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Coronavirus belongs to the coronaviridae family, having a single-stranded RNA as genetic material of 26–42 kb in size. The first coronavirus infection emerged in 2002, caused by SARS-CoV1. Since then, genome sequences and three-dimensional structures of crucial proteins and enzymes of the virus have been studied in detail. The novel coronavirus (nCoV) outbreak has caused the COVID19 pandemic, which is responsible for the deaths of millions of people worldwide. The nCoV was later renamed as SARS-CoV2. The details of most of the COV proteins are available at the atomic and molecular levels. The entire genome is made up of 12 open reading frames that code for 27 different proteins. The spike surface glycoprotein, the envelope protein, the nucleocapsid protein, and the membrane protein are the four structural proteins which are required for virus attachment, entrance, assembly, and pathogenicity. The remaining proteins encoded are called non-structural (NSPs) and support the survival of the virus. Several non-structural proteins are also validated targets for drug development against coronavirus and are being used for drug design purposes. To perform a comparative study, sequences and three-dimensional structures of four crucial viral enzymes, Mpro, PLpro, RdRp, and EndoU from SARS-CoV1 and SARS-CoV2 variants were analyzed. The key structural elements and ligands recognizing amino acid residues were found to be similar in enzymes from both strains. The significant sequences and structural resemblance also suggest that a drug developed either for SARS-CoV1 or SARS-CoV2 using these enzymes may also have the potential to cross-react. Communicated by Ramaswamy H. Sarma

Diabetic retinopathy (DR) is a common complication amongst patients that have diabetes. It is a leading cause of blindness in middle age people. A large proportion of patients who have diabetes develop retinopathy. There are several immunological reasons associated with the pathophysiology of this disease. Role of several mediators that increase the oxidative stress and have a pro-inflammatory effect which leads to capillary occlusion and neovascularization (NV). Increased vasopermeability due to disruption of the blood-retinal barrier (BRB) leading to diabetic macular edema (DME). Immunotherapies utilise different compounds and target various inflammatory molecules like TNF-α and pathways such as PPARγ for treatment of this progressive disease. Inflammatory and pro-inflammatory pathways are found to have an essential role in promoting DR; therefore, targeting them provides a useful technique for curing DR.

The novel Coronavirus disease 2019 (COVID-19) is potentially fatal and caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Due to the unavailability of any proven treatment or vaccination, the outbreak of COVID-19 is wreaking havoc worldwide. Hence, there is an urgent need for therapeutics targeting SARS-CoV-2. Since, botanicals are an important resource for several efficacious antiviral agents, natural compounds gaining significant attention for COVID-19 treatment. In the present study, methyltranferase (MTase) of the SARS-CoV-2 is targeted using computational approach. The compounds were identified using molecular docking, virtual screening and molecular dynamics simulation studies. The binding mechanism of each compound was analyzed considering the stability and energetic parameter using in silico methods. We have found four natural antiviral compounds Amentoflavone, Baicalin, Daidzin and Luteoloside as strong inhibitors of methyltranferase of SARS-CoV-2. ADMET prediction and target analysis of the selected compounds showed favorable results. MD simulation was performed for four top-scored molecules to analyze the stability, binding mechanism and energy requirements. MD simulation studies indicated energetically favorable complex formation between MTase and the selected antiviral compounds. Furthermore, the structural effects on these substitutions were analyzed using the principles of each trajectories, which validated the interaction studies. Our analysis suggests that there is a very high probability that these compounds may have a good potential to inhibit Methyltransferase (MTase) of SARS-CoV-2 and to be used in the treatment of COVID-19. Further studies on these natural compounds may offer a quick therapeutic choice to treat COVID-19. Communicated by Ramaswamy H. Sarma

