21 - Translation - The professor\'s name was Guang Yao. This is for exam two. PDF

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The professor's name was Guang Yao. This is for exam two....

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Sunday ,May2,y

MCB304 Translation

-Tr ans l at i on •mRNAandt RNAi nt er actt hr oughc odon/ ant i c odonbas epai r i ng •Postt r ans cr i pt i onalmodi fi c at i on( deami nat i on)t oadenos i nechangesi tt oi nos i ne •Eukar y ot i ct r ans l at i onoc cur si nt hec y t opl as m -Somer i bos omesar ef r eefloat i ngands y nt hesi z edpr ot ei nsst ayi nt hec y t os ol -Ot herr i bos omesar eas s oc i at edwi t ht heER,andt hos enewl ys y nt hes i z edpr ot ei nsar er el easedi nt ot heERands entt oot heror ganel l esorf ors ec r et i on

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May2,y

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t RNA

•Adaptgenet i ci nf or mat i oni nmRNAt ot hei rc or r es pondi ngami noaci d •Haveant i c odonst hatcompl ementt het r i pl etc odonsi nmRNA •Car r yt hec or r espondi ngami noac i datt he3’ OH •t RNAsar esmal li ns i z e( 7590nuc l eot i des) ,v er yst abl e,andar ei dent i c ali nbot h pr ok ar y ot esandeukar y ot es

•Char gi ng/ ami noac et yl at i on:c hemi cal l yl i nk i ngt RNAst ot hei rr es pect i v eami no ac i ds

-Ami noac i dcar r i edbyeac ht RNAi sspec i fi edbyi t sant i codon

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-20speci fict RNAs y nt het as es( onef oreac hami noac i d) •61codonscodef or20ami noaci ds •Thi r dbas ei sof t eni r r el ev antf orspec i f y i nganami noac i d( wobbl epos i t i on) •Notal lc odonshav et hei rownt RNA -Mi ni mum numberofant i c odonsf oral l ofac er t ai ncodoni st wo( i nbac t er i a)

-Mi ni mum numberofant i c odonsf oral l codonsi nbac t er i ai s31 -Ri bos ome •Lar ges ubuni t+s mal ls ubuni t=monos ome •Svedber gc oeffici ent :sedi ment at i oncoeffic i enti ns uc r os egr adi ent sr efl ect i ngt he dens i t y ,mas s,ands hapeofapar t i c l e( notaddi t i v e)

•Onebact er i alcel lhasabout10, 000r i bos omesandeuk ar y ot i ccel l shav eal otmor e •RNAi st her ealpl ay eri nt her i bos omedur i ngt r ansl at i on

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•I nt er f ac ebet weent hes mal landl ar ges ubuni t s( wher epol y mer i z at i onofami no ac i dsoc cur s)i sc omposedofRNA

•Ri bos omalpr ot ei nsar emost l yper i pher al( suppor t i ngr ol es) •mRNAbi ndst ot hes mal l subuni t •I ni t i at i on -Pr okar y ot es •Shi neDal gar no( SD)s equenc e -AGGAG( GU) -Ri bos omalbi ndi ngsi t e -I nt er act swi t ht he16Sr RNA •mRNAandI F1bi ndt ot hes mal ls ubuni t •I F2andI F3bi ndt ot hecompl ex -Enhancet hebi ndi ngoft RNA( f met )t ot hesmal ls ubuni tatt hePs i t e •I ni t i at ort RNA( f met )bi ndst omRNAcodoni nPs i t e -f Met( f or my l met hi oni ne)i samodi fi edami noac i di ns er t edatt hefir stpos i t i oni napol y pept i dec hai ni npr okar y ot es

•Lar ges ubuni tbi ndst ocompl ex ,I Ff ac t or sar er el eas ed,andEFTubi ndst o t RNAt of ac i l i t at eent r yi nt ot heAsi t e

-Eukar y ot es •Ri bos omebi ndst o3’c apands cansmRNAunt i li tfindst hefi r s tAUG •Kozaksequence( Rc cAUGG)hel pst r ansl at i oni ni t i at i onbyi nt er act i ngwi t ht he i ni t i at ort RNA

•UsesMet( i ns t eadoff Met )f ort hefir s tami noac i d •El ongat i on 4

Sunday ,May2,y

-Newpept i debondf or medatt heAs i t eandt r ans f er r ed( wi t ht hel i nk edt RNA)t o t hePs i t e

-Smal ls ubuni t“ dec odes ”t het r i pl et spr esenti nmRNA -Lar ges ubuni tr espons i bl ef orpept i debonds y nt hes i s -Requi r ess ev er al el ongat i onf ac t or saswel lasener gyder i v edf r om hy dr ol y s i sof GTP

-Rat eoft r ans l at i oni nbact er i a( 20ami noac i ds / sec ond)i ssi mi l art ot her at eof t r ans c r i pt i on( 4550bas es / s econd)

-Onceanami noac i dc hai nofabout30ami noac i dsi sass embl ed,i temer ges t hr oughat unnel i nt hebas eoft hel ar ges ubuni t

-Pr oof r eadi ng •Ef TuGTPbi ndst ot RNAhel psbr i ngt RNAt ot heAs i t ebuti nhi bi t spept i de bondf or mat i on

•Cor r ectant i c odonc odonpai r i ngt r i gger sGTPhy dr ol y s i s -EFTuGTP>EFTuGDP( EFTusaGTPase) •EFTuGDPl eav est RNAandt RNAc annowfinal l ypar t i c i pat ei npr ot ei ns y nt hesi s

-EFTui nt r oduc esanecess ar ydel aybet weent RNAbi ndi ngandpr ot ei ns y nt hesi st oensur ec or r ec tbas epai r i ngbet weent RNAandmRNA

•Makes1mi st ak eper10^ 4ami noac i ds -Eukar y ot i ct r ans l at i oni sunc oupl edf r om t r ansc r i pt i onbutwi t ht hes amedi r ect i onal i t y

•Ter mi nat i on -I nt heAs i t eappear sas t opcodonwhi c hdoesnots pec i f yanami noaci dt hat doesnotcal lf orat RNA

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-GTPdependentr el easef act or sbi ndt ot heAs i t eandc l eav et hepol ypept i de c hai nf r om t het RNAi nt hePs i t e

-Thecompl exdi s soc i at es -Pol y s ome/ pol y r i bos ome •mRNAwi t hmul t i pl er i bos omest r ans l at i ngs i mul t aneous l y

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