translation - oregon state universityoregonstate.edu/.../keynotes/34translation.pdf · translation...
TRANSCRIPT
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
Eukaryotes
Nucleus
Cytoplasm
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
EF-Tu
Protection Against Hydrolysis
Elongation
Elongation
Termination
1.BindingofmRNAbysmallsubunit2.Slidingtoidentifystartcodon(Shine-Dalgarno)3.BasepairingofanticodonofinitiatortRNAtoAUGinmRNA(3IFs)4.Bindingoflargesubunit5.EntryofsecondtRNAintoA-site(EF-Tu)6.Peptidebondformation-peptideontRNAinA-site7.Translocation(requiresGTP&EFG)8.ExitofusedtRNA,entryofnewchargedtRNA9.Repeat5-8toSTOPCodon10.Entryofreleasefactorwithwater
TranslationinProkaryotes
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