Kodi kuthetsedwa ndi Rho helicase?
Kodi kuthetsedwa ndi Rho helicase?
Anonim

Pali mitundu iwiri ya transcriptional kuthetsa mu prokaryotes, uwu-odalira kuthetsa ndi intrinsic kuthetsa (amatchedwanso Rho-wodziyimira pawokha kuthetsa). A Rho factor imagwira ntchito pa gawo la RNA. Rho ndi ntchito yofunika ndi yake helicase ntchito, yomwe mphamvu imaperekedwa ndi RNA-amadalira ATP hydrolysis.

Komanso kudziwa ndikuti, kuthetsedwa kodalira rho ndi chiyani?

Intrinsic (kapena uwu-wodziimira) kuthetsa ndipamene RNA imapanga mawonekedwe a hairpin omwe amachotsa RNA Polymerase ndikusiya kusindikiza. Rho-kuthetsedwa kodalira zimachitika pamene uwu mapuloteni amalekanitsa RNA Polymerase ndikuyichotsa pa template.

Kachiwiri, kodi ma eukaryotes ali ndi kutha kodalira rho? Eukaryotes mawonekedwe ndi zovuta zoyambira ndi zinthu zosiyanasiyana zolembera zomwe zimasiyana pambuyo pomaliza. Eukaryotes ali MRNAs omwe ali monocystronic. Kuthetsa mu prokaryotes zimachitika ndi kaya uwu-wodalira kapena uwu-njira zodziyimira pawokha.

Momwemonso, ndi chiyani chomwe chimapereka mphamvu kuti athetse kudalira kwa Rho?

Rho-kuthetsedwa kodalira zimachitika pomanga Rho ku mRNA wopanda ribosome, masamba a C-rich kukhala oyenerera kumangiriza. Rho ndi ATPase imayendetsedwa ndi Rho-mRNA kumanga, ndi amapereka mphamvu kwa Rho kusuntha kwa mRNA; translocation imafuna kutsetsereka kwa uthenga kulowa pakati pa hexamer.

Nchiyani chimayambitsa kuthetsedwa kwa kumasulira?

Kuthetsa imayamba pomwe chizindikiro cha polyadenylation chikuwoneka muzolemba za RNA. Uku ndi kutsatizana kwa ma nucleotides omwe amawonetsa pomwe zolemba za RNA ziyenera kutha. Chizindikiro cha polyadenylation chimadziwika ndi puloteni yomwe imadula zolemba za RNA pafupi, ndikuzitulutsa ku RNA polymerase.

Yotchuka ndi mutu