Qhov Tseem Ceeb - DNA vs RNA Extraction
Kev kawm ntawm DNA thiab RNA yog qhov tseem ceeb txhawm rau nkag siab cov ntsiab lus tseem ceeb ntawm molecular biology, biotechnology, thiab noob caj noob ces. Kev rho tawm cov qauv DNA thiab RNA ntshiab yog qhov tsim nyog txhawm rau ua cov txheej txheem kev sim thaum cov kev tshawb fawb no. Qhov sib txawv tseem ceeb ntawm DNA thiab RNA rho tawm yog tias DNA extraction txheej txheem purifies DNA thaum RNA extraction purifies RNA. DNA extraction txheej txheem muaj peb theem sib txawv: cell lysis thiab catabolism ntawm daim nyias nyias lipids thiab cov proteins, clumping ntawm catabolite los ntawm concentrated ntsev tov thiab nag lossis daus ntawm DNA nrog ethanol. Cov txheej txheem peb kauj ruam yuav muaj ob kauj ruam xaiv tau. RNA purification txheej txheem muaj plaub theem sib txawv: ntxiv ntawm guanidium thiocyanate rau cell lysis, protein denaturation nrog rau ribonucleases, sib cais ntawm RNA los ntawm kev sib ntxiv ntawm chloroform thiab phenol thiab ntxuav ntawm precipitate siv ethanol.
DNA Extraction yog dab tsi?
DNA rho tawm yog txheej txheem lub cev thiab tshuaj lom neeg uas yog siv los ntxuav DNA los ntawm cov qauv. Kev rho tawm DNA yog ib qho tseem ceeb hauv cov ntsiab lus ntawm molecular biology thiab forensic sciences. Cov txheej txheem yog peb theem pib. Thaum pib, cov hlwb ntawm kev txaus siab yuav tsum tau txais. Tom ntej no, cell lysis yog yooj yim kom ua txhaum lub cell membrane, uas qhib lub cell thiab nthuav tawm cov cytoplasm nrog rau DNA. Surfactants lossis lwm yam tshuaj ntxuav tes tuaj yeem siv los ua cov lipids los ntawm cov cell membrane thaum cov proteins tam sim no catabolized los ntawm proteases. Qhov no yog ib kauj ruam xaiv tau. Thaum lub cell yog lysed, clumping ntawm catabolized molecules yog yooj yim los ntawm concentrated ntsev tov. Nws yog ua raws los ntawm centrifugation ntawm cov tshuaj uas cais cov khib nyiab clumps ntawm DNA. Nyob rau theem no, cov DNA sib txawv yog sib xyaw nrog cov reagents thiab ntsev siv thaum lub sij hawm ntawm lub voj voog.
Daim duab 01: DNA rho tawm
Yuav kom ntxuav nws ntxiv, cov kauj ruam hauv qab no tuaj yeem siv. Ib txoj hauv kev yog ethanol nag lossis daus, uas suav nrog kev sib xyaw cov dej khov txias ethanol nrog cov qauv DNA sib cais. DNA yog insoluble nyob rau hauv cawv thiab yog li tsim ib tug pellet vim lub aggregation ntawm DNA molecules ua ke. Sodium acetate tau ntxiv rau hauv cov txheej txheem no txhawm rau txhim kho qib ntawm nag lossis daus los ntawm kev ua kom lub zog ionic. Ntxiv nrog rau ethanol nag lossis daus txheej txheem, phenol-chloroform extraction txheej txheem kuj yuav raug ntxias rau qhov no. Hauv txoj kev no, phenol denatures cov proteins uas muaj nyob hauv cov qauv. Thaum centrifuged, denatured proteins yuav nyob twj ywm nyob rau hauv cov organic theem thaum lub DNA molecules uas tov nrog chloroform yuav nyob rau hauv lub aqueous theem. Chloroform yuav tshem tawm cov phenol residues. Thaum extraction tiav lawm, DNA khaws cia yaj nyob rau hauv TE tsis los yog ultra ntshiab dej.
RNA Extraction yog dab tsi?
