes an hnrna = 43s. The 43s transcript contains the 5. 8s, 18s & 28s sequences. Multiple copies of the rrna genes are arranged in tandem. A non-transcribed spacer separates transcription units in a ribosomal gene cluster. rrna. 43s precursor (primary rna that contains segments of 18s, 5. 8s and 28s segments) 5" & 3" ends removed/cleaved; formation of the 41s pre-rrna.