Bioinformatics Design of the CRISPR/Cas9P300 System for the Purpose of Creating Epigenetic Changes on the Aryl Hydrocarbon Receptor (AHR) Transcription Factor Gene

Background and Aim: AhR(aryl hydrocarbon receptor) is one of thecellular transcription factors that is inactive in many somatic cells. Thechemicals used to activate this transcription factor are largely nonspecific.One of the new and practical methods for activating specificgenes is the use of the CRISPR/dCas9 system. Scientists add specificcomponents specifically designed for this system to produce epigeneticchanges for specific regions that confer epigenetic modifications, and byactivating and deactivating genes.Methods: The AhR promoter region was studied and the areas that havebeen acetylated were identified with use of UCSC browser software. Thenusing CRISPR, CHOPCHOP, and E-CRISP software, sgRNA especiallywas designed for areas close to the sites of the acetylated. In the nextstep, the measurements were needed to have the lowest off-target andthe maximum efficiency. In addition, the CRISPR/Cas9P300 system withmaximum efficiency was used to target an area of interest on acetylatedDNA and to activate the gene.Results: One of the newest systems used to create epigenetic changesfor gene expression changes is CRISPR/Cas9P300. In this study, newdesigning of the system proposed to create targeted epigenetic changeson the Ahr gene. With designed sgRNAs that showed maximum efficiencyand minimum off-target to create a specific deacetylation on the AhRgene, expression of the gene increased thousands of folds. Designingthis system is the most important part of creating changes in the Ahrgene. Designing highly efficient sgRNAs with a very low off-target, fullyspecific for sites that are acetylated is important in deacetylation andgene-specific activation. For best function, this design must be analyzedby several software. In this study, CRISPR, E-CRISP, and CHOPCHOPsoftware were used, and with this highly specialized design, the goal hasbeen achieved.Conclusion: The P300 with acetylation, control of transcription machine,and acting as an adapter molecule, acts on target locations. With theprecise design of the sgRNAs for the closest locations to the acetylatedarea, the CRISPR/dCas9P300 system with a high efficiency leads toprecise activation of the gene. The most important advantage of thisdesign system is the precision and high specificity of the target area,which can indicate the specific function of the system.

Keywords:

Epigenetic , CRISPR/Cas9P300 , Acetylation , sgRNA , Aryl hydrocarbon receptor