Qhov sib txawv tseem ceeb ntawm kev hloov pauv ntawm cov noob caj noob ces yog qhov transcriptional gene silencing yog cov kev cai ntawm cov noob qhia ntawm qib transcriptional thiaj li yuav txo tau RNA synthesis los ntawm kev txhawb nqa ntsiag to thaum posttranscriptional gene silencing yog cov kev cai ntawm noob qhia ntawm kev txhais lus. qib los ntawm ib ntus tshwj xeeb RNA degradation.
Gene silence yog txheej txheem ntawm kev tswj cov noob qhia los ntawm kev cuam tshuam lossis cuam tshuam cov noob qhia. Nws hloov tawm qee yam ntawm cov noob. Yog li ntawd, nws tiv thaiv kev tsim cov protein los ntawm nws cov noob sib raug. Gene silencing tuaj yeem tshwm sim thaum sau ntawv lossis txhais lus. Yog li ntawd, muaj ob hom gene silencing li transcriptional gene silencing thiab posttranscriptional gene silencing. Transcriptional gene silencing txo qis RNA synthesis thaum posttranscriptional gene silencing degrades mRNA. Ntxiv mus, transcriptional gene silencing tshwm sim nyob rau hauv lub nuclei thaum posttranscriptional gene silencing tshwm sim nyob rau hauv lub cytoplasm.
Dab tsi yog Transcriptional Gene Silence?
Kev hloov pauv noob caj ces yog gene silencing uas ua haujlwm los ntawm kev txo qis RNA synthesis. Nws yog qhov tshwm sim ntawm kev hloov kho histone, tsim kom muaj ib puag ncig uas tsis tuaj yeem nkag mus rau cov tshuab luam ntawv transcriptional. Qhov no tshwm sim hauv cov nuclei ntawm cov hlwb. DNA methylation yog ib qho tseem ceeb heev rau transcriptional gene silencing vim hais tias cov methylation ntawm promotive sequence tshwm sim thaum lub transcriptional gene silencing. Methylation ntawm coding sequence tsis cuam tshuam rau kev sau ntawv. Tab sis, methylation ntawm kev txhawb nqa ib ntus ua rau kev txhawb nqa tsis ua haujlwm vim yog histone deacetylation thiab chromatin condensation. Thaum cov neeg txhawb nqa tau ntsiag to, nws cuam tshuam txog kev hloov pauv cov noob. Li no, hauv transcriptional gene silencing, cov neeg txhawb nqa tau ntsiag to txhawm rau tswj hwm cov noob qhia ntawm qib transcriptional.
Daim duab 01: Gene Silence
Posttranscriptional Gene Silencing yog dab tsi?
Posttranscriptional gene silencing, tseem hu ua RNA silencing lossis RNA cuam tshuam, yog ib hom gene silencing uas ua haujlwm los ntawm kev sib txawv ntawm kev degradation ntawm RNA. Txawm hais tias qhov kev hloov pauv ntawm cov noob tsis cuam tshuam, cov protein synthesis los ntawm mRNA nres vim tsis ruaj khov lossis tsis tuaj yeem siv tau mRNA. Posttranscriptional gene silencing yog induced los ntawm txhob txwm tsim tawm ntawm ob-stranded RNA. Ob-stranded RNA ua rau lub cleavage ntawm homologous mRNA. Me me cuam tshuam RNAs uas muaj homologous sequences rau transcribed cheeb tsam ntawm cov noob coj cov kab ke-kev degradation ntawm mRNA. RNAi khi rau qhov sib ntxiv ntawm lub hom phiaj mRNA thiab cim npe rau degradation.
Daim duab 02: Posttranscriptional Gene Silencing
Posttranscriptional gene silencing muaj ntau daim ntawv thov, suav nrog kev kho noob thiab kho mob qog noj ntshav. Posttranscriptional gene silencing yog ib qho ntawm cov txheej txheem tiv thaiv ntuj hauv cov nroj tsuag tiv thaiv cov kab mob RNA. Yog li ntawd, cov nroj tsuag uas yog posttranscriptional gene silencing defective yog ntau kis tau tus kab mob los ntawm RNA viruses.
Dab tsi yog qhov zoo sib xws ntawm Transcriptional thiab Posttranscriptional Gene Silencing?
- Lawv yog ob qhov sib txawv ntawm noob caj noob ces.
- Ob qhov xwm txheej tuaj yeem raug ntxias los ntawm dsRNA.
- Rau ob hom kev ntsiag to, pom cov tsiaj me me RNA, uas xav tias yog dsRNA cov khoom lwj.
- Lawv muaj feem cuam tshuam nrog.
Dab tsi yog qhov txawv ntawm Transcriptional thiab Posttranscriptional Gene Silencing?
Kev hloov pauv noob caj ces yog qhov tshwm sim ntawm cov noob uas ua haujlwm nyob rau theem kev hloov pauv los ntawm kev txo qis RNA synthesis. Ntawm qhov tod tes, posttranscriptional gene silencing yog ib qho gene silencing phenomenon uas tshwm sim ntawm kev txhais lus ntawm ib theem zuj zus ntawm mRNA. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm transcriptional thiab posttranscriptional gene silencing.
Ntxiv mus, transcriptional gene silencing tshwm sim nyob rau hauv lub nuclei thaum posttranscriptional gene silencing tshwm sim nyob rau hauv lub cytoplasm. Tsis tas li ntawd, cov neeg txhawb nqa tsis ua haujlwm nyob rau hauv transcriptional gene silencing thaum cov neeg txhawb nqa tau ua haujlwm hauv posttranscriptional gene silencing.
Hauv qab infographic tabulates ntau qhov sib txawv ntawm transcriptional thiab posttranscriptional gene silencing.
Summary – Transcriptional vs Posttranscriptional Gene Silencing
Cov noob yog tswj hwm ntawm qib kev sau lossis qib tom qab. Transcriptional gene silencing tshwm sim nyob rau hauv lub nuclei ntawm kev txhawb nqa sequence methylation thiab hloov histone. Yog li ntawd, RNA synthesis txo. Posttranscriptional gene silencing tshwm sim nyob rau hauv lub cytoplasm los ntawm lub cleavage ntawm mRNA thiab inhibition ntawm kev txhais lus. Ob qhov xwm txheej no raug ntxias los ntawm dsRNA thiab nyob ntawm qhov cuam tshuam me me RNAs. Yog li, qhov no qhia txog qhov sib txawv ntawm transcriptional thiab posttranscriptional gene silencing.
