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Kislotai ribonukleinat – KRN.

Kislotai ribonukleinat monandi KDN polimer buda, monomerhoi on nukleotidhoyand. Asoshoi nitrogenii se nukleotid niz monandi nukleo tidhoi tarkibi KDN (adenin, guanin, sitozin) meboshand:

asosi nitrogenii chahorum dar KRN ba joi timin uratsil ishtirok menamoyad. Nukleotidhoi KRN az nukleotidhoi KDN bo sokhti angishtobhoi tarkibashon niz farq mekunand; onho dar khud pentozai digar – ba joi dezoksiriboza-riboza dorand. Dar zanjiri KRN nukleotidho bo rohi ba vujud omadani bandho bayni ribozai yak nukleotid va boqimondai kislotai fosfati nukleotidi digar payvast meshavand.

3-10

KRN akhborro oid ba paydarhamii aminokislotaho dar safedaho, yane oid ba strukturai safedaho, az khromosoma ba mavzei sintezi onho guzaronida, dar hosilshavii safedaho ishtirok menamoyad. Az rui struktura KRN-a dusilsi-

la (duzanjira) va yaksilsila (yakzanjira) meshavad. KRN-a dusilsila dar baze virusho hamchun nigohdorandai akhbori genetiki khizmat menamoyad (nigared ba bobi 5), yane dar onho funksiyai khromosomaro ijro menamoyad.

CHand navi KRN-a yaksilsila mavjudand. Onho az rui funksiya yo mavqei khud dar hujayra nom giriftaand. Qismi ziyodi sitoplazmaro (to 80-90%) KRN-i ribosomi (KRN-r), ki dar ribosomaho mavjud ast, tashkil menamoyad. Moleku-

lai KRN-r kalon nest va taqriban az 3-5 hazor nukleotidho iborat meboshad. Kislotahoi ribonukleinat az darozii  qismi kislotahoi dezoksiribonukleinat, ki dar hamon qism onho sintez meshavand, vobastagi dorand. Molekulai KRN-a metavonad az 3000–30000 nukleotidho iborat boshad.

KRN–i naqliyoti (KRN-n) 76–85 nukleotid- horo dokhil karda, yakchand funksiyaro ijro menamoyad (rasmi 3.10). On aminokislotahoro ba joi (nuqtai) sintezi safeda rasonda, mavqei aniqi aminokislotahoro dar ribosoma muayyan mekunad.

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