RNA purification yog ib txoj kev uas RNA yog purified los ntawm cov qauv lom. Vim muaj cov ribonuclease hauv cov hlwb thiab cov ntaub so ntswg, cov txheej txheem no nyuaj. Ribonuclease enzyme muaj peev xwm degrade RNA sai. Cov tshuaj lom neeg ntawm ribonucleases yog qhov ruaj khov heev, thiab nws nyuaj rau inactivate lawv. Neutralizing cov ribonucleases yog ib qho kev xaiv. Txij li cov enzyme no muaj nyob rau hauv cov hlwb thiab cov ntaub so ntswg, tshwj xeeb cov tswv yim yog tsim rau RNA extraction. Tawm ntawm ntau txoj hauv kev, txoj hauv kev yog Guanidinium thiocynate-phenol-chloroform extraction.
Daim duab 02: RNA Extraction
Cov Guanidinium thiocynate-phenol-chloroform extraction txoj kev nyob ntawm centrifugation thiab theem sib cais. Qhov sib tov yuav tsum tau centrifuged muaj cov qauv aqueous thiab cov kua dej saturated uas muaj phenol thiab chloroform. Thaum centrifuged, cov kev daws teeb meem muaj cov theem aqueous sab saud thiab qis cov organic theem nyob rau hauv nruab nrab pH tej yam kev mob (pH 7-8). RNA yog tam sim no nyob rau hauv aqueous theem. Cov theem ntawm cov organic feem ntau muaj cov proteins yaj hauv phenol thiab lipids yaj hauv chloroform. Tus neeg sawv cev chaotropic (lub molecule uas muaj peev xwm ua txhaum cov hydrogen bonds ntawm dej molecules) ntxiv; Qhov no yog hu ua, guanidinium thiocyanate. Tus neeg sawv cev no muaj peev xwm ua kom cov proteins uas muaj xws li ribonucleases uas tuaj yeem degrade RNA thiab koom nrog hauv cell lysis. Nws tseem cais rRNA los ntawm ribosomal proteins. Cov kauj ruam kawg ntawm RNA purification yog ntxuav cov nag lossis daus ntawm aqueous theem nrog ethanol. RNA kuj tuaj yeem ua kom huv si siv cov kua nitrogen.
Dab tsi zoo sib xws ntawm DNA thiab RNA Extraction?
- Ob txoj kev rho tawm siv cov tshuaj phem xws li phenol thiab chloroform.
- Centrifugation yog ib qho tseem ceeb txheej txheem rau ob txheej txheem.
- Ethanol yog siv los ntxuav cov nag lossis daus thiab kom tau cov DNA lossis RNA purified.
Dab tsi yog qhov txawv ntawm DNA thiab RNA Extraction?
DNA vs RNA Extraction |
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| DNA rho tawm yog txheej txheem uas rho DNA los ntawm cov kab mob lossis cov qauv. | RNA rho tawm yog txheej txheem uas rho RNA los ntawm tus qauv. |
| Cov txheej txheem rho tawm DNA yog tsim los ntawm peb kauj ruam sib txawv nrog ob kauj ruam xaiv. | Cov txheej txheem rho tawm RNA yog tsim los ntawm plaub kauj ruam sib txawv. |
| Reagents | |
| Surfactants, proteases (optional), cawv, chloroform, phenol, sodium acetate yog siv rau DNA extraction. | Guanidium thiocyanate, chloroform, phenol, ethanol yog siv rau RNA extraction. |
Summary – DNA vs RNA Extraction
DNA thiab RNA rho tawm yog qhov tseem ceeb ntawm cov txheej txheem sim rau kev kawm txog molecular biology, noob caj noob ces, thiab biotechnology. Ob txoj kev koom nrog cov reagents zoo sib xws, tab sis RNA extraction siv ib qho tshwj xeeb reagent hu ua Guanidium thiocyanate uas txo cov kev ua ntawm ribonucleases. Qhov no yog qhov txawv ntawm DNA thiab RNA rho tawm.
Download PDF Version of DNA vs RNA Extraction
Koj tuaj yeem rub tawm PDF version ntawm kab lus no thiab siv nws rau offline hom phiaj raws li daim ntawv ceeb toom. Thov download PDF version ntawm no Qhov txawv Ntawm DNA thiab RNA Extraction
