Design and identification of miRNA with a server RNAhybride for different transcripts of Ras gene in colorectal cancer

Introduction Colorectal cancer is the second and third most common adult cancer in women and men, so it is the fourth cause of death in the world. The survival rate of this disease is ۵ and ۱۰ years in ۶۵% and ۵۸% of patients, respectively, and the prevalence of death in men is ۲۵% higher than in women. Factors related to colorectal cancer include obesity, lifestyle, unhealthy diet, smoking, and alcohol consumption. Gene Ras is located in ۱۲p۱۲.۱ has ۷ exons and ۶ transcript , and has ۴ isoforms, k-ras, N-ras, H-ras, and ۵ isoforms, which are the most similar to each other, and has G domains(۱-۱۶۶aa), and the C-terminal(۱۶۶-۱۸۹aa) region has diversity, different mutation rates for gene Ras in different cancers. For example, the highest mutation rate for this cancer is related to pancreatic cancer (۶۶%) and colorectal cancer (۳۴%) and lung cancer (۱۶%). MicroRNAs are small, non-coding RNA molecules that suppress gene expression both by inhibiting protein translation and promoting mRNA cleavage and they are between ۱۹-۲۵ nucleotides long.In this article, the aim is to design and identify the best and most complementary miRNA for different gene Ras transcripts, which were identified and designed with bioinformatics tools and different servers. Materials and methods Step۱ : Using server KEGG for signaling pathways in colorectal cancer pathogenesis and determining miRNA which have increased or decreased expression in this cancer and its relationship with different genes. Step ۲ : In this step, server miRDB was used to determine the list of miRNA complements with gene Ras, and ۳ of those with the highest scores were selected. Step ۳: In this stage, server miRBase shows the desired ۵ miRNA sequence. Step ۴: In this stage, the sequence of different transcripts of genes Ras and miRNA was downloaded from site NCBI. Step۵: At this stage, Server RNAhybrid was used for molecular interaction between miRNAs and different transcripts of the Ras gene. results In the interaction results section, ۵ Ras gene transcripts are displayed with ۵miRNA, and as a result, the amount of free energy is indicated by mfe, and this means that the more negative this value is, the more stable this interaction is, and in addition to this parameter, the number The connecting nucleotides between the ۳- Ras gene region and the ۵-miRNA region also play an important role in the stability of the connection. Discusion and conclusion Determining the list of miRNA complements was used with gene Ras, and ۵ of them that had the highest score were selected, then these miRNA were placed in server RNA hybrid, and as a result, miR-let-۷c-۵p(۵-UUCAUGAACUGGGUCUAGCUUGG-۳) had the most desire and stability of energy with ۵ different transcript of Ras gene because it had the most free energy. and on the other hand, the number of terminal nucleotides ۳-mRNA and ۵-miRNA also determines this stability, and the highest binding number of nucleotides was related to miR-let-۷c-۵p, which the number of binding nucleotides is ۱۱ nucleotides .

کلیدواژه ها:

Clorectal cancer ، miRNA ، RAS Gene ، bioinformatic tools