translation proteinsynthesis Lecture4mar
translation ismRNA protein
prokaryotes vs evicarnotes
translationoccurs weprocessesof transcription andtranslation arephysicallyseparated
assoonasmrna transcription nucleus
offDNAtemplate
comes translation cytoplasm
translation
requiresmrna ribosome
Frita aminoacyltrnasynthetases initationfactors elongationfactors releasefactors
m adeupofRNA
ribosomes structures siteoftranslation
protein bindwithmrnaandarethe
linksaminoacidstogether intheorderspecifiedbythecodonsof mrna moleculestoformpolypeptide chains
ribosomeensuresthatthe sequence in themrnacodingforamino
acids isreadinsuccessive non
o verlapping
groupsof 3 nucleotides
eachcomposedof 1 3typeso f ribosomalRNAand20sotypeso fribosomalprotein
1 3bindingsitesfortRNA
tRNA transferR NA
performstranslation of eachcodonin themRNAintooneaminoacid
iii iii ii iii iii Iiii
acid miiiiiiaaiiiniioaonuneo.ae
site fort heaminoacid correspondingtotheanticodon
aminoacyltrna synthetases
aminoacyltrna synthetase enzymesattachspecificaminoacids tospecifictrnamolecules
mosto rganismshaveoneaminoacyltrna synthetase foreachamino
acid
aminoacyltrna synthetase catalyzes theformationofthecovalent
bondbetweenthe
aminoacidandtRNA creating a charged tRNA
the anticodon oftRNAbindsto
the corresponding codoninthemrnasequence
thefirstb aseinthecodonin mrnapairsw iththelastbaseintheanticodon
iiiex is iii iii e an
cov Leucine
voa stopcodon
initiationoftranslation
initiationfactorsrecruitt hesmallr ibosomalsubunit mettrna andthenscanthemrna
forthe avo codon whichspecifies methionine met
whenavo is reached thelargeribosomalsubunit joins andtheinitiationfactors arereleased
methioninestartstheaminoend of the newpolypeptidechain
Elongation
aminoacidsare addedoneby one tothe growingpolypeptidechain
energyprovidedbyelongationfactorsboundto Ote
1 WItrnametbound atthe Pepeptionssiteoftheribosome thenext chargedtrnainlinebindstothe acaminoaculssite
2 a reaction p laceinwhichthebona
t akes themettoitstrnaistransferredtotheaminogroup ofthenextaminoacidinline
c onnecting
forming a peptideb ondbetweent hetwoaminoacids
peptidebondformation
iii t.it e ii iiinii f
Ii Iii t.ITna.itt
Eiiineaseatromrisosomeepertiaenearing
4 newtrnabindstotheribosomeandapeptide
b ondisformedb etweenthenext2aminoa cids
translation ismRNA protein
prokaryotes vs evicarnotes
translationoccurs weprocessesof transcription andtranslation arephysicallyseparated
assoonasmrna transcription nucleus
offDNAtemplate
comes translation cytoplasm
translation
requiresmrna ribosome
Frita aminoacyltrnasynthetases initationfactors elongationfactors releasefactors
m adeupofRNA
ribosomes structures siteoftranslation
protein bindwithmrnaandarethe
linksaminoacidstogether intheorderspecifiedbythecodonsof mrna moleculestoformpolypeptide chains
ribosomeensuresthatthe sequence in themrnacodingforamino
acids isreadinsuccessive non
o verlapping
groupsof 3 nucleotides
eachcomposedof 1 3typeso f ribosomalRNAand20sotypeso fribosomalprotein
1 3bindingsitesfortRNA
tRNA transferR NA
performstranslation of eachcodonin themRNAintooneaminoacid
iii iii ii iii iii Iiii
acid miiiiiiaaiiiniioaonuneo.ae
site fort heaminoacid correspondingtotheanticodon
aminoacyltrna synthetases
aminoacyltrna synthetase enzymesattachspecificaminoacids tospecifictrnamolecules
mosto rganismshaveoneaminoacyltrna synthetase foreachamino
acid
aminoacyltrna synthetase catalyzes theformationofthecovalent
bondbetweenthe
aminoacidandtRNA creating a charged tRNA
the anticodon oftRNAbindsto
the corresponding codoninthemrnasequence
thefirstb aseinthecodonin mrnapairsw iththelastbaseintheanticodon
iiiex is iii iii e an
cov Leucine
voa stopcodon
initiationoftranslation
initiationfactorsrecruitt hesmallr ibosomalsubunit mettrna andthenscanthemrna
forthe avo codon whichspecifies methionine met
whenavo is reached thelargeribosomalsubunit joins andtheinitiationfactors arereleased
methioninestartstheaminoend of the newpolypeptidechain
Elongation
aminoacidsare addedoneby one tothe growingpolypeptidechain
energyprovidedbyelongationfactorsboundto Ote
1 WItrnametbound atthe Pepeptionssiteoftheribosome thenext chargedtrnainlinebindstothe acaminoaculssite
2 a reaction p laceinwhichthebona
t akes themettoitstrnaistransferredtotheaminogroup ofthenextaminoacidinline
c onnecting
forming a peptideb ondbetweent hetwoaminoacids
peptidebondformation
iii t.it e ii iiinii f
Ii Iii t.ITna.itt
Eiiineaseatromrisosomeepertiaenearing
4 newtrnabindstotheribosomeandapeptide
b ondisformedb etweenthenext2aminoa cids
