Molecular Bio

Silent mutation

Different codon for same amino acid

Nonsense mutation

Different codon that stops translation

Missense mutation

Different codon for different amino acids

Codon preference

Changing speed of reading changes final protein shape

RNA poly I

rRNA

RNA poly II

mRNA

RNA poly III

tRNA

Control of gene expression

When genes are turned on and for how long

Housekeeping/constitutive

Genes turned on all of the time

Developmental/tissue specific

Genes turned on during different times or at different places

Inducible

Genes that turn on during a trigger

1. 3’ Poly A tail

2. Intro splicing

3. 5’ cap of modified guanine

Three post-transcriptional modifications

ENCODE project

Encyclopedia of DNA elements and regions controlling gene expression

Primary structure

Amino acid sequence

Secondary structure

Regular folding patterns (alpha helix, beta pleated sheets)

Tertiary structure

3D function determination

Quaternary structure

Only if combining multiple

Glycosylation, proteolytic processing, phosphorylation, methylation, protein targeting

Examples of post-translational modifications

Complimentation

Using a normal gene to fix a defective one

Ribozymes

Catalytic RNA (ex. spliceosomes, telomerase, rRNA)

microRNA

22 nucleotide long sequence that is encoded by 200-250 genes

DNA ligase

“Glue” of genetic engineering

Endonuclease restriction enzyme

“Scissors” of genetic engineering

Palindromic sequence

what does DNA ligase and endonuclease restriction enzyme look for?