Yuav ua li cas transcription txiav nyob rau hauv eukaryotes?
Yuav ua li cas transcription txiav nyob rau hauv eukaryotes?

Video: Yuav ua li cas transcription txiav nyob rau hauv eukaryotes?

Video: Yuav ua li cas transcription txiav nyob rau hauv eukaryotes?
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Eukaryotic transcription xaus thaum nws mus txog qhov tshwj xeeb poly A teeb liab ib ntus hauv cov saw RNA loj hlob. Lub cleavage ntawm RNA thiab txuas ntawm ntau A residues nyob rau hauv cov saw loj hlob xaus tus eukaryotic kev hloov pauv . Poly adenylation yog catalyzed los ntawm Poly A polymerase thiab coj los ntawm poly A binding protein.

Hais txog qhov no, yuav ua li cas transcription xaus?

Transcription termination . RNA polymerase yuav khaws cov ntaub ntawv khaws cia kom txog thaum nws tau txais cov cim tseg. Txoj kev xaus kev sau ntawv hu ua kev txiav txim , thiab nws tshwm sim thaum lub polymerase transcribes ib theem ntawm DNA hu ua terminator.

Kuj Paub, qhov kev txiav tawm ntawm kev hloov pauv txawv li cas hauv prokaryotes thiab eukaryotes? mRNAs hauv prokaryotes nyiam muaj ntau txawv Cov noob ntawm ib qho mRNA txhais tau tias lawv yog polycystronic. Kev txiav txim hauv prokaryotes yog ua los ntawm rho-dependent los yog rho-ywj siab mechanisms. Hauv eukaryotes transcription yog xaus los ntawm ob lub ntsiab lus: ib lub teeb liab poly (A) thiab cov nqes qis qis (7).

Ib sab saum toj no, yuav ua li cas transcription txiav tawm hauv eukaryotes?

Cov kev txiav txim ntawm kev sau ntawv yog txawv rau peb qhov sib txawv eukaryotic tshuaj RNA polymerases. Thaum lub 5'-exonulease "catches" rau RNA Polymerase II los ntawm kev zom tag nrho cov overhanging RNA, nws pab tshem tawm cov polymerase los ntawm nws cov DNA template strand, thaum kawg txiav tawm qhov puag ncig. kev sau ntawv.

Vim li cas cov ntawv sau thiab txhais lus sib cais hauv cov hlwb eukaryotic?

Hauv eukaryotes (cov kab mob uas muaj cov kab mob nuclear), DNA tau txais kev rov ua dua thiab kev sau ntawv nyob rau hauv lub nucleus, thiab cov proteins yog tsim nyob rau hauv lub cytoplasm. Yog li ntawd, RNA yuav tsum taug kev hla cov kab mob nuclear ua ntej nws nkag mus txhais lus . Qhov no txhais tau tias transcription thiab translation yog lub cev cais.

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