A Study on microRNAs Targeting the Genes Overexpressed in Lung Cancer and their Codon Usage Patterns.

As reported by WHO in 2018, there were 2.09 million victims of lung cancer and 1.76 million fatalities worldwide. Tobacco remains the biggest hazard in causing this lethal disease. To execute the computational analysis, the overexpressed lung cancer genes were retrieved from literature and subsequently their complete coding sequences (CDS) were downloaded. The mature microRNA sequences of human were extracted from miRBASE. The 7mer-m8 perfect seed match between miRNAs and mRNAs was found. Following filtration, 7 genes were selected that possessed binding sites for maximum miRNAs viz., MUC5B (miR-4479, miR-1227-5p, miR-3940-5p, miR-604, miR-4455, miR-4267, miR-6750-3p, miR-4530, miR-5587-5p, miR-4508, miR-4534, miR-4443, miR-4253, miR-1321, miR-4655-5p, miR-4297, miR-4296, miR-1268a, miR-3178, miR-4750-3p, miR-1306-3p, miR-1268b, miR-3656, miR-1233-3p, miR-6804-5p), MUC16 (miR-4456, miR-1205, miR-665, miR-6808-3p, miR-1279, miR-4257, miR-1227-5p, miR-888-3p, miR-4455, miR-4267, miR-4294, miR-1275, miR-4288, miR-1178-5p, miR-4314, miR-6829-3p, miR-548av-5p, miR-1294, miR-5587-5p, miR-3622b-5p, miR-1273f, miR-4770, miR-4327, miR-4318, miR-4531, miR-4534, miR-4443, miR-7106-5p, miR-3125, miR-3650, miR-4325, miR-4266, miR-7976, miR-1290, miR-4500, miR-7160-5p, miR-4291, miR-1306-3p, miR-6130, miR-4430, miR-4725-5p, miR-4441, miR-6077, miR-1304-5p, miR-7515, miR-3182, miR-6134), COL1A1 (miR-3665, miR-1227-5p, miR-6132, miR-2861, miR-4530, miR-3155b, miR-3155a, miR-1292-3p, miR-4497), COL5A1 (miR-7162-5p, miR-3665, miR-6809-3p, miR-4313, miR-4531, miR-4532, miR-3155b, miR-4323, miR-1207-3p, miR-4260, miR-6071, miR-4710, miR-7162-5p), CELSR2 (miR-7150, miR-4308, miR-6132, miR-4770, miR-4534, miR-4492, miR-3960, miR-3178, miR-4291, miR-563), COL7A1 (miR-665, miR-6730-3p, miR-1227-5p, miR-4265, miR-6829-3p, miR-4297, miR-4532, miR-3181, miR-4310, miR-4441, miR-4497, miR-1237-3p), and FAT2 (miR-4267, miR-1275, miR-4770, miR-1825, miR-6895-5p, miR-4535, miR-4493, miR-940, miR-6861-3p, miR-4310, miR-4710, miR-4447, miR-4472). The miRNA-target site and their flank regions were compared with respect to site accessibility, translational rate, and relationship between RSCU and tRNAs. Higher accessibilities to miRNA-binding regions and lower translational rates indicated that miRNAs' binding to their respective targets might be efficient. The presence of rare codons might further augment miRNA targeting. The codon usage bias study of the genes related to lung cancer revealed non-uniform usage of nucleotides and comparatively higher GC content. Lower biasness prevailed in the genes and selective constraint mostly governed them. Lastly, the functionalities of target genes were also revealed. The silencing characteristic of miRNAs might be exploited to design miRNA-mediated therapy that might potentially repress the overexpressed genes in carcinoma.

Identification of promising CD8 and CD4 T cell epitopes for peptide vaccine formulation against SARS-CoV-2.

The novel virus "severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)" has been responsible for the worldwide pandemic causing huge devastation and deaths since December 2019. The disease caused by this virus is known as COVID-19. The present study is based on immuno-informatics approach to develop a multi-epitope-loaded peptide vaccine to combat the COVID-19 menace. Here, we have reported the 9-mer CD8 T cell epitopes and 15-mer CD4 T cell epitopes, free from glycosylation sites, belonging to three proteins, viz. surface glycoprotein, membrane glycoprotein and envelope protein of this virus. Immunogenicity, aliphatic amino acid, antigenicity and hydrophilicity scores of the predicted epitopes were estimated. In addition, other physicochemical parameters, namely net charge, Boman index and amino acid contents, were also accounted. Out of all the epitopes, three CD8 T cell epitopes viz. PDPSKPSKR, DPSKPSKRS and QTQTNSPRR and three CD4 T cell epitopes viz. ASYQTQTNSPRRARS, RIGNYKLNTDHSSSS and RYRIGNYKLNTDHSS were found to be efficient targets for raising immunity in human against this virus. With the help of our identified potent epitopes, various pharma industries might initiate efforts to incorporate those epitopes with carrier protein or adjuvant to develop a multi-epitope-loaded peptide vaccine against SARS-CoV-2. The peptide vaccines are usually cost-effective and therefore, could be administered as a preventive measure to combat the spread of this disease. Proper clinical trials must be conducted prior to the use of identified epitopes as vaccine candidates.

