رضا معصومی جهاندیزی

Abstract: Interferons are a group of signaling glycoproteins that belong to a large group of cytokines and are a group of proteins that are released from virus-infected host cells and stimulate the immune system and increase the body's resistance. The use of recombinant interferon a2b as a protein therapy in several types of cancer has also been described. Examination of gene expression in melanoma, fibrosarcoma, embryonic fibroblasts and human dendritic cell lines shows that hIFN𝛼 regulates the signal transduction pathway of more than 300 genes in cells. Interferon a2b is now used as a successful treatment. Most of the recombinant proteins are produced in E.coli, it has many advantages in the production of heterologous recombinant proteins and is a good choice due to its ability to grow rapidly. The inability of proteins to fold rapidly to form natural structures turns them into insoluble substances called inclusion bodies or inactive proteins.One approach to solve this problem is to transfer heterologous proteins to the periplasmic space of bacterial hosts using a suitable signal peptides at the N-terminal end of the protein. Expression in the periplasmic space creates an excellent space for proper bonding and twisting. Protein impurities and protease activity in the periplasm are less than in the cytoplasm. It also provides more stability for the expression of heterologous proteins with appropriate folding. This study is based on structural understanding and finding the appropriate signal peptide for the secretory expression of interferon a2b in E.coli. In general, the aim of this study was to find the appropriate signal peptide for the secretory expression of interferon a2b in E.coli. For this purpose, the amino acid sequence of 61 signal peptides was obtained using bioinformatics software and then their physicochemical properties and intracellular location were predicted by In silico methods and inappropriate signal peptides were removed. The selected signal p