BIOL-L211 Lecture 30 Outline of Last Lecture I. Genetic CodeII. Cracking the Genetic CodeIII. Degeneracy of the Genetic CodeOutline of Current Lecture I. ArticleII. TranslationIII. Ribosome CompositionCurrent LectureIntroduction to TranslationI. ArticleA. "Google Wants to Store Your Genome" –MIT Technology ReviewB. Google cloud allows storage and sharing of genomic data (~100GB per genome)1. $25/year to store DNA information2. Can additionally pay to access other genomesC. Goal:1. Create a large, functional genomic database2. Provide a resource that can be accessed by medical doctors to allow for quick comparison of genomic information (between patients with similar conditions)D. Additional competition between Google, IBM, and MicrosofII. TranslationA. Translation is the process of protein production following transcriptionThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.B. Ribosomes: organelles responsible for translation1. Composed of a large and small subunit2. The small subunit recruits and binds mRNA3. Initiator tRNA contacts the start codon4. Large subunit binds5. Translation begins following the template 5' to 3'C. Translation in Prokaryotes:1. Due to lack of a nucleus, transcription and translation are not isolated processes; there is no spatial separation2. Transcription and translation can thus occur simultaneously3. Polycistronic mRNA: mRNA that has multiple ORFsa. Will occur if genes are organized in an operonb. Note: Each ORF encodes a proteinc. Each ORF has a start and stop codonD. Translation in Eukaryotes1. Transcription takes place in the nucleus2. Translation occurs in the cytoplasm3. Monocistronic mRNA: mRNA that has only one ORF E. Aminoacyl-tRNA Synthetases1. Uncharged tRNA: tRNA with no amino acid attached2. Charged tRNA: tRNA with its amino acid on the acceptor stem3. Each tRNA is charged by a specific aminoacyl-tRNA synthetaseIII. Ribosome CompositionA. Ribosomal RNA (rRNA) and ProteinsB. Large Subunit1. Holds peptidyl transferase centera. This center is responsible for forming the bonds between amino acids to form proteins2. 60S in eukaryotes; 50S in prokaryotesa. Where S = "Svedberg unit" = measure of centrifugation velocityC. Small Subunit1. First to bind to mRNA2. Location where tRNAs read mRNA codons3. 40S in eukaryotes; 30S in prokaryotesD. Eukaryotes have 80S ribosomes; Prokaryotes have 70S ribosomes*Note: Antibiotics ofen target the ribosomes of bacteriaE. A, P, and E sites1. P site: recruits initiator tRNAa. "P" site is "p"roactive2. Initiator tRNA interacts with AUG (start codon) and then the large subunit comes3. A site: sets alignment of the second codona. The second tRNA interacts with mRNA hereb. Peptide bond is formed and the ribosome moves over to the next codon- initiator tRNA transferred to E site4. E site: tRNA is "e"jected*Note: during this process, the tRNA bridges the gap between the large and small ribosomal
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