Binding sites of miRNA on the overexpressed genes of oral cancer using 7mer-seed match.

The microRNAs having a length of ~ 19-22 nucleotides are the small, non-coding RNAs. The evolution of microRNAs in many disorders may hold the key to tackle complex challenges. Oral cancer belongs to the group of head and neck cancer. It occurs in the mouth region that appears as an ulcer. In this study, we collected information on the overexpressed genes of oral cancer. The coding sequences of the genes were derived from NCBI and the entire set of human microRNAs present in miRBASE 21 was retrieved. The human microRNAs that can target the overexpressed genes of oral cancer were determined with the aid of our in-house software. The interaction between microRNAs and the overexpressed genes was evaluated with 7mer-m8 model of microRNA targeting. The genes DKK1 and APLN paired with only one miRNA i.e., miR-447 and miR-6087, respectively. But the genes INHBA and MMP1 were found to be targeted by 2 miRNAs, while the genes FN1, FAP, TGFPI, COL4A1, COL4A2, and LOXL2 were found to be targeted by 16, 5, 9, 18, 29, and 11 miRNAs. Subsequently, several measures such as free energy, translation efficiency, and cosine similarity metric were used to estimate the binding process. It was found that the target region's stability was higher than the upstream and downstream zones. The overexpressed genes' GC contents were calculated, revealing that the codons in target miRNA region were overall GC rich as well as GC3 rich. Lastly, gene ontology was performed to better understand each gene's involvement in biological processes, molecular function, and cellular component. Our study showed the role of microRNAs in gene repression, which could possibly aid in the prognosis and diagnosis of oral cancer.

Identification of putative microRNAs in the complete genome of Mycobacterium avium and their possible interaction with human transcripts.

The grievous adversity regarding Mycobacterium avium is its ubiquitous nature. Isolation of the bacteria from drinking water, house dust, and soil, etc., is an alarming issue for the scientific community. The microRNAs are the molecular influencers of gene expression that act during the process of post transcription. A few reports claimed the existence of microRNAs or microRNA-like molecules in the prokaryotic species. Biogenesis of bacterial miRNAs requires their transport into the host cell. Subsequently, the host-encoded enzymes are exerted for the formation of bacterial mature miRNAs and their regulation. In our study, the screening of complete genome of Mycobacterium avium revealed six putative precursor microRNA sequences bearing typical secondary structures. The mature microRNAs were predicted in both arms of the secondary structures. A total of 12 possible mature microRNAs were identified in this study. The likely targets of the predicted mature miRNAs were searched in human 3' UTR. In the human transcriptome, 193 genes were possibly targeted by 12 mature miRNAs of Mycobacterium avium. The essential functionalities of the target genes included signal transduction, immune system, DNA binding, and response to stress.

Compositional features and pattern of codon usage for mitochondrial CO genes among reptiles.

The phenomenon of non-random occurrence of synonymous nucleotide triplets (codons) in the coding sequences of genes is the codon usage bias (CUB). In this study, we used bioinformatic tool kit to analyze the compositional pattern and CUB of mitogenes namely COI, COII and COIII across different orders of reptiles. Estimation of overall base composition in the protein-coding sequences of COI, COII and COIII genes of the reptilian orders revealed an uneven usage of nucleotides. The overall count of A nucleotide was found to be the highest while the overall count of G nucleotide was the least. The CO genes across the three reptilian orders were prominently AT biased. Comparison of the GC proportion at each codon position displayed that GC1 percentage ranked the highest in all the three CO genes of the reptilian orders. SCUO values indicated weaker CUB, while considerable variation of SCUO values existed in the three CO genes across the studied reptiles. Relative synonymous codon usage (RSCU) values indicated that mostly the A ending codons were preferred. Based on the parameters namely neutrality plot, mutational responsive index and translational selection, we could conclude that natural selection was the major evolutionary force in COI, COII and COIII genes in the studied reptilian orders. However, correspondence analysis, parity plot and correlation studies indicated the existence of mutation pressure as well on the CO genes.

Silencing lung cancer genes using miRNAs identified by 7mer-seed matching.

Lung cancer (LC) is the main cause of cancer-associated deaths in both men and women globally with a very high mortality rate. The microRNAs (miRNAs) are a class of noncoding RNAs consisting of 18-25 nucleotides. They inhibit translation of protein through binding to complementary target mRNAs. The non-coding miRNAs are recognized as potent biomarkers for detection, development and treatment of malignancy. In this study, we screened a set of 12 genes over expressed in small cell lung cancer, non small cell lung cancer and the genes involved in both categories and their binding sites for human miRNAs as no work was reported yet. Screening of human miRNAs revealed that a few genes showed numerous miRNA binding sites. Free energy values of mRNA sequences revealed that they might acquire compact folded structure causing complexity for miRNAs to interact. GC content in the target site was relatively higher than that of their flanks. It was observed through analysis of cosine similarity metric and compAI parameters that the genes related to lung cancer were encoded with non optimal codons and thus might be translationally less efficient for producing polypeptides. Gene ontology analysis was carried out to understand the diverse functions of these 12 genes.

