Cov ntawv sau tseem ceeb hloov pauv li cas?
Cov ntawv sau tseem ceeb hloov pauv li cas?

Video: Cov ntawv sau tseem ceeb hloov pauv li cas?

Video: Cov ntawv sau tseem ceeb hloov pauv li cas?
Video: 1 ເຄັດລັບ tij laug lis Xyooj Mct siv hloov pauv neeg lub neej. 2024, Kaum ib hlis
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Cov thawj cov ntawv sau tseg ntawm RNA synthesized los ntawm RNA polymerase II (mRNA) yog hloov kho nyob rau hauv lub nucleus los ntawm peb qhov txawv txav: qhov sib ntxiv ntawm 5 'cap, qhov sib ntxiv ntawm polyadenylic acid (poly-A) tus Tsov tus tw, thiab qhov kev txiav tawm ntawm cov ntu tsis muaj ntaub ntawv.

Raws li txoj cai, daim ntawv teev npe tseem ceeb yog dab tsi?

A thawj daim ntawv sau tseg yog ib leeg-stranded ribonucleic acid (RNA) khoom tsim los ntawm kev sau ntawv ntawm DNA, thiab ua tiav kom tau txais ntau yam khoom RNA paub tab xws li mRNAs, tRNAs, thiab rRNAs. Cov thawj cov ntawv sau tseg raug xaiv los ua mRNAs raug hloov kho hauv kev npaj rau kev txhais lus.

Tsis tas li ntawd, dab tsi complex yog lub luag hauj lwm rau tshem tawm ib feem ntawm cov thawj transcript? Introns yog tshem tawm los ntawm pre-mRNA los ntawm kev ua haujlwm ntawm a complex hu ua spliceosome. Lub spliceosome yog tsim los ntawm cov proteins thiab RNAs me me uas cuam tshuam rau cov protein-RNA enzymes hu ua me me nuclear ribonucleoproteins lossis snRNPs (hais SNURPS).

Ib yam li ntawd, koj tuaj yeem nug, ua ntej mRNA hloov pauv li cas?

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 thiab txiav tawm ntawm lub 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.

Yog vim li cas nws yog thawj daim ntawv teev lus hauv prokaryotes?

Ib tug 5 'cap yog ntxiv rau lub prokaryotic cov ntaub ntawv tseem ceeb cia lub ribosome pib txhais tam sim ntawd. Cov ntawv sau tseem ceeb nyob rau hauv eukaryotes muaj introns uas yuav tsum tau muab tshem tawm. Prokaryotes tsis muaj lub hnab ntawv nuclear thiab cov ribosome tuaj yeem pib txhais ua ntej kev sau ntawv xaus.

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