Protein kinases are the family of attractive enzyme targets for drug design with relevance to cancer biology. Serine arginine protein kinase 1 (SRPK1) is responsible for the phosphorylation of serine/arginine (SR)-rich proteins. Alternative Splicing Factor/Splicing Factor 2 (ASF/SF2) involved in mRNA editing. ASF/SF2 is over expressed in many cancers and plays crucial roles in the cell survival. Phosphorylation of ASF/SF2 is decisive for its functions in cancer. In search of potential anticancer therapeutic agents for attenuating phosphorylation of ASF/SF2, we have explored specific and potential inhibitors of SRPK1 from natural and drug like compounds databases using in-silico methods. Compound ZINC02154892 (C02) was found to be the most potent inhibitor for SRPK1. In-vitro molecular and cell biology studies have shown C02 as a potent and specific inhibitor of phosphorylation of ASF/SF2 and cell survival in leukemic cell line. Structural analysis of SRPK1 with compound C02 revealed a unique pattern of binding targeting ATP binding site along with inhibiting recruitment of ASF/SF2 by SRPK1. The possibilities of compound C02 to be used as a lead compound paving way for the development of potent and specific inhibitors of SRPK1 for designing of novel potential anticancer inhibitor is inferred from the current studies.

A novel coronavirus (SARS-COV-2) overflow event, with its epicenter point in the Wuhan (China), has risen as the health of the public crisis is of global concern. This started as an episode in the December, (2019), and till the 28th of February, (2020), there have about 83,704 committed cases of the SARS-COV-2 (COVID-19) disease at the global level, including 2,859 deaths. This showed overall cases including 3.41% of the fatality rate. At this point more than 58 nations or regions were affected with SARS-COV-2 (COVID-19) disease. As an important role of the worldwide response to manage and contain this pandemic, significant accentuation was put to create research knowledge in order to manage proof based response to carry the infection. This disease was named as severe respiratory syndrome COVID-19 (SARS-CoV-2), owing to its hereditary similarities with the SARS infection. Individual to-individual transmission of the COVID-19 contamination led to the isolation of the patients that were treated with various types of treatments. Various measures have been executed to decrease the individual to-individual transmission of the SARS-CoV-2, to stop the present outbreak. Unique considerations and many efforts ought to be applied in the populations to decrease the transmission of COVID-19 including health care providers, kids and older individuals. The aims of this review were to highlight the epidemiology, transmission, diagnosis and future instructions of COVID-19 to stop spreading of this lethal disease.

In this 21st century who isn't enticed by the glamorous and appealing life in the fast lane? We are surrounded by wonders, something we could never have imagined erstwhile. We have everything just a click or a call away. This alluring lifestyle comes with its own perils, the biggest one being concerned with health which is often compromised with check ins and home delivered food but the problem doesn't just lie with the outside food but also with all those chemical enriched engineered expensive food items. The industry often tempers with our food to make it "More Attractive" to the consumer. However, in modern era, availability of drugs and fancy powders has led to imbalance of health and nutrition, contrary to the previous era when home gardening was very common and people preferred fresh-foods which didn't contain added chemicals. They even used to treat some of the health problems with the natural ways that we nowadays refer to DIYs (Do-it-yourselves). Since Ayurveda used natural herbs and plant extracts for treatment, the earth was fresher and less-polluted which led to greater life expectancy. The modern era also has its own benefits like excellences in allopathy medicine has brought a cure to many untreatable diseases of the ancient times, and have even eradicated certain diseases like smallpox and polio. To summarize, both the time had their own pros and cons, so it would be better if we take both of their advantages into consideration and work ahead to live a healthy life.

SARS-CoV-2 is causative agent of COVID-19, which is responsible for severe social and economic disruption globally. Lack of vaccine or antiviral drug with clinical efficacy suggested that drug repurposing approach may provide a quick therapeutic solution to COVID-19. Nonstructural protein-15 (NSP15) encodes for an uridylate-specific endoribonuclease (EndoU) enzyme, essential for virus life cycle and an attractive target for drug development. We have performed in silico based virtual screening of FDA approved compounds targeting EndoU in search of COVID-19 drugs from commercially available approved molecules. Two drugs Glisoxepide and Idarubicin used for treatment for diabetes and leukemia, respectively, were selected as stronger binder of EndoU. Both the drugs bound to the active site of the viral endonuclease by forming attractive intermolecular interactions with catalytically essential amino acid residues, His235, His250, and Lys290. Molecular dynamics simulation studies showed stable conformation dynamics upon drugs binding to endoU. The binding free energies for Glisoxepide and Idarubicin were calculated to be –141 ± 11 and –136 ± 16 kJ/mol, respectively. The IC50 were predicted to be 9.2 µM and 30 µM for Glisoxepide and Idarubicin, respectively. Comparative structural analysis showed the stronger binding of EndoU to Glisoxepide and Idarubicin than to uridine monophosphate (UMP). Surface area calculations showed buried are of 361.8Å2 by Glisoxepide which is almost double of the area occupied by UMP suggesting stronger binding of the drug than the ribonucleotide. However, further studies on these drugs for evaluation of their clinical efficacy and dose formulations may be required, which may provide a quick therapeutic option to treat COVID-19. Communicated by Ramaswamy H. Sarma

