RNA and Protein Synthesis

Write these terms in your journal Ribosome — makes proteins Ribosome — makes proteins RNA polymerase — enzyme that puts together RNA RNA polymerase — enzyme that puts together RNA Promoter —the gene on DNA to which RNA polymerase binds and transcription begins Promoter —the gene on DNA to which RNA polymerase binds and transcription begins Amino acid — monomers of proteins Amino acid — monomers of proteins Polypeptide — protein Polypeptide — protein Genes — sections of DNA that code for something Genes — sections of DNA that code for something

What is RNA? RNA: Ribonucleic Acid RNA: Ribonucleic Acid Usually single-stranded Usually single-stranded Monomers are nucleotides (like DNA) Monomers are nucleotides (like DNA) Contains base, ribose (sugar), and one phosphate Contains base, ribose (sugar), and one phosphate Bases: A, U, C, G ( U = Uracil ) Bases: A, U, C, G ( U = Uracil )

3 Types of RNA rRNA: ribosomal RNA—makes up ribosome rRNA: ribosomal RNA—makes up ribosome Makes the proteins and works with tRNA Makes the proteins and works with tRNA mRNA: messenger RNA—in the nucleus mRNA: messenger RNA—in the nucleus The messenger from DNA to rest of the cell The messenger from DNA to rest of the cell tRNA: transfer RNA—in the cytoplasm tRNA: transfer RNA—in the cytoplasm Transfers amino acids to the ribosome to make proteins Transfers amino acids to the ribosome to make proteins

Protein Synthesis Making proteins Making proteins 2 main steps: 2 main steps: Transcription — written in same “language”. DNA (nucleic acid) to mRNA (nucleic acid) Transcription — written in same “language”. DNA (nucleic acid) to mRNA (nucleic acid) Translation —put in a different “language”. mRNA (nucleic acid) to protein Translation —put in a different “language”. mRNA (nucleic acid) to protein

TRANSCRIPTION Cont’d OCCURS IN NUCLEUS OCCURS IN NUCLEUS (because DNA cannot leave the nucleus!) (because DNA cannot leave the nucleus!) RNA Bonding Rules (A) Adenine = (U) Uracil (G) Guanine = (C) Cytosine

TRANSCRIPTION Cont’d RNA polymerase binds to the promoter, then starts bonding nucleotides to make the RNA strand RNA polymerase binds to the promoter, then starts bonding nucleotides to make the RNA strand There is a gene on DNA that codes for RNA polymerase to stop There is a gene on DNA that codes for RNA polymerase to stop

TRANSCRIPTION RNA DNA RNA polymerase Adenine (DNA and RNA) Cystosine (DNA and RNA) Guanine(DNA and RNA) Thymine (DNA only) Uracil (RNA only)

RNA SPLICING mRNA has to be proofread because parts of it do not code for anything. This process is called RNA splicing. mRNA has to be proofread because parts of it do not code for anything. This process is called RNA splicing. Introns: parts of the mRNA strand that are useless and are taken OUT of the mRNA strand Introns: parts of the mRNA strand that are useless and are taken OUT of the mRNA strand Exons: parts of mRNA that code for proteins and are left IN the mRNA strand Exons: parts of mRNA that code for proteins and are left IN the mRNA strand

CODONS and ANTICODONS Codon: 3 nucleotide sequence of mRNA Codon: 3 nucleotide sequence of mRNA Anticodon: 3 nucleotide sequence of tRNA that is complimentary to mRNA Anticodon: 3 nucleotide sequence of tRNA that is complimentary to mRNA Example: Example: AUG-CGG (codons) AUG-CGG (codons) UAC-GCC (anticodons) UAC-GCC (anticodons) START CODON: AUG START CODON: AUG

TRANSLATION OCCURS IN THE CYTOPLASM ON A RIBOSOME OCCURS IN THE CYTOPLASM ON A RIBOSOME “translates” nucleic acids to amino “translates” nucleic acids to amino acids acids mRNA is read by ribosome mRNA is read by ribosome Ribosome “translates” message (mRNA) to protein Ribosome “translates” message (mRNA) to protein tRNA brings corresponding amino acid to ribosome tRNA brings corresponding amino acid to ribosome Ribosome bonds amino acids together (peptide bonds) Ribosome bonds amino acids together (peptide bonds)

TRANSLATION Cont’d When the amino acid chain lengthens, this is called elongation. When the amino acid chain lengthens, this is called elongation. Translation stops when the ribosome reads a stop codon (UAG, UAA, or UGA) Translation stops when the ribosome reads a stop codon (UAG, UAA, or UGA)

TRANSLATION

TRANSLATION

DNABOTHRNA Double strand Nucleotides: (phosphate, sugar, base) Single strand Base: T Bases: A, C, G Base: U DeoxyriboseSugarRibose DNA polymerase Requires enzymes to make molecules RNA polymerase Made by replication Hydrogen and covalent bonds Made by transcription Codes for the organism Used to make proteins

Videos Replication, Transcription, and Translation Rq5C3K8&feature=related Rq5C3K8&feature=related Rq5C3K8&feature=related Rq5C3K8&feature=related DNA Translation ndscreen&v=TfYf_rPWUdY ndscreen&v=TfYf_rPWUdY ndscreen&v=TfYf_rPWUdY ndscreen&v=TfYf_rPWUdY

Can you identify the following in this diagram?: DNA, mRNA, tRNA, rRNA

Were you right? rRNA

Can you identify the following in this diagram?: mRNA, tRNA, rRNA, amino acids, proteins

Were you right? rRNA