Yuav ua li cas thaum mRNA ua?
Yuav ua li cas thaum mRNA ua?

Video: Yuav ua li cas thaum mRNA ua?

Video: Yuav ua li cas thaum mRNA ua?
Video: Thaum Ntsib Kev Nyuaj Sab Yuav Ua Le Caag | Nruag Hawj 2024, Kaum ib hlis
Anonim

RNA splicing yog kev tshem tawm ntawm introns thiab koom nrog exons hauv eukaryotic mRNA . Nws kuj tshwm sim hauv tRNA thiab rRNA. Splicing yog ua tiav nrog kev pab ntawm spliceosomes, uas tshem tawm introns los ntawm cov noob hauv RNA. Lawv Ameslikas hu ua introns 'junk DNA.

Sib piv, mRNA ua dab tsi?

Eukaryotic mRNA precursors yog ua tiav los ntawm 5 'capping, 3' cleavage thiab polyadenylation, thiab RNA splicing kom tshem tawm introns ua ntej raug thauj mus rau cytoplasm qhov twg lawv tau txhais los ntawm ribosomes. Nascent ua ntej mRNA Cov ntawv sau tseg tau cuam tshuam nrog cov chav kawm ntawm ntau RNA-binding proteins hu ua hnRNP proteins.

Kuj Paub, muaj dab tsi tshwm sim hauv kev ua ntej mRNA? Eukaryotic ua ntej - mRNAs feem ntau suav nrog intros. Introns raug tshem tawm los ntawm RNA ua nyob rau hauv uas lub intron yog looped tawm thiab txiav tawm ntawm exons los ntawm snRNPs, thiab cov exons yog spliced ua ke los tsim lub translatable. mRNA . Qhov tshwm sim mature mRNA Tej zaum yuav tawm ntawm lub nucleus thiab muab txhais rau hauv cytoplasm.

Ua kom pom qhov no, cov kauj ruam ntawm kev ua mRNA yog dab tsi?

Peb qhov tseem ceeb tshaj plaws cov kauj ruam ntawm pre- mRNA kev ua haujlwm yog qhov sib ntxiv ntawm stabilizing thiab signaling yam tseem ceeb ntawm 5' thiab 3' kawg ntawm cov molecule, thiab tshem tawm ntawm intervening sequences uas tsis qhia meej cov amino acids tsim nyog. Muaj tsawg zaus, cov mRNA transcript tuaj yeem "edited" tom qab nws tau sau.

Yuav ua li cas rau mRNA tom qab ua tiav?

"Lub neej voj voog" ntawm ib mRNA hauv eukaryotic cell. RNA yog transcribed nyob rau hauv lub nucleus; tom qab ua tiav , nws raug thauj mus rau cytoplasm thiab txhais los ntawm ribosome. Thaum kawg, tus mRNA yog degraded.

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