The outbreak of Coronavirus which initially began in China, in the year 2003 has caused several major public health concerns which resulted in epidemics globally, such as, severe acute respiratory syndrome (SARS) & Middle East respiratory syndrome (MERS). Most recently, i.e. in late December 2019, authorities identified an ongoing outbreak of the novel coronavirus (2019-nCoV), recently named as COVID-19 caused by SARS-CoV-2 which originated in Wuhan, Hubei Province, China. It probably marked the third highly pathogenic coronaviruses spreading globally, causing severe respiratory ailments and pneumonia-like infections in the humans.2019-nCoV exhibits similar genome organization, genetic, and epidemiological features to the other known CoVs. The COVID 19 virus has been declared as an inter-human transmissible virus which readily spreads mainly through the respiratory droplets produced when a person infected with coronavirus coughs, sneezes or talks. In a short stretch of time, this epidemic had spread to 210 Countries and Territories with 16, 20, 500 confirmed cases, including 97,400 confirmed deaths. Currently, the Mortality rate of COVID 19 is 2-5% only compared to SARS and MERS Coronaviruses. The older people are at a higher risk of COVID-19 infection due to their reduced immunity and body reserves, as well as multiple associated comorbidities like hypertension, diabetes, cancer and chronic obstructive pulmonary disorders. Till date, there is no effective anti-viral drug or licensed vaccine available to treat this infectious disease. As the infection is a recently advancing pathogen, several queries remain unanswered concerning the virus's reservoirs, pathogenesis, transmissibility, and much more is unknown. Herein, this article comprehensively reviews the currently available information on the virology, epidemiology, clinical presentation, diagnosis, and treatment of COVID-19.

T-cell acute lymphoblastic leukemia (T-ALL) is a genetically heterogeneous disease, characterized by an abnormal transformation of T cells into highly proliferative leukemic lymphoblasts. Identification of common genetic alterations has provided promising opportunities for better risk stratification in T-ALL. Current treatment in T-ALL still poses the major challenge of integrating the knowledge of molecular alterations in the clinical setting. We utilized the Multiplex Ligation Dependent Probe Amplification (MLPA) method to determine the frequency of common copy number alterations (CNAs) in 128 newly diagnosed T-ALL patients. We also studied the association of these CNAs with patient's clinical characteristics and survival. The highest frequency of deletion was observed in CDKN2A (59.38%), followed by CDKN2B (46.88%), LMO1 (37.5%), and MTAP (28.12%). PTPN2 (22.66%), PHF6 (14.06%), and MYB (14.06%) had the highest number of duplication events. A total of 89.06% patients exhibited CNAs. STIL::TAL1, NUP214::ABL1, and LMO2::RAG2 fusions were observed in 5.47%, 3.12%, and 0.78% of patients, respectively. CDKN2A, CDKN2B, and PTPN2 gene deletions were mainly observed in pediatric patients, while CNAs of NF1 and SUZ12 were observed more frequently in adults. In pediatric patients, alterations in CDKN2B, CASP8AP2, and AHI1 were associated with poor prognosis, while SUZ12 and NF1 CNAs were associated with favorable prognosis. In adult patients, ABL1 CNA emerged as an independent indicator of poor prognosis. The observed molecular heterogeneity in T-ALL may provide the basis for variations observed in clinical response in T-ALL and MLPA based CNA detection may help in risk stratification of these patients.

