Diosgenin, a promising anticancer steroidal sapogenin, was isolated from Dioscorea deltoidea. Kee... more Diosgenin, a promising anticancer steroidal sapogenin, was isolated from Dioscorea deltoidea. Keeping its stereochemistry rich architecture intact, a scheme for the synthesis of novel diosgenin analogues was designed using Cu (I)-catalysed alkyne-azide cycloaddition in order to study their structure-activity relationship. Both diosgenin and its analogues exhibited interesting anti-proliferative effect against four human cancer cell lines viz. HBL-100 (breast), A549 (lung), HT-29 (colon) and HCT-116 (colon) using [3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazoliumbromide] (MTT) assay. Among the synthesized analogues, Dgn-1 bearing a simple phenyl R moiety attached via triazole to the parent molecule was identified as the most potent analogue against A549 cancer cell line having IC50 of 5.54μM, better than the positive control (BEZ-235). Dgn-2 and Dgn-5 bearing o-nitrophenyl and o-cyanophenyl R moieties respectively, displayed impressive anti-proliferative activity against all the tested human cancer cell lines with IC50 values ranging from 5.77 to 9.44μM. The structure-activity relationship (SAR) revealed that the analogues with simple phenyl R moiety or electron withdrawing ortho substituted R moieties seem to have beneficial impact on the anti-proliferative activity.
Journal of the Saudi Society of Agricultural Sciences, Oct 1, 2018
Jammu and Kashmir region of India has a rich walnut germplasm that has arisen from populations of... more Jammu and Kashmir region of India has a rich walnut germplasm that has arisen from populations of naturally grown seedlings and some introductions from other countries over many years. In this study, the genetic relatedness of 96 walnut genotypes adapted to the North Western Himalayan region of Jammu and Kashmir, India, was analyzed by 19 SSR markers. Genetic relationships among 96 walnut genotypes revealed very high polymorphism rate of 89.6%. Primer parameter values viz PIC, MI and Rp range from 0 to 0.43, 0 to 0.87 and 1.04 to 2.37 with an average of 0.168, 0.244 and 1.91 respectively. UPMGA dendrogram showed that all the accessions formed twelve main clusters with various degree of sub-clustering within the clusters. Model-based cluster analysis grouped 96 walnut genotypes into 5 genetically distinct sub-populations with varied level of admixture. Allele Frequency Divergence and expected heterozygosity vary from 0.00 to 0.057 and 0.043 to 0.067 with an average of 0.024 and 0.057 respectively between all the five populations. These studies will be helpful in association mapping studies for important traits in walnut. The high variability existing in the walnut germplasm suggested that it would be beneficial to utilize this germplasm pool in walnut breeding programs and germplasm management activities and also identified microsatellite markers for cultivar identification, characterization, registration and assessment in genebanks.
Biochimica Et Biophysica Acta - Proteins And Proteomics, Mar 1, 1992
Using a double modification technique about 20% of the lysine residues of bovine serum albumin (B... more Using a double modification technique about 20% of the lysine residues of bovine serum albumin (BSA) which are not easily accessible in the native protein have been modified. The technique involved = 80% modification of lysine residues of BSA with citraconic anhydride followed by chemical modification of the remaining lysine residues with acetic anhydride, succinic anhydride, potassium cyanate, or O-methylisourea. Finally, these preparations were decitraconylated under mild acidic conditions to yield acetylated, succinylated, carbomylated or guanidinated BSA. All of these preparations were found to be homogeneous with respect to charge and size. The spectral, hydrodynamic and bilirubin binding properties of these preparations are described. In contrast to most of the highly modified proteins these preparations with the exception of succinylated BSA are very similar to native BSA in their spectral and hydrodynamic properties. However, the equilibrium association constant (K a) with bilirubin measured by fluorescence quenching was decreased by about 100-fold in acetylated, carbamylated and succinylated BSA, but only 3-fold in guanidinated BSA. Since conformationally acetylated and carbamylated BSAs are identical to guanidinated lISA we conclude that the decrease in K a in these preparations is solely due to loss of positive charge on 'critical' lysine residues. The results support a binding model for BSA in which bilirubin binding site is buried and the protein undergoes a series of relaxationai changes in conformation upon interaction with bilirubin.
IRE1 is a transmembrane signalling protein that activates the unfolded protein response under end... more IRE1 is a transmembrane signalling protein that activates the unfolded protein response under endoplasmic reticulum stress. IRE1 is endowed with kinase and endoribonuclease activities. The ribonuclease activity of IRE1 can switch substrate specificities to carry out atypical splicing of Xbp1 mRNA or trigger the degradation of specific mRNAs. The mechanisms regulating the distinct ribonuclease activities of IRE1 have yet to be fully understood. Here, we report the Bcl‐2 family protein Bid as a novel recruit of the IRE1 complex, which directly interacts with the cytoplasmic domain of IRE1. Bid binding to IRE1 leads to a decrease in IRE1 phosphorylation in a way that it can only perform Xbp1 splicing while mRNA degradation activity is repressed. The RNase outputs of IRE1 have been found to regulate the homeostatic–apoptotic switch. This study, thus, provides insight into IRE1‐mediated cell survival.
