Learning Objectives

know the broad steps of replication
- Denaturation / unzipping
- Priming (note: NOT annealing)
- Elongation / extension
- Primer Removal
- Ligation
know the enzymes responsible for each step
- Initiator protein - binds ORI and opens
- Helicase - extends bubble
- Single-strand binding protein - keeps strands separated
- Topoisomerase - nicks DNA to relieve coiling
- DNA Polymerase III - extends RNA primer making DNA
- DNA Polymerase I - removes RNA primers and fills in gaps (also proofreading)
- Ligase - connects okazaki fragments
Know what the leading (continuous) and lagging (discontinuous) strands are
Know that genes are represented by arrows representing direction of transcription
Know which strand is the template based on arrow representation
- arrow right, then bottom strand template
- arrow left, then top strand template
Know that the mRNA looks like the coding (non-template) strand
know how to translate an mRNA (or coding DNA) sequence
- Start at 1st AUG
- 1st amino acid always Met (Met can be elsewhere too)
- Every 3 nt is a codon for 1 amino acid
- Stop at stop codon, DON'T write "Stop"
Know the different kinds of mutations
- silent - no amino acid change
- missense - amino acid changed at mutation
- nonsense - amino acid at mutation is changed specifically to a stop codon
- frameshift - inserted or removed nucleotide mutation, changes reading frame. All amino acids after mutation are altered
- frameshift leading to stop

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