Dihydrouridination is one of the abundant modifications in tRNA editing. The presence of dihydrouridine is attributed to tRNA stability desired for the efficient gene translation process. The conversion of uridine to dihydrouridine is catalyzed by flavine containing enzyme called dihydrouridine synthase (Dus). We report first ever information about DusA enzyme from Pseudomonas aeruginosa in form of structural and functional studies. The gene coding for DusA from P. aeruginosa (PADusA) was cloned, expressed and purified, using recombinant DNA technology methods. Thermal and chemical stability of PADusA was determined with respect to temperature and urea-induced equilibrium unfolding experiments, with monitoring the change of ellipticity at 200–260 nm by Circular Dichroism (CD) spectroscopy. Unfolding studies revealed that PADusA has acquired a stable tertiary structure fold with a Tm value of 46.2 °C and Cm of 2.7 M for urea. The enzyme contains 43% α-helices and 16% β-strands. The three dimensional structure of PADusA was modeled using insilico methods. In order to understand the mechanism of substrate recognition and catalysis, tRNA and puromycin were docked on PADusA structure and their binding was analyzed. The structural features suggested that PADusA may also form a novel target for structure based drug design of antimicrobial agents.

Sperm-associated Antigen 5 (SPAG5, also called astrin) is a mitotic spindle protein. SPAG5 has emerged as a promising biomarker and therapeutic target in a variety of cancers. However, its expression and role in endometrial cancer (EC) remain to be studied. Using multi-omic authoritative datasets from the TCGA and CPTAC studies, we characterized theexpression, regulation of SPAG5 and its association with clinicopathological and molecular features in EC. SPAG5 was observed to be overexpressed in tumor tissues compared to controls and receiver operating characteristic analysis suggested that its mRNA levels are an excellent predictor of tumor presence (AUC>0.98). SPAG5 overexpression was associated with serous histology and The Cancer Genome Atlas (TCGA) defined molecular subtypes. Analysis of DNA methylation levels at SPAG5 genomic regions exhibiting negative correlation to SPAG5 expression. Further, SPAG5 expression was associated with copy number gain in EC. Univariate and multivariate survival analysis revealed that higher SPAG5 expression was independently associated with poor patient outcomes in EC. Additionally, gene set enrichment analysis of SPAG5 correlated genes revealed its association with numerous oncological pathways which suggest its critical involvement in this malignancy.

Severe Acute Respiratory Syndrome Corona Virus-2 (SARS-CoV2) is responsible for fetal pneumonia called COVID19. SARS-CoV2 emerged in Wuhan, Hubei Province of China in December 2019. The COVID19 pandemic has now gripped the entire world with more than 70 million cases and over 1.5 million deaths so far. There no treatment option for COVID19 is in term of a drug or vaccine is currently available. Therefore drug repurposing may only provide a quick method for utilizing existing drugs for a therapeutic option. The virus genome contains several non-structural proteins (NSP) which serve as target for designing of antiviral agents. NSP9 of SARS-CoV2 encodes for a replicase enzyme which is essential for the virus replication in the host cell. In search of potent inhibitors, we have screened FDA approved drugs against NSP9 using in silico methods. Five drugs fluspirilene, troglitazone, alvesco, dihydroergotoxine and avodart were found to have highest affinities with the replicase. The molecular dynamics simulation (MDS) studies demonstrated strong drugs binding and stable NSP9-drugs complexes formation. The findings are also strongly supported by root-mean-square deviation, root-mean-square fluctuation, radius of gyration, and hydrogen bond analysis of the complexes. Principal component analysis showed the stable conformation of NSP9 upon drug binding. It could be inferred that these five drugs individually or in combinations may be used as potential inhibitors of NSP9 of SARS-CoV-2 after exploring their in vivo antiviral potential.Communicated by Ramaswamy H. Sarma.

Regucalcin (RGN) regulates intracellular Ca

Serine-arginine protein kinase-1 (SRPK1) is a highly specific kinase that recognizes serine-arginine dipeptide repeats and phosphorylates SR rich splicing factor ASF/SF2 in a cell-cycle regulated manner. SRPK1 processively phosphorylates serine residues on its substrate ASF/SF2. Elevated expression pattern of both SRPK1 and ASF/SF2 and their association with various carcinomas have established SRPK1 as a potent target for drug design against cancers. In order to develop specific inhibitors the binding of ASF/SF2 to SRPK1 is desired to be selectively interrupted. We have performed molecular dynamics simulation studies on crystal structure of SRPK1 complex with ASF/SF2. The ASF/SF2 acquired a stable binding on the surface of SRPK1 with strong attractive forces. Analysis revealed that there was no major position shifting of the core β-sheet region within the catalytic site of SRPK1 when present in the state of ASF/SF2 bound in comparison to apo form. Global motions of SRPK1 indicated that major stable structural changes occurred after the substrate binding. The interactions between SRPK1 and ASF/SF2 were examined and calculated during molecular dynamics simulation of 1 µs. Molecular dynamics study indicated Arg84, Lys85, Leu86, Lys174, Tyr227 and Leu479 residues of SRPK1 as essential hot spots involved in the stable binding with substrate. Structural analysis of the binding affinity and hot spot investigation provided significant information on ASF/SF2 binding which may also be considered for designing of the novel specific inhibitors of SRPK1 for the applications in cancer therapy.Communicated by Ramaswamy H. Sarma.