Caulobacter crescentus, a Gram-negative alpha-proteobacterium, has surfaced as a powerful model s... more Caulobacter crescentus, a Gram-negative alpha-proteobacterium, has surfaced as a powerful model system for unraveling molecular networks that control the bacterial cell cycle. A straightforward synchronization protocol and existence of many well-defined developmental markers has allowed the identification of various molecular circuits that control the underlying differentiation processes executed at the level of transcription, translation, protein localization and dynamic proteolysis. The oligomeric AAA+ protease ClpXP is a well-characterized example of an enzyme that exerts post-translational control over a number of pathways. Also, the proteolytic pathways of its candidate proteins are reported to play significant roles in regulating cell cycle and protein quality control. A detailed evaluation of the impact of its proteolysis on various regulatory networks of the cell has uncovered various significant cellular roles of this protease in C. crescentus. A deeper insight into the eff...
UNC5B, PP2A, and netrin-1 are deregulated in a variety of cancers. UNC5B and PP2A are regarded as... more UNC5B, PP2A, and netrin-1 are deregulated in a variety of cancers. UNC5B and PP2A are regarded as tumor suppressors, as they promote apoptosis and are deleted or mutated in many cancers. In contrast, netrin-1 promotes survival by inhibiting dependence receptors, including UNC5B, and is upregulated in many cancers. Here, we show that UNC5B-mediated apoptosis can occur independently of p53 but in a PP2A-dependent manner. A substantial percentage of cancers arise due to p53 mutations and are insensitive to chemotherapeutic treatments that activate p53. Unexpectedly, treatment of cancers having functional p53 with many conventional drugs leads to the upregulation of netrin-1 through activated p53, which is counterintuitive. Therefore, understanding the p53-independent mechanisms of the netrin-UNC5B axis, such as those involving PP2A, assumes greater clinical significance. Anticancer strategies utilizing anti-netrin-1 antibody treatment are already in clinical trials.
a-Lactalbumin (a-La) gene is involved in milk production traits in dairy animals. The variability... more a-Lactalbumin (a-La) gene is involved in milk production traits in dairy animals. The variability in milk production potentials of different animals have been attributed to the polymorphism existing within this gene. The study was carried out to detect polymorphism in PCR amplified DNA fragments encompassing to-363 to +80 of the a-La gene in 50 Holstein Friesians (HF), 63 Jersey and 49 endogenous Kashmiri cattle. The polymorphism was detected by sequence analysis of amplified products. Three genotypes designated as AA, AB, BB were observed during the course of the study. The two alleles were differentiated on the basis of three single nucleotide polymorphism (SNP) each at position-250,-89, and-46 of the promoter region of the a-La gene. All the three nucleotide variations involved base transition viz, A to G, T to C and A to G, respectively. The haplotype with nucleotide A, T and A at positions-250,-89 and-46 was designated as A whereas the haplotype with nucleotide G, C and G at positions-250,-89 and-46 was designated as Allele B. The genotypic frequencies were observed to be 90.50 % (n=57) for AA allele and 9.50% (n=06) for AB allele in Jersey, however no animal with genotype of BB allele was observed. The genotypic frequencies of homozygous A, homozygous B and heterozygous AB were 30% (n=15), 22% (n=11) and 47% (n=23), respectively in Kashmiri cattle. Like in Jersey breed of cattle, no homozygous animal was observed to harbor BB genotype in HF cattle and the frequencies of AA and AB genotypes were 70% (n=35) and 30% (n=15), respectively. The allele frequencies for A and B allele were 95.25% and 4.75% in Jersey, 85% and 15% in HF and 54% and 46% in Kashmiri cattle, respectively. In view of the breed averages and preponderance of A allele in Bos tarus, it can be largely inferred that the polymorphism in 5' flanking region of the a-La gene could be a potential molecular marker for production traits in dairy cattle. However, to authenticate it further evaluation through association studies are warranted.
Biotechnology and molecular biology reviews, Aug 31, 2007
Proteases, though essentially indispensable to the maintenance and survival of their host organis... more Proteases, though essentially indispensable to the maintenance and survival of their host organisms, can be potentially damaging when overexpressed or present in higher concentrations, and their activities need to be correctly regulated. An important means of regulation involves modulation of their activities through interaction with substances, mostly proteins, called protease inhibitors. Some insects and many of the phytopathogenic microorganisms secrete extracellular enzymes and, in particular, enzymes causing proteolytic digestion of proteins, which play important roles in pathogenesis. Plants, however, have also developed mechanisms to fight these pathogenic organisms. One important line of defense that plants have to fight these pathogens is through various inhibitors that act against these proteolytic enzymes. These inhibitors are thus active in endogenous as well as exogenous defense systems. Protease inhibitors active against different mechanistic classes of proteases have been classified into different families on the basis of significant sequence similarities and structural relationships. Specific protease inhibitors are currently being overexpressed in certain transgenic plants to protect them against invaders. The current knowledge about plant protease inhibitors, their structure and their role in plant defense is briefly reviewed.
