Lub luag haujlwm ntawm poly A Tail yog dab tsi?
Lub luag haujlwm ntawm poly A Tail yog dab tsi?

Video: Lub luag haujlwm ntawm poly A Tail yog dab tsi?

Video: Lub luag haujlwm ntawm poly A Tail yog dab tsi?
Video: Xav rov ntsib koj ib zaug dua. 8/8/2018 2024, Kaum ib hlis
Anonim

Muaj nuj nqi . Hauv nuclear polyadenylation , a poly (A) tail ntxiv rau RNA thaum kawg ntawm kev sau ntawv. Hauv mRNAs, lub poly (A) tail tiv thaiv mRNA molecule los ntawm enzymatic degradation nyob rau hauv lub cytoplasm thiab pab nyob rau hauv transcription termination, export ntawm mRNA los ntawm lub nucleus, thiab kev txhais lus.

Tom qab ntawd, ib tug kuj yuav nug, yuav ua li cas yog lub poly A tail ntxiv rau pre mRNA Lub hom phiaj ntawm poly A Tail yog dab tsi?

PAP ntxiv kwv yees li 10 adenine nucleotides mus rau qhov kawg ntawm 3' ua ntej - mRNA molecule. Qhov sib ntxiv ntawm luv poly (A) tail tso cai rau kev khi ntawm cov poly (A) binding protein (PABII) to the qab . PABII nce tus nqi ntawm polyadenylation , uas tom qab tso cai rau ntau PABII protein los khi cov qab.

Tsis tas li ntawd, muaj pes tsawg tus poly A tail? Poly(A) tails ntawm mRNAs muaj qhov pib ntev ntawm 70-80 nucleotides hauv cov poov xab thiab ∼ 250 nucleotides nyob rau hauv mammalian hlwb. Cov tails ntev no muaj qhov ua haujlwm ruaj khov: Thoob plaws hauv lub neej cytoplasmic ntawm mRNA, lawv maj mam luv los ntawm lawv 3 kawg.

Ib tug kuj yuav nug, poly A tail ntxiv li cas?

poly-A tail . Cov poly-A tail yog ib txoj hlua ntev ntawm adenine nucleotides uas yog ntxiv mus rau tus tub txib RNA (mRNA) molecule thaum lub sij hawm RNA ua kom muaj kev ruaj ntseg ntawm cov molecule. Tom qab ntawd ib qho enzyme hu ua poly - Ib qho polymerase ntxiv ib tug saw ntawm adenine nucleotides rau RNA.

Cov kab mob RNA puas muaj poly A tail?

Polyadenylation yog postranscriptional hloov kho ntawm RNA pom nyob rau hauv tag nrho cov cell thiab nyob rau hauv organelles. Hauv kab mob , ib feem me me ntawm RNA chaw nres nkoj oligo (A) qab uas feem ntau luv dua 20 As.

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