Non-homologous End Joining (NHEJ) DNA damage repair pathway is the predominant pathway of DNA double-strand repair in human cells and its aberrant activity is associated with drug resistance in multiple cancers. However, the role of the NHEJ pathway in clear cell type of renal cell carcinoma (ccRCC) has been rarely addressed. We utilized authoritative databases of ccRCC containing multi-omics data, such as mutation, gene expression, DNA methylation, copy number alterations, and high throughput protein estimations to determine alterations in seven core NHEJ genes, including XRCC4, XRCC5, XRCC6, PRKDC, LIG4, NHEJ1, and PAXX. We further determined the association of their expression with clinicopathological features and molecular alterations in ccRCC. A comprehensive analysis of these genes revealed several alterations in the expression of these genes. Interestingly, NHEJ1 is downregulated and associated with better prognosis while PAXX is upregulated in ccRCC and associated with poor prognosis. These results suggest that alterations in DNA repair pathway are common in ccRCC and may provide novel therapeutic opportunities for this malignancy.

Poly(ADP-ribose) polymerase (PARP) is a critical nuclear enzyme which safeguards genome stability from genotoxic insults and helps in DNA repair. Inhibition of PARP results in sustained DNA damage in cancer cells. PARP inhibitors are known to play an important role in chemotherapy as single agents in many DNA repair pathway deficient tumor cells or in combination with several other chemotherapeutic agents. In the present study, we synthesize and characterize novel pyridazine derivatives, and evaluate their potential for use as PARP inhibitors. Results show that pyridazine derivatives inhibited the PARP1 enzymatic activity at the nanomolar range and showed anti-proliferative activity in leukemic cells. Interestingly, human leukemic cell line, Nalm6, in which PARP1 and PARP2 expression as well as intrinsic PARP activity are high, showed significant sensitivity for the novel inhibitors compared to other leukemic cells. Among the inhibitors, P10 showed maximum inhibition of intrinsic PARP activity and inhibited cell proliferation in Nalm6 cells. Besides P10 also showed maximum inhibition against purified PARP1 protein, which was comparable to olaparib in our assays. Newly synthesized compounds also showed remarkable DNA trapping ability, which is a signature feature of many PARP inhibitors. Importantly, P10 also induced late S and G2/M arrest in Nalm6 cells, indicating accumulation of DNA damage. Therefore, we identify P10 as a potential PARP inhibitor, which can be developed as a chemotherapeutic agent.

A leucine-rich protein, ARR19 (androgen receptor corepressor-19 kDa), is highly expressed in male reproductive organs and moderately in others. Previously, we have reported that ARR19 is differentially expressed in adult Leydig cells during the testis development and inhibits steroidogenesis by reducing the expression of steroidogenic enzymes. Whereas in prostate, ARR19 represses the transcriptional activity of AR (androgen receptor), it is important for male sexual differentiation and maturation in prostate and epididymis, through the recruitment of HDAC4. In this study we show that long term adenovirus mediated overexpression of ARR19 in mice testis has the potential of inhibiting the differentiation of testicular and prostatic cells by reducing the size of testis and prostate but has no effect on the growth of seminal vesicles. Further, it reduces the level of progesterone and testosterone by reducing the steroidogenic enzymes such as 3HSD, P450c17 and StAR. This is the first study reporting a time-course analysis of the implications of long term overexpression of ARR19 in mice testis and its effect on other organs such as prostate and seminal vesicles. Taken together, these results suggest that ARR19 may play an important role in the differentiation of male reproductive organs such as testis and prostate.