Present study reports the results of molecular analysis of the internal transcribed spacer (ITS) ... more Present study reports the results of molecular analysis of the internal transcribed spacer (ITS) of ribosomal DNA of 3 Monogenean species using polymerase chain reaction (PCR), nucleotide sequencing and construction of phylogenetic trees from different fish hosts of Kashmir. The present study shows that the size of the amplified product is 873 bp long for D. kashmirensis ; 1120 bp long in D . aegyptensis and 687 bp long in D. guptai revealing that there are intraspecific differences in their base pair lengths. Guanine and Cytocine (G+C) content of three Diplozoon species was found nearly constant for three species i.e ., 47% ( D. kashmirensis) ; 47% ( D. aegyptensis) and 48% ( D. guptai) , this GC richness contributes to physical attributes of RNA structures, as there is correlation between GC content and optimal growth temperature. An important observation during the present study has been noticed that Schizothorax niger is infected by all the three species of Diplozoidae: D. kashmirensis; D. aegyptensis and D. guptai, but when all six fishes were collected simultaneously, parasitism by all the parasite species was never observed. Phylogenetic trees Maximum Parsimony (MP), Maximum Likelihood (ML) and Neighbor Joining (NJ ) showed that D. kashmirensis and D. aegyptensis share a common host Carassius carassius and S. niger .
Parasite specimens of Diplozoon spp. were collected from the Carassius carassius; Cyprinus carpio... more Parasite specimens of Diplozoon spp. were collected from the Carassius carassius; Cyprinus carpio communis; C. c. specularis; Schizothorax niger; S. esocinus; S. curvifrons and S. plagiostomus of Kashmir and were used for DNA extraction. Samples were immediately fixed in 70% alcohol after collecting from the gills, gill cover, mouth cavity, eyes & fins of host fish. These samples were remained in alcohol until the present study. DNA isolation Parasite specimens of three Diplozoon species were collected from fish hosts of Carassius carassius; Cyprinus carpio communis;
Las trematodiasis zoonóticas han surgido a un ritmo rápido y frecuente con un importante costo hu... more Las trematodiasis zoonóticas han surgido a un ritmo rápido y frecuente con un importante costo humano y financiero. La más importante y conocida zoonosis humana causada por trematodos, que afectan al hígado es la fasciolosis. El presente trabajo ha sido realizado para tener una revisión exhaustiva de la extensa bibliografía sobre la fasciolosis en detalle que está aumentando rápidamente en incidencia y alcance geográfico. Las razones para el aumento de la infección por Fasciola spp son probablemente multifactoriales. El uso de la parasitoproteómica como un poderoso enfoque experimental, y sus potenciales beneficios para la biología de trematodos también se examinan en relación con el control futuro de las infecciones por trematodos en animales y en seres humanos. El objetivo es hacer a los jóvenes investigadores más vigilantes sobre la importancia de esta temática crítica. Los esfuerzos mundiales para ampliar la planificación conjunta, el intercambio de información, y el apoyo finan...
Mucor circinelloides serves as a model organism to investigate the lipid metabolism in oleaginous... more Mucor circinelloides serves as a model organism to investigate the lipid metabolism in oleaginous microorganisms. It is considered as an important producer of γ-linolenic acid (GLA) that has vital medicinal benefits. In this study, we used WJ11, a high lipid-producing strain of M. circinelloides (36% w/w lipid, cell dry weight, CDW), to examine the role in lipid accumulation of two mitochondrial malic enzyme (ME) genes malC and malD. The homologous overexpression of both malC and malD genes enhanced the total lipid content of WJ11 by 41.16 and 32.34%, respectively. In parallel, the total content of GLA was enhanced by 16.73 and 46.76% in malC and malD overexpressing strains, respectively, because of the elevation of total lipid content. The fact that GLA content was enhanced more in the strain with lower lipid content increase and vice versa, indicated that engineering of mitochondrial MEs altered the fatty acid profile. Our results reveal that mitochondrial ME plays an important ro...
Mutation Research-reviews in Mutation Research, Jul 1, 2017
Alpha-1-antitrypsin (AAT) is an acute phase secretory glycoprotein that inhibits neutrophil prote... more Alpha-1-antitrypsin (AAT) is an acute phase secretory glycoprotein that inhibits neutrophil proteases like elastase and is considered as the archetype of a family of structurally related serine protease inhibitors termed serpins. Serum AAT predominantly originates from liver and increases three to five fold during host response to tissue injury and inflammation. The AAT deficiency is unique among the protein misfolding diseases in that it causes target organ injury by both loss-of-function and gain-of-toxic function mechanisms. Lack of its antiprotease activity is associated with premature development of pulmonary emphysema and loss of function due to accumulation of resultant aggregates in chronic obstructive pulmonary disease (COPD). This in turn markedly reduces the amount of AAT that is available to protect lungs against proteolytic attack by the enzyme neutrophil elastase. The coalescence of AAT deficiency, its reduced efficacy, and cigarette smoking or poor ventilation conditions have devastating effect on lung function. On the other hand, the accumulation of retained mutant proteins in endoplasmic reticulum of liver cells in a polymerized form rather than secreted into the blood in its monomeric form is associated with chronic liver disease and predisposition to hepatocellular carcinoma (HCC) by gain of toxic function. Liver injury resulting from this gain-of-toxic function mechanism in which mutant AAT retained in the ER initiates a series of pathologic events, eventually culminating at liver cirrhosis and HCC. Here in this review, we underline the structural, genetic, polymorphic, biochemical and pathological advances made in the field of AAT deficiency and further comprehensively emphasis on the therapeutic interventions available for the patient.
