DNA & Protein Synthesis

DNA Replication during interphase of the cell cycle during interphase of the cell cycle H-bond break btw complementary base pairs (A-T and C-G) H-bond break btw complementary base pairs (A-T and C-G) strands unwind and pull apart strands unwind and pull apart DNA polymerase brings in new nucleotides DNA polymerase brings in new nucleotides new DNA = old strand + new strand new DNA = old strand + new strand genes = portions of DNA w/info to synthesize a protein genes = portions of DNA w/info to synthesize a protein

Protein Synthesis multi-step, enzyme-catalyzed process multi-step, enzyme-catalyzed process 3 nucleotides code for a specific amino acid 3 nucleotides code for a specific amino acid GGT = glycine GGT = glycine AAA = lysine AAA = lysine others code for the start and stop of protein synthesis others code for the start and stop of protein synthesis TAC = start TAC = start ATC = stop ATC = stop

DNA vs. RNA double strand double strand sugar = deoxyribose sugar = deoxyribose A, T, C, G A, T, C, G nucleus ONLY nucleus ONLY single strand single strand sugar = ribose sugar = ribose U, A, G, C U, A, G, C can travel outside nucleus can travel outside nucleus

Transcription – The Scribe DNA is located within the nucleus, but protein synthesis occurs in the cytoplasm DNA is located within the nucleus, but protein synthesis occurs in the cytoplasm messenger RNA (mRNA) carries a gene’s message out of the nucleus messenger RNA (mRNA) carries a gene’s message out of the nucleus RNA polymerase creates a complementary strand RNA polymerase creates a complementary strand A, T, G, C, G  U, A, C, G, C A, T, G, C, G  U, A, C, G, C mRNA is the template for protein synthesis mRNA is the template for protein synthesis

Translation – The Translator codon – 3-base sequence of mRNA codon – 3-base sequence of mRNA AUG CCC GCU GCU UAG AUG CCC GCU GCU UAG mRNA travels outside nucleus to ribosome where it is translated from the “language” of nucleic acids to the “language” of amino acids  translation mRNA travels outside nucleus to ribosome where it is translated from the “language” of nucleic acids to the “language” of amino acids  translation transfer RNA (tRNA) correctly aligns amino acids to mRNA codons transfer RNA (tRNA) correctly aligns amino acids to mRNA codons anticodon – codon complement anticodon – codon complement

Translation (cont.) peptide bonds hold tRNA’s amino acids together  polypeptide chain peptide bonds hold tRNA’s amino acids together  polypeptide chain controlled by enzymes controlled by enzymes

Transcription/Translation Practice TAC CGG ATG CCA GAT CAA ATC TAC CGG ATG CCA GAT CAA ATC replicate complementary strand? replicate complementary strand? ATG GCC TAC GGT CTA GTT TAG ATG GCC TAC GGT CTA GTT TAG TAC CGG ATG CCA GAT CAA ATC TAC CGG ATG CCA GAT CAA ATC transcribe into mRNA? transcribe into mRNA? AUG GCC UAC GGU CUA GUU UAG AUG GCC UAC GGU CUA GUU UAG translate into tRNA? translate into tRNA? UAC CGG AUG CCA GAU CAA AUC UAC CGG AUG CCA GAU CAA AUC polypeptide? (use mRNA strand) polypeptide? (use mRNA strand) Met – Ala – Tyr – Gly – Leu –Val – Stop Met – Ala – Tyr – Gly – Leu –Val – Stop

THE QUEEN The “Castle” The Scribe Snoop’s House “Ribizzle” Polypeptizzle Message

Protein Synthesis Rap All the mRNA, yo Scribe it like its hot All the tRNA, yo Translate like its hot All my amino acids Bind it like its hot Turning my D-N-A into proteins and I live in the “ribizzle” ‘cuz I’m working for the Queen Hey! Ho! Hey! Ho!