Qhov Tseem Ceeb Qhov txawv - PCR vs DNA Replication
DNA replication yog txheej txheem ntuj tsim nyob rau hauv cov kab mob nyob. Nws suav nrog kev tsim tawm ntawm ob daim ntawv luam ntawm ib qho DNA molecule. DNA replication yog ib qho tseem ceeb heev ntawm kev tsim noob caj noob ces. Cov ntaub ntawv caj ces yog dhau los ntawm niam txiv mus rau cov xeeb ntxwv feem ntau vim muaj peev xwm ntawm DNA replication. Yog li ntawd, nws yog ib qho tseem ceeb txheej txheem uas tshwm sim nyob rau hauv yuav luag tag nrho cov muaj sia nyob. Cov txheej txheem no tshwm sim hauv vivo. Txawm li cas los xij, DNA replication tuaj yeem ua tiav los ntawm txoj hauv kev hauv vitro ib yam nkaus. Polymerase Chain Reaction (PCR) yog ib txoj hauv kev hauv vitro ntawm DNA replication. PCR yog DNA amplification txoj kev ua nyob rau hauv lub chaw soj nstuam. Nws tsim ntau txhiab mus rau tsheej lab ntawm cov ntawv luam ntawm DNA los ntawm kev txaus siab DNA tawg lossis cov noob. Muaj qhov sib txawv ntawm vivo DNA replication thiab PCR. Qhov sib txawv tseem ceeb ntawm ob qho no yog PCR tau ua hauv lub tshuab PCR ntawm qhov ntsuas kub kom tsim tau ntau cov ntawv luam ntawm DNA thaum DNA replication tshwm sim hauv lub cev ntawm lub cev kub kom tsim tau ob daim ntawv luam ntawm ib qho DNA molecule.
YPCR yog dab tsi?
Polymerase Chain Reaction (PCR) yog ib qho hauv vitro DNA amplification txheej txheem uas niaj hnub ua hauv Molecular Biological Laboratories. Txoj kev no tau ua rau kev tsim tawm ntau txhiab mus rau ntau lab luam ntawm ib qho tshwj xeeb nyiam DNA tawg. PCR tau qhia los ntawm Kary Mullis hauv xyoo 1980. Nyob rau hauv cov txheej txheem no, cov khoom txaus siab ntawm DNA tau txais kev pabcuam raws li tus qauv rau kev luam. Lub enzyme hu ua Taq polymerase yog siv los ua DNA polymerase enzyme, thiab nws yuav ua rau cov synthesis ntawm cov strands tshiab ntawm DNA tawg. Primers uas nyob rau hauv PCR sib tov yuav ua hauj lwm raws li cov ntsiab lus pib rau lub fragment extensions. Thaum kawg ntawm PCR cov tshuaj tiv thaiv, ntau daim qauv ntawm DNA tuaj yeem tau.
Txhua cov khoom xyaw uas tsim nyog los ua cov ntawv luam ntawm DNA suav nrog hauv PCR sib xyaw. Lawv yog cov qauv DNA, DNA polymerase (Taq polymerase), primers (rau pem hauv ntej thiab rov qab primers), nucleotides (lub tsev blocks ntawm DNA) thiab tsis. PCR cov tshuaj tiv thaiv yog khiav hauv lub tshuab PCR, thiab nws yuav tsum tau noj nrog PCR sib xyaw kom raug thiab cov kev pab cuam PCR raug. Yog tias cov tshuaj tiv thaiv sib xyaw thiab cov kev pab cuam raug raug, nws yuav tsim cov ntawv luam ntawm ib ntu ntawm DNA los ntawm ib qho me me ntawm DNA.