Alpha1-antitrypsin (AAT) is one of the major circulating anti-protease whose levels in circulatio... more Alpha1-antitrypsin (AAT) is one of the major circulating anti-protease whose levels in circulation are raised during excessive amount of proteases, especially neutrophil elastase (NE) released during the course of inflammation. Proteolytic attack of NE on peripheral organs, more exclusively on lung parenchyma has severe consequence that may precipitate pulmonary emphysema. Normally, human body has its own molecular and physiological mechanisms to synthesize and regulate the production of antiprotease like AAT to mitigate the extent of inflammatory damage. AAT coded by serine-protease inhibitor (SERPINA1) is predominantly expressed in hepatocytes and to some extent by macrophages, monocytes, lung tissue etc. The observation that persons with AAT deficiency developed chronic obstructive pulmonary disease (COPD) and early-onset of emphysema proposed a role for pathways connecting AAT in pathogenesis. Extensive studies have been done till now to bridge a connection between numerous genetic polymorphisms of SERPINA1 gene and the early onset of COPD. Here in this review, we have comprehensively discussed some of the variants of SERPINA1 gene discovered till date and their association with the exacerbation of obstructive pulmonary disease.
International Journal of Biological Macromolecules, Sep 1, 2017
Expression and purification of p70 CT104 S6 K, a 72 KDa c-terminal truncated p70S6 kinase-GST fus... more Expression and purification of p70 CT104 S6 K, a 72 KDa c-terminal truncated p70S6 kinase-GST fusion protein in bacterial expression system,
Four alkaloid constituents: harmine, vasicine, vasicinone and harmaline were isolated and charact... more Four alkaloid constituents: harmine, vasicine, vasicinone and harmaline were isolated and characterized from Peganum harmala roots. Harmine showed the best cytotoxicity with IC 50 of 32, 106, 45, 33 and 61 mM against breast (HBL-100), lung (A549), colon (HT-29 & HCT-116) and cervical (HELA) cells respectively. The harmine analogs, synthesized via click chemistry, revealed that few derivatives possess potent cytotoxic effects. m-Fluoro phenyl-1, 2,3-triazolyl harmine was found to be selectively cytotoxic against human breast cancer cell lines only displaying an IC 50 of 16mM. p-Fluoro phenyl-1,2,3-triazolyl harmine and p-methoxy phenyl-1,2,3-triazolyl harmine displayed improved cytotoxicity. p-Fluorophenyl-1,2,3-triazolyl harmine displayed broad spectrum cytotoxic effects against all the tested cancer-cell lines with IC 50 of 17, 19, 29 and 17mM against lung (A-549), Colon (HT-29), Cervic (HELA) and Colon (HCT-116) cell lines respectively while as p-methoxy phenyl-1,2,3-triazolyl harmine showed selectivity towards lung and colon cancer cell lines with IC 50 of 27, 18 and 17mM against A549, HT-29 and HCT-116 respectively.
Furin cleavage-site (CS) present between the S1/S2 junction in SARS-CoV2 spike (S) protein is cri... more Furin cleavage-site (CS) present between the S1/S2 junction in SARS-CoV2 spike (S) protein is critical to drive the fusion of SARS-CoV2 with the host cell. SARS-CoV2 falls in the sarbecovirus lineage that doesn't comprise of furin CS and therefore makes its origin enigmatic. The available wild-type (Wt) SARS-CoV2 S protein with PDB ID: 6yvb lacks a stretch of amino acid including furin CS as well. All investigators till date have shown this stretch existing in the form of a loop. We are for the rst time reporting that this stretch comprises of 14 amino acid residues (677QTNSPRRARSVASQ689), forming an antiparallel βsheet comprising of PRRAR furin CS. We observed the presence of this antiparallel β-sheet in MERS spike protein as well. While switching over from Wt. SARS-CoV2 with PRRAR furin CS to B.1.1.7 variant with HRRAR furin CS, we found 3% increase in the percentage content of β stands. Interestingly, we found that the change of B.1.1.7 to B.1.617 variant comprising of RRRAR furin CS shifted the percentage secondary structure back to that found in Wt. SARS-CoV2. We anticipate that this β-sheet is used as a docking site by host cell proteases to act on furin-CS. Additionally, we studied the interaction of modeled SARS-CoV2 S protein with transmembrane protease, serine 2 (TMPRSS2), and furin proteases, which clearly highlighted that these proteases exclusively uses furin CS located in β-sheet to cleave the SARS-CoV2 S protein at its S1/S2 junction. Supplementary Files This is a list of supplementary les associated with this preprint. Click to download. Cefadroxil.mpg Cefazolinsodium.mpg Cefpodoximeproxetil.mpg Ceftazidime.mpg Ceftriaxone.mpg Cefuroxime.mpg Cephalexin.mpg Ceftriaxonewithmutant.mpg Cephalexinwithmutant.mpg Remdesivir.mpg Zanamivir.mpg Zidovudine.mpg
Diosgenin, a promising anticancer steroidal sapogenin, was isolated from Dioscorea deltoidea. Kee... more Diosgenin, a promising anticancer steroidal sapogenin, was isolated from Dioscorea deltoidea. Keeping its stereochemistry rich architecture intact, a scheme for the synthesis of novel diosgenin analogues was designed using Cu (I)-catalysed alkyne-azide cycloaddition in order to study their structure-activity relationship. Both diosgenin and its analogues exhibited interesting anti-proliferative effect against four human cancer cell lines viz. HBL-100 (breast), A549 (lung), HT-29 (colon) and HCT-116 (colon) using [3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazoliumbromide] (MTT) assay. Among the synthesized analogues, Dgn-1 bearing a simple phenyl R moiety attached via triazole to the parent molecule was identified as the most potent analogue against A549 cancer cell line having IC50 of 5.54μM, better than the positive control (BEZ-235). Dgn-2 and Dgn-5 bearing o-nitrophenyl and o-cyanophenyl R moieties respectively, displayed impressive anti-proliferative activity against all the tested human cancer cell lines with IC50 values ranging from 5.77 to 9.44μM. The structure-activity relationship (SAR) revealed that the analogues with simple phenyl R moiety or electron withdrawing ortho substituted R moieties seem to have beneficial impact on the anti-proliferative activity.
