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Molecular Genetics. Protein. DNA. Phenotype. RNA. Genome Gene. The flow of information:. 1. Storage. 2. Replication. 3. Gene Expression. Transcription. Translation. Flow of Genetic Information. Flow of Genetic Information. Translation. Cap. Start of genetic message.
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Molecular Genetics Protein DNA Phenotype RNA Genome Gene The flow of information: 1. Storage 2. Replication 3. Gene Expression Transcription Translation
Translation Cap Start of genetic message • Translation requires: • Messenger RNA (mRNA) • Transfer RNA (tRNA) • Ribosomes • ATP • Enzymes (translation factors) End Tail
Translation • Transfer RNA (tRNA): • Molecular interpreter • Matches amino acids with codons in mRNA using anticodons Amino acid attachment site Anticodon
Translation tRNA Structure
Translation • Ribosomes: • Coordinate the functions of mRNA and tRNA • Made of two subunits • Contain ribosomal RNA (rRNA) tRNA binding sites P site A site Large subunit Small subunit
Translation Initiator tRNA • Complex formation: • Ribosome • mRNA • Initiator tRNA • Translation factors mRNA Start codon
Translation • Codon Recognition: • Another tRNA • Translation factors Initiator tRNA mRNA Anticodon Start codon
Translation • Peptide Bond Formation:
Translation • Translocation: New peptide bond mRNA movement
Translation • Elongation:
Codon recognition ELONGATION Stop codon Peptide bond formation Translocation
Transcription Polypeptide Nucleus DNA mRNA RNA processing Termination mRNA Enzyme Elongation ATP Initiation of translation Amino acid attachment
Mutations • A mutation is any change in the nucleotide sequence of DNA. • Mutations can change the amino acids in a protein. • Mutations can involve: • Large regions of a chromosome • Just a single nucleotide pair Normal hemoglobin DNA Mutant hemoglobin DNA mRNA mRNA Sickle-cell hemoglobin Normal hemoglobin