Nws muaj peb kauj ruam tseem ceeb koom nrog hauv PCR cov tshuaj tiv thaiv uas yog denaturation, primer annealing thiab strand extension. Peb cov kauj ruam no tshwm sim ntawm peb qhov kub sib txawv. DNA tshwm sim raws li ob-stranded helix. Ob txoj hlua txuas nrog hydrogen bonds. Ua ntej amplification, ob-stranded DNA yog sib cais los ntawm muab qhov kub thiab txias. Thaum kub siab, ob-stranded DNA denatured rau hauv ib qho strands. Tom qab ntawd cov primers anneal nrog lub flanking xaus ntawm cov nyiam fragment los yog cov noob ntawm DNA. Primer yog ib qho luv luv ntawm ib leeg-stranded DNA uas yog ntxiv rau qhov kawg ntawm lub hom phiaj sib lawv liag. Forward thiab thim rov qab primers anneal nrog cov hauv paus ntxiv ntawm qhov kawg ntawm qhov kawg ntawm cov qauv DNA denatured ntawm qhov kub thiab txias.
Thaum primers raug muab tshem tawm nrog DNA, Taq polymerase enzyme pib tsim cov txheej txheem tshiab los ntawm kev ntxiv nucleotides uas yog ntxiv rau cov qauv DNA. Taq polymerase yog ib qho hluav taws xob ruaj khov enzyme uas cais tawm ntawm cov kab mob thermophilic hu ua Thermus aquaticus. PCR tsis tswj qhov kev pom zoo rau Taq polymerase kev txiav txim. Peb theem ntawm PCR cov tshuaj tiv thaiv no rov ua dua los tsim cov khoom tsim nyog ntawm PCR. Ntawm txhua qhov tshuaj tiv thaiv PCR, tus lej ntawm DNA daim qauv yog ob npaug. Yog li ntawd, qhov kev nthuav dav nthuav dav tuaj yeem pom hauv PCR. PCR cov khoom tuaj yeem raug soj ntsuam siv gel electrophoresis vim nws tsim cov DNA pom ntawm cov gel thiab nws tuaj yeem ua kom huv rau kev tshawb fawb ntxiv xws li kev sib txuas thiab lwm yam.
Daim duab 01: PCR
PCR yog cov cuab yeej tseem ceeb hauv kev tshawb fawb txog kev kho mob thiab tshuaj lom neeg. Tshwj xeeb tshaj yog nyob rau hauv kev tshawb fawb forensic, PCR muaj txiaj ntsig zoo vim nws tuaj yeem nthuav dav DNA rau kev tshawb fawb los ntawm cov qauv me me ntawm cov neeg ua txhaum cai thiab ua rau cov ntaub ntawv pov thawj DNA. PCR tau siv dav hauv ntau qhov chaw ntawm Molecular biology suav nrog, genotyping, gene cloning, kev hloov pauv, DNA sequencing, DNA microarrays thiab kuaj txiv thiab lwm yam.
DNA Replication yog dab tsi?
DNA replication yog xa mus rau cov txheej txheem uas tsim ob daim ntawv zoo tib yam ntawm DNA los ntawm ib tug DNA molecule. Nws yog ib qho tseem ceeb ntawm cov txheej txheem kev lom neeg. DNA replication tshwm sim nyob rau hauv tag nrho cov kab mob nyob. Lub genome ntawm niam txiv cell yuav tsum tau rov ua dua thiaj li muab cov genome rau hauv tus ntxhais cell. DNA replication txheej txheem muaj peb kauj ruam tseem ceeb hu ua pib, elongation thiab termination. Cov kauj ruam no yog catalyzed los ntawm cov enzymes sib txawv. DNA replication pib los ntawm qhov chaw hu ua keeb kwm ntawm replication nyob rau hauv lub hlwb 'genome. Nyob rau hauv genome, DNA muaj nyob rau hauv ob-stranded daim ntawv. Ob txoj hlua no tau sib cais thaum pib ntawm DNA replication, thiab nws yog ua los ntawm ATP nyob ntawm DNA helicase. Lub unwinding ntawm DNA yog lub ntsiab tshwm sim uas tshwm sim nyob rau hauv lub pib theem. Los ntawm kev siv cais DNA strands raws li cov qauv, DNA polymerase synthesizes cov tshiab complementary strands ntawm lub template strands rau hauv 5' rau 3' kev taw qhia. Qhov no yog cov kauj ruam hu ua elongation. Kev txiav tawm tshwm sim thaum ob qhov kev sib txuas sib txuas sib txuas ua ke ntawm qhov kawg ntawm niam txiv chromosome.