Journal of the Saudi Society of Agricultural Sciences, Oct 1, 2018
Jammu and Kashmir region of India has a rich walnut germplasm that has arisen from populations of... more Jammu and Kashmir region of India has a rich walnut germplasm that has arisen from populations of naturally grown seedlings and some introductions from other countries over many years. In this study, the genetic relatedness of 96 walnut genotypes adapted to the North Western Himalayan region of Jammu and Kashmir, India, was analyzed by 19 SSR markers. Genetic relationships among 96 walnut genotypes revealed very high polymorphism rate of 89.6%. Primer parameter values viz PIC, MI and Rp range from 0 to 0.43, 0 to 0.87 and 1.04 to 2.37 with an average of 0.168, 0.244 and 1.91 respectively. UPMGA dendrogram showed that all the accessions formed twelve main clusters with various degree of sub-clustering within the clusters. Model-based cluster analysis grouped 96 walnut genotypes into 5 genetically distinct sub-populations with varied level of admixture. Allele Frequency Divergence and expected heterozygosity vary from 0.00 to 0.057 and 0.043 to 0.067 with an average of 0.024 and 0.057 respectively between all the five populations. These studies will be helpful in association mapping studies for important traits in walnut. The high variability existing in the walnut germplasm suggested that it would be beneficial to utilize this germplasm pool in walnut breeding programs and germplasm management activities and also identified microsatellite markers for cultivar identification, characterization, registration and assessment in genebanks.
Biochimica Et Biophysica Acta - Proteins And Proteomics, Mar 1, 1992
Using a double modification technique about 20% of the lysine residues of bovine serum albumin (B... more Using a double modification technique about 20% of the lysine residues of bovine serum albumin (BSA) which are not easily accessible in the native protein have been modified. The technique involved = 80% modification of lysine residues of BSA with citraconic anhydride followed by chemical modification of the remaining lysine residues with acetic anhydride, succinic anhydride, potassium cyanate, or O-methylisourea. Finally, these preparations were decitraconylated under mild acidic conditions to yield acetylated, succinylated, carbomylated or guanidinated BSA. All of these preparations were found to be homogeneous with respect to charge and size. The spectral, hydrodynamic and bilirubin binding properties of these preparations are described. In contrast to most of the highly modified proteins these preparations with the exception of succinylated BSA are very similar to native BSA in their spectral and hydrodynamic properties. However, the equilibrium association constant (K a) with bilirubin measured by fluorescence quenching was decreased by about 100-fold in acetylated, carbamylated and succinylated BSA, but only 3-fold in guanidinated BSA. Since conformationally acetylated and carbamylated BSAs are identical to guanidinated lISA we conclude that the decrease in K a in these preparations is solely due to loss of positive charge on 'critical' lysine residues. The results support a binding model for BSA in which bilirubin binding site is buried and the protein undergoes a series of relaxationai changes in conformation upon interaction with bilirubin.
IRE1 is a transmembrane signalling protein that activates the unfolded protein response under end... more IRE1 is a transmembrane signalling protein that activates the unfolded protein response under endoplasmic reticulum stress. IRE1 is endowed with kinase and endoribonuclease activities. The ribonuclease activity of IRE1 can switch substrate specificities to carry out atypical splicing of Xbp1 mRNA or trigger the degradation of specific mRNAs. The mechanisms regulating the distinct ribonuclease activities of IRE1 have yet to be fully understood. Here, we report the Bcl‐2 family protein Bid as a novel recruit of the IRE1 complex, which directly interacts with the cytoplasmic domain of IRE1. Bid binding to IRE1 leads to a decrease in IRE1 phosphorylation in a way that it can only perform Xbp1 splicing while mRNA degradation activity is repressed. The RNase outputs of IRE1 have been found to regulate the homeostatic–apoptotic switch. This study, thus, provides insight into IRE1‐mediated cell survival.
