Qhov Tseem Ceeb Qhov txawv - Eukaryotic vs Prokaryotic Promoters
Kev txhais lus yog txheej txheem ntawm kev hloov pauv cov ntaub ntawv caj ces khaws cia hauv cov txheej txheem DNA coding rau hauv mRNA ntu. Ib cheeb tsam tshwj xeeb ntawm DNA nyob rau ntawm 5 'kawg ntawm chav transcriptional pib txheej txheem no. Lub cheeb tsam ntawd yog lub npe hu ua cheeb tsam txhawb nqa. Cov neeg txhawb nqa no feem ntau pom nyob ib sab ntawm qhov chaw pib sau ntawv. Qhov ntev ntawm tus txhawb nqa nws txawv ntawm 100 bp rau 1000 bp. Promoters txawv raws li hom kab mob. Eukaryotic thiab prokaryotic cov neeg txhawb nqa yog qhov sib txawv ntawm ib leeg. Hauv prokaryotes, tsuas yog peb hom kev txhawb nqa ib ntus pom muaj xws li, -10 tus txhawb nqa, -35 tus txhawb nqa thiab cov khoom ntws. Hauv eukaryotes, muaj ntau yam kev txhawb nqa sib txawv xws li TATA lub thawv, cov khoom pib, GC lub thawv, CAAT lub thawv, thiab lwm yam.
Eukaryotic Promoters yog dab tsi?
Peb qhov tseem ceeb; core promoter, proximal promoter thiab distal promoter, collectively form a promoter. Hauv cov ntsiab lus ntawm eukaryotes, muaj ntau tus naj npawb ntawm cov neeg txhawb nqa tau pom tias muaj kev txawj ntse thiab muaj ntau hom kev txhawb nqa. Nws tau pom tias, vim qhov nyuaj ntawm cov neeg txhawb nqa eukaryotic, DNA muaj peev xwm rov qab rau nws tus kheej. Qhov no kuj piav qhia txog qhov tseeb tias, cov txiaj ntsig ntawm ntau qhov kev tswj hwm tau tshwm sim txawm tias lawv nyob ntau kilobases deb ntawm qhov chaw ntawm kev sau ntawv. Cov neeg txhawb nqa eukaryotic no muaj peev xwm nthuav dav los ntawm ntau yam DNA sib lawv liag.
Daim duab 01: Eukaryotic Promoter
Piv txwv rau qee tus neeg txhawb nqa eukaryotic yog Pribnow lub thawv (TATA lub thawv), GC lub thawv, CAAT lub thawv thiab lwm yam. Nyob rau hauv cov ntsiab lus ntawm TATA lub thawv, nws yog ib ntus ntawm 5' – TATAA -3' uas muaj nyob rau hauv cov tub ntxhais. txhawb cheeb tsam. Rau lub thawv TATA, cov khoom siv hloov pauv cov protein thiab histone proteins raug khi. Kev sib khi ntawm cov protein ntau ntawm cov khoom siv rau TATA lub thawv pab hauv kev sib txuas ntawm RNA polymerase, uas tom qab ntawd ua rau tsim cov kev hloov pauv. Hauv cov ntsiab lus yooj yim, kev khi ntawm cov proteins no yuav tsav cov txheej txheem ntawm kev sau ntawv. Cov txheej txheem no yuav raug inhibited thaum histone proteins tau khi rau TATA lub thawv. Yog li ntawd, lub thawv TATA yog ib qho tseem ceeb txhawb nqa uas koom nrog hauv kev tswj hwm tus nqi ntawm eukaryotic transcription.
Prokaryotic Promoters yog dab tsi?
Nyob rau hauv cov kab mob prokaryotic, tus txhawb nqa uas koom nrog hauv kev sau ntawv yog txheeb xyuas los ntawm qhov cuam tshuam hu ua sigma factor. Sigma yam tseem ceeb yog tshwj xeeb rau cov kev txhawb nqa sib txawv. Yog li ntawd, nws tau hais tias txhua qhov kev sib koom ua ke yuav paub txog ib qho kev txhawb nqa ib ntus. Qhov no yog ib tug tshwj xeeb yam ntxwv uas muaj nyob rau hauv lub prokaryotic transcription txheej txheem. Ob leeg RNA polymerase thiab sigma yam sib sau ua ke txheeb xyuas thaj chaw txhawb nqa kom raug thiab tsim cov kev hloov pauv.
