Biology 3593B Study Guide - Quiz Guide: Ribosome-Binding Site, The Hairpin, Reading Frame
Document Summary
Promoter = region of dna that initiates transcription of a particular gene. Multi-protein transcription complex binds to and occupies the promoter dna sequence. Transcription machinery accumulates complementary rna known as messenger rna mrna (uracil instead of thymine) It keeps transcribing dna to rna, first past the ribosomal binding site (rbs) then past the open reading frame (orf), eventually transcribing the transcription terminator (tt) Once transcribed the sequence and environment of the mrna tt sequence favour hairpin formation. The hairpin serves to "eject" the transcription machinery from the dna strand thereby terminating transcription. It is made of wc paired bases on the straight part and unpaired bases on the end. Orf encodes amino acid sequence in a single reading frame. Ribosome will proceed along the mrna in 5" to 3" direction translating rna into polypeptide. Ribosomes tend to dissociate at stop codon, terminating translation. Orfs as tools for whole cell biocatalyst design.