Caulobacter crescentus, a Gram-negative alpha-proteobacterium, has surfaced as a powerful model s... more Caulobacter crescentus, a Gram-negative alpha-proteobacterium, has surfaced as a powerful model system for unraveling molecular networks that control the bacterial cell cycle. A straightforward synchronization protocol and existence of many well-defined developmental markers has allowed the identification of various molecular circuits that control the underlying differentiation processes executed at the level of transcription, translation, protein localization and dynamic proteolysis. The oligomeric AAA+ protease ClpXP is a well-characterized example of an enzyme that exerts post-translational control over a number of pathways. Also, the proteolytic pathways of its candidate proteins are reported to play significant roles in regulating cell cycle and protein quality control. A detailed evaluation of the impact of its proteolysis on various regulatory networks of the cell has uncovered various significant cellular roles of this protease in C. crescentus. A deeper insight into the eff...
UNC5B, PP2A, and netrin-1 are deregulated in a variety of cancers. UNC5B and PP2A are regarded as... more UNC5B, PP2A, and netrin-1 are deregulated in a variety of cancers. UNC5B and PP2A are regarded as tumor suppressors, as they promote apoptosis and are deleted or mutated in many cancers. In contrast, netrin-1 promotes survival by inhibiting dependence receptors, including UNC5B, and is upregulated in many cancers. Here, we show that UNC5B-mediated apoptosis can occur independently of p53 but in a PP2A-dependent manner. A substantial percentage of cancers arise due to p53 mutations and are insensitive to chemotherapeutic treatments that activate p53. Unexpectedly, treatment of cancers having functional p53 with many conventional drugs leads to the upregulation of netrin-1 through activated p53, which is counterintuitive. Therefore, understanding the p53-independent mechanisms of the netrin-UNC5B axis, such as those involving PP2A, assumes greater clinical significance. Anticancer strategies utilizing anti-netrin-1 antibody treatment are already in clinical trials.
a-Lactalbumin (a-La) gene is involved in milk production traits in dairy animals. The variability... more a-Lactalbumin (a-La) gene is involved in milk production traits in dairy animals. The variability in milk production potentials of different animals have been attributed to the polymorphism existing within this gene. The study was carried out to detect polymorphism in PCR amplified DNA fragments encompassing to-363 to +80 of the a-La gene in 50 Holstein Friesians (HF), 63 Jersey and 49 endogenous Kashmiri cattle. The polymorphism was detected by sequence analysis of amplified products. Three genotypes designated as AA, AB, BB were observed during the course of the study. The two alleles were differentiated on the basis of three single nucleotide polymorphism (SNP) each at position-250,-89, and-46 of the promoter region of the a-La gene. All the three nucleotide variations involved base transition viz, A to G, T to C and A to G, respectively. The haplotype with nucleotide A, T and A at positions-250,-89 and-46 was designated as A whereas the haplotype with nucleotide G, C and G at positions-250,-89 and-46 was designated as Allele B. The genotypic frequencies were observed to be 90.50 % (n=57) for AA allele and 9.50% (n=06) for AB allele in Jersey, however no animal with genotype of BB allele was observed. The genotypic frequencies of homozygous A, homozygous B and heterozygous AB were 30% (n=15), 22% (n=11) and 47% (n=23), respectively in Kashmiri cattle. Like in Jersey breed of cattle, no homozygous animal was observed to harbor BB genotype in HF cattle and the frequencies of AA and AB genotypes were 70% (n=35) and 30% (n=15), respectively. The allele frequencies for A and B allele were 95.25% and 4.75% in Jersey, 85% and 15% in HF and 54% and 46% in Kashmiri cattle, respectively. In view of the breed averages and preponderance of A allele in Bos tarus, it can be largely inferred that the polymorphism in 5' flanking region of the a-La gene could be a potential molecular marker for production traits in dairy cattle. However, to authenticate it further evaluation through association studies are warranted.
Biotechnology and molecular biology reviews, Aug 31, 2007
Proteases, though essentially indispensable to the maintenance and survival of their host organis... more Proteases, though essentially indispensable to the maintenance and survival of their host organisms, can be potentially damaging when overexpressed or present in higher concentrations, and their activities need to be correctly regulated. An important means of regulation involves modulation of their activities through interaction with substances, mostly proteins, called protease inhibitors. Some insects and many of the phytopathogenic microorganisms secrete extracellular enzymes and, in particular, enzymes causing proteolytic digestion of proteins, which play important roles in pathogenesis. Plants, however, have also developed mechanisms to fight these pathogenic organisms. One important line of defense that plants have to fight these pathogens is through various inhibitors that act against these proteolytic enzymes. These inhibitors are thus active in endogenous as well as exogenous defense systems. Protease inhibitors active against different mechanistic classes of proteases have been classified into different families on the basis of significant sequence similarities and structural relationships. Specific protease inhibitors are currently being overexpressed in certain transgenic plants to protect them against invaders. The current knowledge about plant protease inhibitors, their structure and their role in plant defense is briefly reviewed.
