Qhov sib txawv tseem ceeb ntawm chav kawm I thiab chav kawm II hloov pauv cov ntsiab lus yog chav kawm kuv cov ntsiab lus hloov pauv tau yog retrotransposons, thaum chav kawm II cov ntsiab lus hloov pauv tau yog DNA transposons.
Ib lub ntsiab lus transposable yog DNA ib ntus uas tuaj yeem hloov nws txoj haujlwm hauv genome. Qee zaum nws tsim thiab thim rov qab kev hloov pauv. Nws kuj tseem tuaj yeem hloov kho tus kheej caj ces thiab qhov loj ntawm genome ntawm lub xov tooj ntawm tes. Cov txheej txheem no feem ntau ua rau muaj qhov sib npaug ntawm tib yam khoom siv caj ces. Lub ntsiab lus transposable tau pom thawj zaug los ntawm Barbara McClintock, thiab nws yeej qhov khoom plig Nobel rau nws qhov kev tshawb pom hauv xyoo 1983. Cov ntsiab lus hloov tau tuaj yeem muab faib ua ob chav kawm raws li lawv txoj kev hloov pauv hloov pauv: chav kawm I thiab chav kawm II hloov pauv tau.
Class I Transposable Elements yog dab tsi?
Class I transposable ntsiab yog retrotransposons. Retrotransposon yog ib hom kab mob caj dab uas luam tawm thiab muab nws tus kheej tso rau hauv qhov chaw sib txawv los ntawm kev hloov RNA rov qab rau hauv DNA los ntawm cov txheej txheem hu ua thim rov qab. Cov txheej txheem no yog catalyzed los ntawm qhov rov qab transcriptase enzyme. Retrotransposon feem ntau siv RNA hloov pauv nruab nrab. Class I transposable ntsiab feem ntau yog theej hauv ob theem. Ua ntej, lawv tau sau los ntawm DNA rau RNA. Tom qab ntawd cov RNA tsim tawm yog rov qab xa mus rau DNA. Tom qab ntawd, qhov theej DNA no tau muab tso rau hauv lub genome ntawm txoj haujlwm tshiab. Cov yam ntxwv ntawm retrotransposons zoo ib yam li retrovirus xws li HIV.
Daim duab 01: Chav Kawm I Transposable Element
Retrotransposons tuaj yeem muab faib ua peb hom.
- Retrotransposons nrog ntev davhlau ya nyob twg rov ua dua (LTRs), uas encodes rau thim rov qab transcriptase,
- Retrotransposons nrog ntev interspersed nuclear ntsiab (LINE) uas encode rau reverse transcriptase tab sis tsis muaj LTRs thiab yog transcribed los ntawm RNA polymerase II,
- Retrotransposons nrog luv luv interspersed nuclear ntsiab (SINEs) uas tsis encode rau reverse transcriptase thiab yog transcribed los ntawm RNA polymerase III.
Ntxiv mus, vim muaj cov txheej txheem zoo sib xws nrog cov tshuaj retrotransposons, retrovirus tuaj yeem suav tias yog cov khoom sib kis tau.
Clas II Transposable Elements yog dab tsi?
Class II transposable ntsiab yog DNA transposons. Class II transposable cov ntsiab lus muaj kev txiav thiab muab tshuaj txhuam kev hloov pauv uas tsis koom nrog RNA nruab nrab. Kev hloov pauv yog catalysed los ntawm ntau cov enzymes transposase. Cov enzymes no tuaj yeem tshwj xeeb lossis tsis tshwj xeeb khi rau DNA. Transposase ua rau staggered txiav ntawm lub hom phiaj ntawm DNA uas tsim cov nplaum kawg. Tom qab ntawd cov no txiav tawm DNA transposon ligates rau hauv lwm lub hom phiaj.
Daim duab 02: Chav Kawm II Transposable Elements
Feem ntau, DNA polymerase nyob rau hauv qhov tshwm sim ntawm qhov sib txawv ntawm cov nplaum nplaum, thiab DNA ligase kaw cov pob txha qab zib-phosphate. Ntxiv mus, qhov kev hloov pauv no ua rau lub hom phiaj qhov chaw duplication. Cov chaw nkag ntawm DNA transposons tuaj yeem txheeb xyuas los ntawm luv luv, ncaj qha rov ua raws li kev rov ua dua. Tab sis tsis yog txhua tus DNA transposons qhia txog kev txiav thiab muab tshuaj txhuam hloov pauv. Piv txwv li, qee qhov kev hloov pauv hloov pauv hloov pauv uas cov transposons rov ua dua lawv tus kheej mus rau lub hom phiaj tshiab.
Zoo sib xws Ntawm Chav Kawm I thiab Chav Kawm II Hloov Cov Ntsiab Lus
- Class I thiab Class II transposable cov ntsiab lus yog cov noob caj noob ces lossis dhia caj ces.
- Ob leeg tuaj yeem hloov lawv txoj haujlwm hauv genome.
- Lawv yog tsim los ntawm DNA sequences.
- Lawv yog noob caj noob ces qia dub.
- Lawv tseem ceeb heev hauv kev ua haujlwm genomic thiab evolution.
Qhov Sib txawv Ntawm Chav Kawm I thiab Chav Kawm II Hloov Cov Ntsiab Lus
Class I transposable ntsiab yog retrotransposons, thaum chav kawm II transposable ntsiab yog DNA transposons. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm chav kawm I thiab chav kawm II transposable ntsiab. Tsis tas li ntawd, chav kawm I transposable ntsiab siv RNA intermediates hauv kev hloov pauv hloov pauv. Ntawm qhov tod tes, chav kawm II transposable ntsiab siv DNA intermediates hauv kev hloov pauv hloov pauv.
Cov infographic hauv qab no suav nrog qhov sib txawv ntawm chav kawm I thiab chav kawm II cov ntsiab lus sib txuas hauv daim ntawv teev npe rau ib sab ntawm kev sib piv.
Summary – Class I vs Class II Transposable Elements
Cov ntsiab lus Transposable yog lub npe hu ua cov noob caj noob ces lossis cov noob dhia dhia. Lawv yog DNA sequences. Transposable cov ntsiab lus tau muab faib ua ob chav kawm raws li lawv txoj kev hloov pauv raws li chav kawm I thiab chav kawm II hloov pauv tau. Class I transposable ntsiab yog retrotransposons, thaum chav kawm II transposable ntsiab yog DNA transposons. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm chav kawm I thiab chav kawm II hloov pauv tau.