Daim duab 02: DNA Replication
Lwm yam tsis yog DNA polymerase, ntau cov enzymes xws li DNA primase, DNA helicase, DNA ligase thiab Topoisomerase koom nrog DNA replication. Ib qho tshwj xeeb ntawm vivo DNA replication yog tias nws tsim Okazaki fragments. Ib txoj hlua txuas txuas ntxiv tsim thaum lwm cov ntaub ntawv hauv cov khoom me me.
Dab tsi yog qhov zoo sib xws ntawm PCR thiab DNA Replication?
- Nyob rau hauv PCR thiab DNA replication, ob-stranded DNA yog sib cais los ntawm ib leeg.
- Nyob rau hauv ob qho tib si PCR thiab DNA replication txheej txheem, DNA yog theej.
- Ob qho tib si PCR thiab DNA replication txheej txheem tseem ceeb heev.
- Nyob rau hauv ob qho tib si PCR thiab DNA replication txheej txheem, DNA polymerase enzyme koom nrog.
Qhov txawv ntawm PCR thiab DNA Replication yog dab tsi?
PCR vs DNA Replication |
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| PCR yog ib txoj hauv kev hauv vitro ntawm DNA amplification nyob rau hauv uas ntau txhiab mus rau lab daim ntawv luam ntawm DNA raug tsim. | DNA Replication yog txheej txheem ntuj tsim uas tsim ob daim qauv ntawm DNA los ntawm ib qho DNA molecule. |
| PCR muaj peb kauj ruam; denaturation, primer annealing thiab strand extension. | DNA Replication muaj peb kauj ruam; pib, elongation thiab termination. |
| Kev koom tes ntawm Primers | |
| PCR xav tau cov primers cuav. | DNA Replication tsis xav tau cov khoom siv dag zog. Ib qho luv luv ntawm RNA koom nrog hauv DNA replication. |
| Denaturing of Ob-Strands | |
| Ob txoj hlua sib cais los ntawm kev siv qhov kub thiab txias hauv PCR. | Ob txoj hlua sib cais ntawm ib leeg los ntawm enzyme DNA helicase hauv DNA Replication. |
| Enzyme koom nrog | |
| PCR siv Taq polymerase. | DNA Replication siv DNA polymerase. |
| PCR tshwm sim ntawm peb qhov kub sib txawv hauv lub tshuab. | DNA Replication tshwm sim ntawm lub cev kub hauv lub cev ntawm cov kab mob nyob. |
| In vivo lossis In vitro | |
| PCR yog ib txoj hauv kev hauv vitro. | DNA Replication yog ib txoj hauv kev hauv vivo. |
Summary – PCR vs DNA Replication
DNA replication yog txheej txheem ntawm tsim ob daim qauv ntawm DNA los ntawm ib qho DNA molecule. Nws tshwm sim nyob rau hauv tag nrho cov muaj sia nyob txij li thaum nws muaj ib txoj kev muab cov ntaub ntawv caj ces los ntawm niam txiv mus rau cov xeeb ntxwv. Nws muaj peb lub enzymatically catalyzed cov kauj ruam uas yog pib, elongation thiab termination. DNA replication tuaj yeem ua tiav hauv chav kuaj. PCR yog ib txoj hauv kev tsim ntau cov ntawv luam ntawm DNA los ntawm DNA txaus siab. PCR yog ib txwm ua nyob rau hauv molecular biological laboratory vim nws yog ib qho yooj yim txoj kev ntawm tsim cov ntawv luam ntawm DNA. Qhov no yog qhov txawv ntawm PCR thiab DNA replication.
