BIOL 1105 Study Guide - Midterm Guide: Ubiquitin Ligase, Lac Repressor, Alternative Splicing
Document Summary
After transcription, translation is immediate in prokaryotes. Spliceosomes remove the introns from pre rna transcript. Alternative splicing benefit is that you can make multiple genes from it by shuffling and splicing different genes. Mirna and sirna- both double stranded rna and target specific mrna, their sequence is opposite to mrna sequences, chops mrna up so they don"t go to translation(shutting genes down)(euk) Protein degradation takes place post-translational; ubiquitin is necessary tagged on to protein to be recognized by proteasome to be digested, protein is then digested and ubiquitin is recycled and attached to ubiquitin ligase and reused(euk) Advantage of operons- react to environmental changes, can be multiple genes per operon, operon has promoter region, dna is then transcribed. When lactose is present, allolactose inhibits the lac repressor and therefor the repressor can not bind to the operon and transcription occurs.
