Translation
Dr.KevinAhern
CentralDogma
mRNAStructure
Bacteria
GeneticCode
Universal
Redundant
Logical
Punctuated
64 Codons
3 Stops
1 Start
2 Unique for AA
59 Redundant
TranslationSteps
CentralDogma
Nucleus
Cytoplasm
Eukaryotes
Translation
SimpleViewofTranslation
Start Codon
Stop Codon
Structure
tRNAs-TranslatorMolecules
Amino Acid Attachment Point
tRNAs-TranslatorMolecules
AminoAcidActivation-ChargingoftRNAs
Aminoacyl tRNA-synthetase
Type 1 - AA on 2’ OH
Type 2 - AA on 3’ OH
“Charging”oftRNAs
fMetSynthesisinProkaryotes
WobbleBase
WobbleBase
SmallRibosomalSubunit(30SProkaryotes)
LargeRibosomalSubunit(50SProkaryotes)
Structure
50S Ribosomal Subunit
rRNAs
SimpleOverview
Overview
Prokaryotes-Shine-DalgarnoSequence
Shine-DalgarnoSequence
16S rRNA Sequence
Initiation
Initiation
Structure
Protection Against
Hydrolysis
EF-Tu
Elongation
Elongation
Termination
TranslationinProkaryotes
1.BindingofmRNAbysmallsubunit
2.Slidingtoidentifystartcodon(Shine-Dalgarno)
3.BasepairingofanticodonofinitiatortRNAtoAUGinmRNA(3IFs)
4.Bindingoflargesubunit
5.EntryofsecondtRNAintoA-site(EF-Tu)
6.Peptidebondformation-peptideontRNAinA-site
7.Translocation(requiresGTP&EFG)
8.ExitofusedtRNA,entryofnewchargedtRNA
9.Repeat5-8toSTOPCodon
10.Entryofreleasefactorwithwater
TranslationinEukaryotes
Differences
1. mRNA structure
2. Ribosome sizes (60S & 40S)
3. rRNA sizes (extra rRNA)
4. No Shine-Dalgarno
5. No fMet
TranslationinEukaryotes-Initiation
Kozak Sequences
EukaryoticTranslation
Elongation
EukaryoticTranslation
Bonding to mRNA
Premature
Stopping of
Translation
Degradation of
mRNA
MembraneProteins
Structure
MembraneProteinSynthesis