The Central Dogma

1
The Central Dogma
Information flow in cells
Language
DNA
The cat sat on the mat
Transcription
THE CAT SAT ON THE MAT
RNA
Translation
Protein
Le chat sest assis sur le petit tapis
2
Why DNA is the genetic material

• Can be replicated accurately
• Has capacity to carry information to direct
  organisation and metabolism in cells
• Can undergo mutation to enable change and
  evolution
• Averys 1944 study proved DNA genes

3
Size shape of genomes
4
Prokaryotic gene organisation
Gene 1
RNA
Protein 1
(Polycistronic)
Promoter
Gene 1
Gene 2
RNA
Proteins 1 and 2
5
Eukaryotic gene organisation
Promoter
Exon1
Intron 1
Exon2
Intron 2
Exon 3
Primary RNA transcript
splicing
mRNA
Protein
6
Simplicity and complexity

• Genes code for proteins (simple)
• Genes cause phenotypes (complex)
• Pleiotropy one gene affects gt1 trait
• Epistasis one trait is affected by gt1 gene
• Interactions between genes environment

7
Summary of next 4 lectures

• DNA is replicated when cells divide
• DNA is transcribed into RNA
• RNA is translated into protein
• Gene expression is regulated
• All this is covered (in more detail) in course
  BC2003