Background: Prokaryotic systems such as E. coli are among the most affordable and simplest hosts which are being employed to express recombinant proteins, nevertheless without appropriate signal peptide these systems cannot be used for secretory proteins. Bovine pancreatic ribonuclease A is a protein with four disulfide bonds which might be used as an immunoenzyme for immunotherapy. Consequently, the production of this recombinant protein, using prokaryotic system, requires a suitable signal peptide to protect disulfide bonds and to prevent misfolding. Objective: This study was designed to predict the best signal peptides to express bovine pancreatic ribonuclease A protein in E. coli. Methods: In this study, 42 signal sequences were selected from data bases and the most important features of them were evaluated. First, n, h and c regions of signal peptides and their probability were investigated by signalP software’s version 3 and 4.1. Then, physico–chemical features of them were evaluated by Portparam and SOLpro. Also, secretion sorting and sub-cellular localization sites were evaluated by PRED-TAT and ProtcompB software programs. Results: The results showed that among all studied signal peptides only 28 out of 41 remained signal peptides could be considered as appropriate secretory signal peptides. Conclusion: Finally, Phage shock protein E, ranked as the best signal peptide and after that, pectate lyase B, F41 fimbrial protein and Lipopolysaccharide export system protein lptA considered as next best signal peptides which were approved by in silico tools as the most appropriate secretory signal peptides in E. coli. However, further experiments are required to validate these in silico results.

Introduction: Gastric cancer is one of the most common cancers in the world. This study aimed to identify genes, biomarkers, and metabolic pathways affecting gastric cancer using bioinformatic analysis and meta-analysis. Methods: Datasets containing gene expression profiles of tumor lesions and adjacent non-tumor mucosa samples were downloaded. Common differentially expressed genes between data sets were selected to identify hub genes and further analysis. Gene Expression Profiling and Interactive Analyses (GEPIA) and the Kaplan-Meier method were used to further validate the expression level of genes and plot the overall survivalcurve, respectively.Results and disscussion: KEGG pathway analysis showed that the most important pathway was enriched in ECM-receptor interaction. Hub genes includingCOL1A2, FN1, BGN, THBS2, COL5A2, COL6A3, SPARC and COL12A1 wereidentified. The top interactive miRNAs including miR-29a-3p, miR-101-3p,miR-183-5p, and miR-15a-5p targeted the most hub genes. The survival chart showed an increase in mortality in patients with gastric cancer, which shows the importance of the role of these genes in the development of the disease and can be considered candidate genes in the prevention and early diagnosis of gastric cancer.

Feed efficiency is important due to the high cost of food, which accounts for about 70% of the total cost of a turkey breeding system. Native poultry are an important genetic resource in poultry breeding programs. This study aimed to conduct a global transcriptome analysis of native male turkeys which have been phenotyped for high and low feed efficiency. Feed efficiency traits were recorded during the experimental period. After slaughter, the three most efficient and three least efficient male turkeys were selected for RNA-Seq analysis. A total of 365 genes with different expressions in muscle tissue were identified between turkeys with a high feed efficiency compared to turkeys with a low feed efficiency. In the pathway analysis of up-regulated genes, major pathways included the “metabolism of glycine, serine, and threonine”; the “adipocytokine signaling pathway” and the “biosynthesis of amino acids”. In the pathway analysis of down-regulated genes, the major pathways included “dorso-ventral axis formation” and “actin cytoskeleton regulation”. In addition, gene set enrichment analyses were performed, which showed that high feed efficiency birds exhibit an increased expression of genes related to the biosynthesis of amino acids and low feed efficiency birds an increased expression of genes related to the immune response. Furthermore, functional analysis and protein network interaction analysis revealed that genes including GATM, PSAT1, PSPH, PHGDH, VCAM1, CD44, KRAS, SRC, CAV3, NEDD9, and PTPRQ were key genes for feed efficiency. These key genes may be good potential candidates for biomarkers of feed efficiency in genetic selection in turkeys.