Key Terms:
- tRNA
- translation factor
- anticodon loop
- ribosome
- rRNA
- polyribosome
- start codon
- missense mutation
- nonsense mutation
Act 1: Initiation
- initiation factors assemble small unit ribsome, mRNA, initiator tRNA, and large unit ribosome to start synthesis of protein.
- small ribsome attaches to mRNA (5' AUG 3')
- threee binding sites: P(peptide), A(amino acid), & E(exit) site
- P contains tRNA with peptide attached to it
Act 2: Elongation
- A contains tRNA with another amino acid which is added to polypeptide
- tRNA that no longer has amino acid is translocated to E site
- Amino acid continually added to growing polypeptide chain to make a protein
- The amino acids are attached by peptide bonds (covalent)
Act 3: Termination
- stop codons "UAA", "UAG", or "UGA" stop synthesis of protein
- everything dissociates
RNA Molecules:
- mRNA (Messenger) : template for translation
- tRNA (Transfer) : translation of mRNA
- rRNA (Ribosomal) : translation of mRNA
- snRNA (Small unit) : modify mRNA molecule
Key terms:
- "TATA" Box / Promoter region / Upstream
- Initiation complex
- Coding/Sense strand
- Template / Antisense strand
- RNA Polymerase II
- Uracil
- RNA Transcript / pre-mRNA
- Primary RNA
- Splicing
- Spliceosome
- Intron
- Extron
- poly-A-tail
- G-cap
- Transcription factor (protein)
- Ribozyme
- Terminator / "AAA UAA" / Downstream
Act 1: Initiation
- Transcription factors find TATA Box and bind to it.
- RNA Polymerase II locates and binds to the transcription factors which create an initiation complex.
- RNA Polymerase II begins transcription.
Act 2: Elongation
- mRNA transcribed in a 5' to 3' direction
- only one strand is synthesized
- antiparallel to template strand
- Copies coding strand but replaces Thymine with Uracil
- Upstream to Downstream
Act 3: Termination
- Terminator sequence signals end point of synthesis of mRNA
- stop codon or "AAA UAA"
