Lub luag haujlwm ntawm nucleosome yog dab tsi?
Lub luag haujlwm ntawm nucleosome yog dab tsi?

Video: Lub luag haujlwm ntawm nucleosome yog dab tsi?

Video: Lub luag haujlwm ntawm nucleosome yog dab tsi?
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Nucleosomes yog lub hauv paus packing unit ntawm DNA ua los ntawm histone proteins nyob ib ncig ntawm uas DNA yog coiled. Lawv ua hauj lwm raws li ib tug scaffold rau tsim ntawm siab dua kev txiav txim chromatin qauv raws li zoo raws li rau ib tug txheej ntawm kev tswj ntawm noob qhia.

Kuj nug, dab tsi yog qhov haujlwm ntawm nucleosomes quizlet?

Nucleosomes tau tsim los ntawm DNA qhwv ib puag ncig keeb kwm keeb kwm hauv cov qauv uas yog thoob ntiaj teb hauv cov hlwb eukaryotic. Lawv pom tseeb muaj nuj nqi kom txo tau tag nrho ntev ntawm DNA nyob rau hauv lub nucleus, yog li pab kom lub chromatin koom.

Ib qho ntxiv, daim ntawv nucleosome zoo li cas? Cov nucleosome yog qhov tsawg tshaj plaws qauv ntawm chromatin, thiab yog tsim los ntawm kev sib cuam tshuam ntawm DNA thiab cov keeb keeb keeb. Ntawm no, ib tug histone octamer yog tsim los ntawm keeb kwm H2A, H2B, H3 thiab H4, txawm hais tias qee qhov lwm qhov kev hloov pauv keeb kwm kuj tseem tuaj yeem pom hauv cov tub ntxhais (piv txwv li, H2A.

Ua kom pom qhov no, lub tswv yim nucleosome yog dab tsi?

A cov nucleosome yog ib feem ntawm DNA uas tau qhwv ib ncig ntawm cov tub ntxhais cov protein. Sab hauv lub nucleus, DNA tsim cov txheej txheem nrog cov protein hu ua chromatin, uas tso cai rau DNA muab cov khoom tso rau hauv qhov me me. Thaum cov chromatin txuas ntxiv thiab saib nyob rau hauv lub tshuab tsom, cov qauv zoo li cov hlaws dai ntawm ib txoj hlua.

Dab tsi yog qhov ua haujlwm ntawm histone?

Lawv lub luag haujlwm yog txhawm rau ntim DNA rau hauv cov txheej txheem hu ua nucleosomes. Histones yog qhov tseem ceeb cov proteins hauv chromatin. Chromatin yog kev sib xyaw ntawm DNA thiab protein ntau uas ua cov ntsiab lus ntawm a ntawm tes nucleus. Vim DNA qhwv ib ncig ntawm histones, lawv kuj ua lub luag haujlwm hauv cov noob kev cai.

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