Qhov sib txawv tseem ceeb ntawm kev hloov pauv thiab txiav thiab muab tshuaj txhuam yog qhov hloov pauv hloov pauv, qhov hloov pauv tau theej mus rau qhov chaw tshiab, thaum txiav thiab muab tshuaj txhuam, qhov hloov pauv hloov mus rau qhov chaw tshiab.
Cov ntsiab lus hloov pauv lossis dhia cov noob yog DNA cov kab ke uas tuaj yeem hloov pauv lawv txoj haujlwm hauv genome. Qhov no yog hu ua transposition. Kev hloov pauv qee zaum tuaj yeem tsim lossis thim rov qab kev hloov pauv, thiab hloov pauv ntawm lub xovtooj ntawm cov noob caj noob ces thiab qhov loj ntawm genome. Kev hloov pauv tau tshawb pom los ntawm Barbara McClintock hauv xyoo 1983. Kev hloov pauv tuaj yeem tshwm sim los ntawm ob txoj kev ua theej thiab txiav thiab muab tshuaj.
Kev hloov pauv yog dab tsi?
Kev hloov pauv hloov pauv yog hom kev hloov pauv hloov pauv uas pab cuam hloov pauv ntawm qhov chaw ib txwm nyob mus rau lwm qhov los ntawm cov txheej txheem rov ua dua lossis theej dua. Cov txheej txheem no tau pom thawj zaug los ntawm James A Shapiro hauv xyoo 1979. Nyob rau hauv cov txheej txheem no, cov khoom hloov pauv tau muab luam tawm thaum lub sijhawm hloov cov tshuaj tiv thaiv kom lub chaw hloov pauv yog ib daim qauv ntawm cov khoom qub. Ntxiv mus, nyob rau hauv no mechanism, tus pub thiab receptor DNA sequences tsim ib tug yam ntxwv nruab nrab "theta" configuration hu ua Shapiro intermediate (cointegrate). Kev hloov pauv hloov pauv yog tus yam ntxwv retrotransposon. Cov txheej txheem no ib txwm tshwm sim hauv chav kawm I transposons.
Daim duab 01: Kev hloov pauv hloov pauv
Ib qho piv txwv zoo ntawm kev hloov pauv tuaj yeem pom hauv E. coli TN3 transposon. TN3 transposon tuaj yeem txav los ntawm thawj plasmid mus rau lwm lub hom phiaj plasmid los ntawm cov txheej txheem rov ua dua lossis theej dua. Tag nrho cov xwm txheej no yog kho los ntawm ob lub enzymes tseem ceeb hu ua transposase thiab resolvase. Tsis tas li ntawd, kev hloov pauv hloov pauv tuaj yeem pom hauv DNA transposons thiab retroposons. Cov kab mob kis tau zoo tshaj plaws uas tau kawm yog tus kab mob bacteriophage Mu.
Kev txiav thiab muab tshuaj txhuam yog dab tsi?
Kev hloov pauv thiab muab tshuaj txhuam yog hom kev hloov pauv hloov pauv uas pab cuam hloov pauv ntawm qhov chaw ib txwm mus rau lwm qhov los ntawm kev txiav thiab muab tshuaj txhuam. Cov txheej txheem no tseem hu ua tus qauv conservative ntawm kev hloov pauv. Hauv qhov kev hloov pauv tsis zoo no, qhov kev txiav tawm thiab kev sib koom ua ke ntawm kev hloov pauv ntawm ib qho chaw genomic mus rau lwm qhov chaw tsis tau tso ib daim ntawv rov qab.
Daim duab 02: Txiav thiab muab tshuaj txhuam
Nyob rau hauv no mechanism, lub transposase enzyme thawj khi rau lub davhlau ya nyob twg rov qab uas feem ntau muaj nyob rau ntawm ob kawg ntawm lub transposons thiab nws ces tsim ib tug qauv hu ua synaptic complex (transpososome). Lub synaptic complex cleaves lub transposon los ntawm nws thawj genomic qhov chaw thiab integrates nws mus rau hauv lub hom phiaj tshiab. Tom qab ntawd, transposases tawm ntawm ob qho kawg ntawm transposon. Thaum lub transposase enzyme tawm hauv lub transposon, qhov khoob yog sau los ntawm tus tswv tsev polymerase enzyme. Qhov no tso cai rau ua tiav kev koom tes ntawm transposon mus rau qhov chaw tshiab genomic. Cov txheej txheem no feem ntau tshwm sim hauv chav kawm II transposons. Tsis tas li ntawd, TN5 cov kab mob transposons yog ib qho piv txwv zoo uas qhia tau hais tias muaj kev saib xyuas lossis txiav thiab muab tshuaj txhuam hloov pauv.
Dab tsi yog qhov zoo sib xws ntawm Kev Hloov Hloov Hloov thiab Txiav thiab Muab Tshuaj Hloov Hloov?
- Kev hloov pauv thiab txiav thiab muab tshuaj txhuam yog ob hom kev hloov pauv hloov pauv.
- Nyob rau hauv ob qho tib si, cov ntsiab lus transposable txav los ntawm ib qho chaw genomic mus rau lwm qhov chaw tshiab genomic.
- Ob lub tswv yim tuaj yeem tsim lossis thim rov qab hloov pauv thiab hloov pauv lub xovtooj ntawm caj ces tus kheej.
- Cov kab mob kis kab mob qhia ob qho tib si.
- Lawv yog cov xwm txheej tseem ceeb heev rau kev hloov pauv.
Dab tsi yog qhov txawv ntawm Kev Hloov Pauv Hloov thiab Txiav thiab Muab Tshuaj Hloov Hloov?
Kev hloov pauv hloov pauv yog hom kev hloov pauv hloov pauv uas qhov hloov pauv hloov mus rau qhov chaw tshiab, thaum txiav thiab muab tshuaj txhuam yog ib hom kev hloov pauv hloov pauv hloov pauv mus rau qhov chaw tshiab. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm kev hloov pauv hloov pauv thiab txiav thiab muab tshuaj hloov pauv. Tsis tas li ntawd, kev hloov pauv hloov ib txwm tshwm sim hauv chav kawm I transposons, thaum txiav thiab muab tshuaj txhuam hloov ib txwm tshwm sim hauv chav kawm II transposons.
Cov hauv qab no infographic nthuav tawm qhov sib txawv ntawm kev hloov pauv hloov pauv thiab txiav thiab muab tshuaj txhuam hloov pauv hauv daim ntawv teev npe rau ib sab ntawm kev sib piv.
Summary – Replicative Transposition vs Cut and Paste Transposition
Kev hloov pauv thiab txiav thiab muab tshuaj txhuam yog ob hom kev hloov pauv hloov pauv. Kev hloov pauv hloov pauv yog ib hom kev hloov pauv hloov pauv uas qhov hloov pauv hloov pauv mus rau qhov chaw tshiab, thaum txiav thiab muab tshuaj txhuam yog ib hom kev hloov pauv hloov pauv hloov pauv mus rau qhov chaw tshiab. Yog li, qhov no qhia txog qhov sib txawv ntawm kev hloov pauv thiab txiav thiab muab tshuaj txhuam.