Tus neeg txhawb nqa prokaryotic tsuas muaj peb hom kev txhawb nqa. Qhov kev koom tes tsawg dua ntawm kev txhawb nqa cov ntsiab lus hauv prokaryotes yog qhov laj thawj tseem ceeb vim li cas lawv cov txheej txheem kev hloov pauv tsis tshua muaj txiaj ntsig thaum piv nrog eukaryotic transcription uas suav nrog ntau tus neeg txhawb nqa ntau dua. Tawm ntawm peb lub ntsiab lus txhawb nqa ntawm prokaryotes, muaj ob lub ntsiab lus tseem ceeb ntawm ob lub DNA luv luv. Cov kab ke no raug cais raws li lawv qhov chaw nyob. Lawv yog, -10 tus neeg txhawb nqa lossis lub ntsiab lus (uas yog tam sim no 10bp nce ntawm qhov chaw pib hloov pauv), -35 tus neeg txhawb nqa lossis lub ntsiab lus (uas yog tam sim no 35bp nce ntawm qhov chaw pib transcription).
Daim duab 02: Prokaryotic Promoter
Tus -10 tus txhawb nqa yog sib npaug rau eukaryotic TATA lub thawv lossis Pribnow lub thawv thiab yog ib qho tseem ceeb rau kev pib ntawm kev hloov pauv hauv prokaryotes. Tus neeg txhawb nqa -35 muaj ib ntu uas yog TTGACA uas nquag koom nrog hauv kev tswj hwm tus nqi ntawm prokaryotic transcription.
Dab tsi zoo sib xws ntawm Eukaryotic thiab Prokaryotic Promoters?
- Nyob rau hauv ob hom, cov neeg txhawb nqa tau tswj hwm los ntawm cov txheej txheem DNA sib txawv uas suav nrog kev txhim kho, silencers, insulators thiab ciam teb.
- Cov neeg txhawb nqa yog cov kab ke uas pib sau hauv cov prokaryotes thiab eukaryotes.
- Cov neeg txhawb nqa yog DNA ib ntus.
Qhov txawv ntawm Eukaryotic thiab Prokaryotic Promoters yog dab tsi?
YEukaryotic vs Prokaryotic Promoters |
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| Eukaryotic cov neeg txhawb nqa yog cov txheej txheem tswj hwm uas pib hloov pauv ntawm cov kab mob eukaryotic. | Prokaryotic cov neeg txhawb nqa yog cov txheej txheem tswj hwm uas pib hloov pauv ntawm cov noob prokaryotic. |
| Elements | |
| Prokaryotic txhawb nqa muaj cov ntsiab lus ntws, -10 lub ntsiab lus thiab -35 lub ntsiab. | Eukaryotic txhawb nqa muaj lub thawv Pribnow (TATA lub thawv), CAAT lub thawv, GC lub thawv thiab cov khoom pib. |
Summary – Eukaryotic vs Prokaryotic Promoters
Tus neeg txhawb nqa yog thaj tsam ntawm DNA uas koom nrog kev pib ntawm txoj kev hu ua kev hloov pauv. Cov neeg txhawb nqa no feem ntau pom muaj nyob rau ntawm qhov chaw pib sau ntawv. Peb qhov tseem ceeb uas tsim ib tus neeg txhawb nqa yog cov neeg txhawb nqa tseem ceeb, tus tshaj tawm proximal thiab tus txhawb nqa distal. Hauv cov ntsiab lus ntawm eukaryotes, muaj ntau tus lej ntawm kev txhawb nqa hauv cheeb tsam txhawb nqa uas muaj kev txawj ntse thiab ntau yam ntau dua li cov prokaryotes. Piv txwv ntawm qee qhov kev txhawb nqa eukaryotic yog Pribnow box (TATA lub thawv), GC lub thawv, CAAT lub thawv thiab lwm yam. Hauv prokaryotes, muaj ob lub ntsiab lus tseem ceeb txhawb nqa xws li -10 lub ntsiab lus (uas yog tam sim no 10bp upstream ntawm transcription pib site), -35 ntsiab lus (uas yog tam sim no 35bp upstream ntawm transcription pib site). -10 tus neeg txhawb nqa pib qhov kev hloov pauv, thiab -35 tus txhawb nqa tswj hwm kev sau ntawv. Ob hom kev txhawb nqa yog tswj hwm los ntawm kev tswj hwm DNA sib txawv uas suav nrog kev txhim kho, silencers, insulators thiab ciam teb cov ntsiab lus. Qhov no yog qhov txawv ntawm eukaryotic thiab prokaryotic prokaryotic prokaryotic.
Download the PDF of Eukaryotic vs Prokaryotic Promoters
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 rub tawm PDF version ntawm no: Qhov Sib txawv Ntawm Eukaryotic thiab Prokaryotic tus txhawb nqa