Present study reports the results of molecular analysis of the internal transcribed spacer (ITS) ... more Present study reports the results of molecular analysis of the internal transcribed spacer (ITS) of ribosomal DNA of 3 Monogenean species using polymerase chain reaction (PCR), nucleotide sequencing and construction of phylogenetic trees from different fish hosts of Kashmir. The present study shows that the size of the amplified product is 873 bp long for D. kashmirensis ; 1120 bp long in D . aegyptensis and 687 bp long in D. guptai revealing that there are intraspecific differences in their base pair lengths. Guanine and Cytocine (G+C) content of three Diplozoon species was found nearly constant for three species i.e ., 47% ( D. kashmirensis) ; 47% ( D. aegyptensis) and 48% ( D. guptai) , this GC richness contributes to physical attributes of RNA structures, as there is correlation between GC content and optimal growth temperature. An important observation during the present study has been noticed that Schizothorax niger is infected by all the three species of Diplozoidae: D. kashmirensis; D. aegyptensis and D. guptai, but when all six fishes were collected simultaneously, parasitism by all the parasite species was never observed. Phylogenetic trees Maximum Parsimony (MP), Maximum Likelihood (ML) and Neighbor Joining (NJ ) showed that D. kashmirensis and D. aegyptensis share a common host Carassius carassius and S. niger .
Parasite specimens of Diplozoon spp. were collected from the Carassius carassius; Cyprinus carpio... more Parasite specimens of Diplozoon spp. were collected from the Carassius carassius; Cyprinus carpio communis; C. c. specularis; Schizothorax niger; S. esocinus; S. curvifrons and S. plagiostomus of Kashmir and were used for DNA extraction. Samples were immediately fixed in 70% alcohol after collecting from the gills, gill cover, mouth cavity, eyes & fins of host fish. These samples were remained in alcohol until the present study. DNA isolation Parasite specimens of three Diplozoon species were collected from fish hosts of Carassius carassius; Cyprinus carpio communis;
Las trematodiasis zoonóticas han surgido a un ritmo rápido y frecuente con un importante costo hu... more Las trematodiasis zoonóticas han surgido a un ritmo rápido y frecuente con un importante costo humano y financiero. La más importante y conocida zoonosis humana causada por trematodos, que afectan al hígado es la fasciolosis. El presente trabajo ha sido realizado para tener una revisión exhaustiva de la extensa bibliografía sobre la fasciolosis en detalle que está aumentando rápidamente en incidencia y alcance geográfico. Las razones para el aumento de la infección por Fasciola spp son probablemente multifactoriales. El uso de la parasitoproteómica como un poderoso enfoque experimental, y sus potenciales beneficios para la biología de trematodos también se examinan en relación con el control futuro de las infecciones por trematodos en animales y en seres humanos. El objetivo es hacer a los jóvenes investigadores más vigilantes sobre la importancia de esta temática crítica. Los esfuerzos mundiales para ampliar la planificación conjunta, el intercambio de información, y el apoyo finan...
Mucor circinelloides serves as a model organism to investigate the lipid metabolism in oleaginous... more Mucor circinelloides serves as a model organism to investigate the lipid metabolism in oleaginous microorganisms. It is considered as an important producer of γ-linolenic acid (GLA) that has vital medicinal benefits. In this study, we used WJ11, a high lipid-producing strain of M. circinelloides (36% w/w lipid, cell dry weight, CDW), to examine the role in lipid accumulation of two mitochondrial malic enzyme (ME) genes malC and malD. The homologous overexpression of both malC and malD genes enhanced the total lipid content of WJ11 by 41.16 and 32.34%, respectively. In parallel, the total content of GLA was enhanced by 16.73 and 46.76% in malC and malD overexpressing strains, respectively, because of the elevation of total lipid content. The fact that GLA content was enhanced more in the strain with lower lipid content increase and vice versa, indicated that engineering of mitochondrial MEs altered the fatty acid profile. Our results reveal that mitochondrial ME plays an important ro...
Mutation Research-reviews in Mutation Research, Jul 1, 2017
Alpha-1-antitrypsin (AAT) is an acute phase secretory glycoprotein that inhibits neutrophil prote... more Alpha-1-antitrypsin (AAT) is an acute phase secretory glycoprotein that inhibits neutrophil proteases like elastase and is considered as the archetype of a family of structurally related serine protease inhibitors termed serpins. Serum AAT predominantly originates from liver and increases three to five fold during host response to tissue injury and inflammation. The AAT deficiency is unique among the protein misfolding diseases in that it causes target organ injury by both loss-of-function and gain-of-toxic function mechanisms. Lack of its antiprotease activity is associated with premature development of pulmonary emphysema and loss of function due to accumulation of resultant aggregates in chronic obstructive pulmonary disease (COPD). This in turn markedly reduces the amount of AAT that is available to protect lungs against proteolytic attack by the enzyme neutrophil elastase. The coalescence of AAT deficiency, its reduced efficacy, and cigarette smoking or poor ventilation conditions have devastating effect on lung function. On the other hand, the accumulation of retained mutant proteins in endoplasmic reticulum of liver cells in a polymerized form rather than secreted into the blood in its monomeric form is associated with chronic liver disease and predisposition to hepatocellular carcinoma (HCC) by gain of toxic function. Liver injury resulting from this gain-of-toxic function mechanism in which mutant AAT retained in the ER initiates a series of pathologic events, eventually culminating at liver cirrhosis and HCC. Here in this review, we underline the structural, genetic, polymorphic, biochemical and pathological advances made in the field of AAT deficiency and further comprehensively emphasis on the therapeutic interventions available for the patient.
