Tobankii sano ee la soo dhaafay, tignoolajiyada tafatirka hidda-wadaha ee ku saleysan CRISPR ayaa si degdeg ah u horumaray, waxaana si guul leh loogu dabaqay daawaynta cudurrada hidaha iyo kansarka ee tijaabooyinka bukaan-socodka ee bini-aadmiga.Isla mar ahaantaana, saynisyahannada adduunka oo dhan waxay si joogto ah u taabtaan qalab cusub oo leh karti tafatirka hidda-wadaha si ay u xalliyaan dhibaatooyinka aaladaha tafatirka hidda-wadaha ee jira iyo go'aannada.

Bishii Sebtembar 2021, kooxda Zhang Feng waxay daabacday warqad joornaalka Sayniska [1], waxayna ogaadeen in tiro badan oo transposters ah oo sumadeeyay RNA ay hagto enzymes nucleic acid waxayna u bixiyeen nidaamka Omega (oo ay ku jiraan ISCB, ISRB, TNP8).Daraasadu waxay sidoo kale ogaatay in nidaamka Omega uu isticmaalo qayb ka mid ah RNA si uu u hago jarista silsiladaha DNA-da ee laba geesoodka ah, kuwaas oo ah ωRNA.Waxaa ka sii muhiimsan, enzymes nucleic acid waa kuwo aad u yar, kaliya qiyaastii 30% CAS9, taas oo macnaheedu yahay in ay u badan tahay in la geeyo unugyada.

Oktoobar 12, 2022, kooxda Zhang Feng ayaa lagu daabacay joornaalka Dabiiciga ah ee ciwaankiisu yahay: Qaab dhismeedka Omega Nickase ISRB ee Complex oo leh ωrna iyo Target DNA [2].

Daraasadu waxay si dheeraad ah u lafagurtay qaab dhismeedka mikroskoob ee elektarooniga ah ee la qaboojiyey ee ISRB-ωRNA iyo bar-tilmaameedka DNA-ga ee nidaamka Omega.

ISCB waa awoowga CAS9, ISRB-na waa shay la mid ah la'aanta HNH nucleic acid domain ISCB, markaa cabbirku wuu ka yar yahay, kaliya qiyaastii 350 amino acids.DNA sidoo kale waxay bixisaa aasaaska horumarinta dheeraadka ah iyo isbeddelka injineernimada.

IsrB-ta ay hagto RNA waa xubin ka tirsan qoyska OMEGA oo ay dejisay IS200/IS605 superfamily of transposons.Laga soo bilaabo falanqaynta phylogenetic iyo qaybaha gaarka ah ee la wadaago, IsrB waxay u badan tahay inay noqoto horudhaca IscB, kaas oo ah awoowaha Cas9.

Bishii Maajo 2022, Jaamacadda Cornell's Lovely Dragon Laboratory ayaa ku daabacday warqad joornaalka Sayniska [3], oo lagu falanqeynayo qaab dhismeedka IscB-ωRNA iyo habka loo gooyo DNA.

Marka la barbardhigo IscB iyo Cas9, IsrB waxay ka maqan tahay HNH nuclease domain, REC lobe, iyo inta badan PAM-ka isdhexgalka ee isku xigxiga, sidaas darteed IsrB aad ayuu uga yar yahay Cas9 (kaliya qiyaastii 350 amino acids).Si kastaba ha noqotee, cabbirka yar ee IsrB waxaa isku dheeli tiran hage RNA oo aad u weyn (omega RNA wuxuu ku saabsan yahay 300 nt dheer).

Kooxda Zhang Feng waxay falanqeeyeen qaab dhismeedka microscope cryo-electron ee IsrB (DtIsrB) ee bakteeriyada anaerobic-ka qoyan ee Desulfovirgula thermocuniculi iyo kakan ωRNA iyo bartilmaameedka DNA.Falanqaynta qaabdhismeedku waxay muujisay in qaabka guud ee borotiinka IsrB uu la wadaago qaab-dhismeedka laf dhabarta borotiinka Cas9.

Laakiin farqiga u dhexeeya ayaa ah in Cas9 ay isticmaasho REC lobe si ay u fududayso aqoonsiga bartilmaameedka, halka IsrB ay ku tiirsan tahay ωRNA, qayb ka mid ah taas oo samaysa qaab dhismeed saddex-geesood ah oo adag oo u dhaqma sida REC.

Si loo fahmo isbeddellada qaabdhismeedka IsrB iyo Cas9 inta lagu guda jiro horumarka ka yimid RuvC, kooxda Zhang Feng waxay barbardhigeen qaab-dhismeedka DNA-da ee bartilmaameedka ah ee RuvC (TtRuvC), IsrB, CjCas9 iyo SpCas9 ee Thermus thermophilus.

Falanqaynta qaabdhismeedka IsrB iyo ωRNA waxay caddaynaysaa sida IsrB-ωRNA ay si wadajir ah u aqoonsanayaan oo ay u kala gooyaan bartilmaameedka DNA-da, iyo sidoo kale waxay siisaa aasaaska horumarinta dheeraadka ah iyo injineernimada nuklease-yar.Isbarbardhigga nidaamyada kale ee lagu hagayo RNA waxay muujinayaan isdhexgalka shaqeynta ee ka dhexeeya borotiinnada iyo RNA-yada, horumarinta fahamkeenna bayoolajiga iyo horumarka nidaamyadan kala duwan.

Xiriirinta:

1.https://www.science.org/doi/10.1126/science.abj6856

2.https://www.science.org/doi/10.1126/science.abq7220

3.https://www.nature.com/articles/s41586-022-05324-6