From gene to protein

DNA PhenotypeRNAReplication Transcription

*Transcription

Translation

*Translation

*Gene

The flow of information:1. Storage2. Replication3. Expression

DNA as the Genetic Material

Protein

2. Replication

Review nucleotide structure:

Structural analysis of DNA

DNA Replication and Synthesis

•Complementarity

•”It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism … “

•Mode of DNA Replication

Semiconservative

*Overview: DNA replication

*Complementarity determines which nucleotide will be added

*Chain elongation in a 5’-to-3’ direction

Initiation

*Primase

*Strands must separate•Helicases•SSBPs•DNA gyrase

*Two strands of a double helix are antiparallel

•Continuous DNA synthesis = leading•Discontinuous DNA synthesis = lagging

A large team of enzymes carry out DNA replication:

•Helicases

•SSBPs

•DNA gyrase

Elongation:

•Association of polymerase

•Sliding clamp

•Primase

•DNA synthesis (DNA pol)

•Primer removal and replacement (DNA pol)

•Ligase closes the gaps

The Molecular Basis of Heredity

The Flow of Genetic Information in the Cell

The Genetic Code