Thaum eukaryotes qhwv lawv DNA nyob ib ncig ntawm cov proteins hu ua histones los pab ntim cov DNA rau hauv qhov chaw me, feem ntau cov prokaryotes tsis muaj histones (nrog rau kev zam ntawm cov tsiaj hauv lub npe Archaea). Yog li, ib txoj hauv kev prokaryotes compress lawv DNA mus rau hauv qhov chaw me me yog los ntawm supercoiling supercoiling DNA supercoiling yog hais txog dhau- lossis qis qis ntawm DNA strand, thiab yog ib qho kev qhia ntawm cov kab mob ntawm qhov ntawd. txoj hlua. … Tsis tas li ntawd, qee cov enzymes xws li topoisomerases muaj peev xwm hloov DNA topology los pab txhawb kev ua haujlwm xws li DNA replication lossis transcription. https://en.wikipedia.org › wiki › DNA_supercoil
DNA supercoil - Wikipedia
(Daim duab 1).
Vim li cas histone proteins tsis tuaj hauv prokaryotes?
Vim tias cov proteins histone tsis nyob hauv prokaryotes, muaj qhov tsis muaj tseeb chromosomes Vim tias prokaryotes xws li cov kab mob muaj cov DNA ncig tsis yog chromosomes. Lub xub ntiag ntawm cov chromosomes tseeb tuaj yeem pom hauv cov hlwb eukaryotic xws li cov nroj tsuag thiab tsiaj hlwb.
Puas muaj histones nyob hauv eukaryotes?
Histones yog ib tsev neeg ntawm cov proteins yooj yim uas koom nrog DNA hauv lub nucleus thiab pab ua kom nws mus rau hauv chromatin, lawv yog cov alkaline (pH) cov proteins, thiab lawv cov nqi zoo tso cai rau lawv koom nrog DNA. Lawv yog pom nyob rau hauv lub nucleus ntawm eukaryotic hlwb
Puas muaj histones nyob rau hauv cov kab mob?
Histones. DNA tau qhwv ib ncig ntawm cov proteins no los tsim ib qho kev hu ua chromatin thiab tso cai rau DNA tau ntim thiab ntim rau hauv qhov chaw me me thiab me dua. Hauv yuav luag txhua eukaryotes, histone-based chromatin yog tus qauv, tseem hauv cov kab mob, tsis muaj histones.
Puas histones tsis nyob hauv cov kab mob?
Bacteria tsis muaj histone proteins thiab. Los ntawm cov ntaub ntawv saum toj no peb tau pom tias lub cev golgi thiab histone proteins tsis nyob hauv cov kab mob. Li no, lo lus teb raug yog kev xaiv (B).