Drug resistant Tuberculosis: A review.

Tuberculosis (TB) was announced as a global emergency in 1993. There was an alarming counter attack of TB worldwide. However, when it was known that TB can be cured completely, the general public became ignorant towards the infection. The pathogenic organism Mycobacterium tuberculosis continuously evolved to resist the antagonist drugs. This has led to the outbreak of resistant strain that gave rise to "Multi Drug Resistant-Tuberculosis" and "Extensively Drug Resistant Tuberculosis" that can still be cured with a lower success rate. While the mechanism of resistance proceeds further, it ultimately causes unmanageable totally drug resistant TB (TDR-TB). Studying the molecular mechanisms underlying the resistance to drugs would help us grasp the genetics and pathophysiology of the disease. In this review, we present the molecular mechanisms behind Mycobacterium tolerance to drugs and their approach towards the development of multi-drug resistant, extremely drug resistant and totally drug resistant TB.

A Crosstalk on Codon Usage in Genes Associated with Leukemia.

Leukemia is the outcome of aggregation of damaged white blood cells. Several genes were reported to be associated with the pathogenesis of leukemia. These genes were computationally analyzed to decipher their codon usage bias (CUB) and to identify the prime factors influencing the codon usage profile as no work was reported yet. The mean values of synonymous codon usage order (SCUO) parameter indicated low CUB of the genes. Significant positive association of SCUO with overall GC and positional GCs might signal the presence of mutational pressure. However, neutrality plot suggested the dominant role of natural selection across the genes. Along with natural selection, the role of mutation pressure was also prominent and that might be responsible for lower CUB (SCUO = 0.19) of genes. Low translational speed might permit accuracy in the process. A strong inverse relationship of translational rate was observed with CUB of genes and folding energy.

Synonymous codon usage and context analysis of genes associated with pancreatic cancer.

Pancreatic cancer is a fatal disorder which originates in pancreas. Its mortality rate is increasing with time. Some studies also reported that pancreatic cancer would be ranked 2nd by the year 2030. Codon usage bias (CUB) arises when synonymous codons for each amino acid are not used randomly in the coding sequences of genes. We used bioinformatic methods to analyze the compositional properties, codon context and codon usage trend of the genes associated with pancreatic cancer as no work was reported yet. From the base composition analysis, the pancreatic cancer genes were found to be GC-rich and at the 3rd codon position the G/C ending codons were more preferred to A/T ending ones. The CUB was low in genes associated with pancreatic cancer. Correspondence analysis proposed that other than base constraints, CUB might also be affected by some other factors such as natural selection. Moreover, results of correlation analysis indicated that CUB and various GC contents i.e. GC, GC1, GC2, GC3 played important role in the release of free energy by transcripts of the genes associated with pancreatic cancer. The low compAI values of coding sequences suggested a low translation rate of the genes.

Chronic obstructive pulmonary disease: A crosstalk on nucleotide compositional dynamics and codon usage patterns of the genes involved in disease.

Chronic obstructive pulmonary disease (COPD), a lung disease, affects a large number of people worldwide, leading to death. Here, we analyzed the compositional features and trends of codon usage of the genes influencing COPD to understand molecular biology, genetics, and evolutionary relationships of these genes as no work was reported yet. Coding sequences of COPD genes were found to be rich in guanine-cytosine (GC) content. A high value (34-60) of the effective number of codons of the genes indicated low codon usage bias (CUB). Correspondence analysis suggested that the COPD genes were distinct in their codon usage patterns. Relative synonymous codon usage values of codons differed between the more preferred codons and the less-preferred ones. Correlation analysis between overall nucleotides and those at third codon position revealed that mutation pressure might influence the CUB of the genes. The high correlation between GC12 and GC3 signified that directional mutation pressure might have operated at all the three codon positions in COPD genes.

DNA compositional dynamics and codon usage patterns of M1 and M2 matrix protein genes in influenza A virus.

Influenza A virus subtype H3N2 has been a serious health issue across the globe with approximately 36 thousand annual casualties in the United States of America only. Co-circulation in avian, swine and human hosts has led to frequent mutations in the virus genome, due to which development of successful antivirals against the virus has become a formidable challenge. Recently, focussed research is being carried out targeting the matrix proteins of this strain as vaccine candidates. This study is carried out to unravel the key features of the genes encoding the matrix proteins that manoeuvre the codon usage profile in the H3N2 strains. The findings reveal differential codon choice for both matrix protein 1 and matrix protein 2. The overall codon usage bias is less pronounced in both the datasets which is evident from higher value of effective number of codons (>55). Comparison of the codon usage for both the genes under study with that of humans revealed that the viral codon usage is not fully optimized for the human host conditions. Both the genes enrolled in the study showed variation which was reflected in almost all the indices used for codon usage studies. Neutrality analysis revealed a weak role of mutation pressure while selection was the major contributor towards codon usage.