Alpha1-antitrypsin (AAT) is one of the major circulating anti-protease whose levels in circulatio... more Alpha1-antitrypsin (AAT) is one of the major circulating anti-protease whose levels in circulation are raised during excessive amount of proteases, especially neutrophil elastase (NE) released during the course of inflammation. Proteolytic attack of NE on peripheral organs, more exclusively on lung parenchyma has severe consequence that may precipitate pulmonary emphysema. Normally, human body has its own molecular and physiological mechanisms to synthesize and regulate the production of antiprotease like AAT to mitigate the extent of inflammatory damage. AAT coded by serine-protease inhibitor (SERPINA1) is predominantly expressed in hepatocytes and to some extent by macrophages, monocytes, lung tissue etc. The observation that persons with AAT deficiency developed chronic obstructive pulmonary disease (COPD) and early-onset of emphysema proposed a role for pathways connecting AAT in pathogenesis. Extensive studies have been done till now to bridge a connection between numerous genetic polymorphisms of SERPINA1 gene and the early onset of COPD. Here in this review, we have comprehensively discussed some of the variants of SERPINA1 gene discovered till date and their association with the exacerbation of obstructive pulmonary disease.
International Journal of Biological Macromolecules, Sep 1, 2017
Expression and purification of p70 CT104 S6 K, a 72 KDa c-terminal truncated p70S6 kinase-GST fus... more Expression and purification of p70 CT104 S6 K, a 72 KDa c-terminal truncated p70S6 kinase-GST fusion protein in bacterial expression system,
Four alkaloid constituents: harmine, vasicine, vasicinone and harmaline were isolated and charact... more Four alkaloid constituents: harmine, vasicine, vasicinone and harmaline were isolated and characterized from Peganum harmala roots. Harmine showed the best cytotoxicity with IC 50 of 32, 106, 45, 33 and 61 mM against breast (HBL-100), lung (A549), colon (HT-29 & HCT-116) and cervical (HELA) cells respectively. The harmine analogs, synthesized via click chemistry, revealed that few derivatives possess potent cytotoxic effects. m-Fluoro phenyl-1, 2,3-triazolyl harmine was found to be selectively cytotoxic against human breast cancer cell lines only displaying an IC 50 of 16mM. p-Fluoro phenyl-1,2,3-triazolyl harmine and p-methoxy phenyl-1,2,3-triazolyl harmine displayed improved cytotoxicity. p-Fluorophenyl-1,2,3-triazolyl harmine displayed broad spectrum cytotoxic effects against all the tested cancer-cell lines with IC 50 of 17, 19, 29 and 17mM against lung (A-549), Colon (HT-29), Cervic (HELA) and Colon (HCT-116) cell lines respectively while as p-methoxy phenyl-1,2,3-triazolyl harmine showed selectivity towards lung and colon cancer cell lines with IC 50 of 27, 18 and 17mM against A549, HT-29 and HCT-116 respectively.
Furin cleavage-site (CS) present between the S1/S2 junction in SARS-CoV2 spike (S) protein is cri... more Furin cleavage-site (CS) present between the S1/S2 junction in SARS-CoV2 spike (S) protein is critical to drive the fusion of SARS-CoV2 with the host cell. SARS-CoV2 falls in the sarbecovirus lineage that doesn't comprise of furin CS and therefore makes its origin enigmatic. The available wild-type (Wt) SARS-CoV2 S protein with PDB ID: 6yvb lacks a stretch of amino acid including furin CS as well. All investigators till date have shown this stretch existing in the form of a loop. We are for the rst time reporting that this stretch comprises of 14 amino acid residues (677QTNSPRRARSVASQ689), forming an antiparallel βsheet comprising of PRRAR furin CS. We observed the presence of this antiparallel β-sheet in MERS spike protein as well. While switching over from Wt. SARS-CoV2 with PRRAR furin CS to B.1.1.7 variant with HRRAR furin CS, we found 3% increase in the percentage content of β stands. Interestingly, we found that the change of B.1.1.7 to B.1.617 variant comprising of RRRAR furin CS shifted the percentage secondary structure back to that found in Wt. SARS-CoV2. We anticipate that this β-sheet is used as a docking site by host cell proteases to act on furin-CS. Additionally, we studied the interaction of modeled SARS-CoV2 S protein with transmembrane protease, serine 2 (TMPRSS2), and furin proteases, which clearly highlighted that these proteases exclusively uses furin CS located in β-sheet to cleave the SARS-CoV2 S protein at its S1/S2 junction. Supplementary Files This is a list of supplementary les associated with this preprint. Click to download. Cefadroxil.mpg Cefazolinsodium.mpg Cefpodoximeproxetil.mpg Ceftazidime.mpg Ceftriaxone.mpg Cefuroxime.mpg Cephalexin.mpg Ceftriaxonewithmutant.mpg Cephalexinwithmutant.mpg Remdesivir.mpg Zanamivir.mpg Zidovudine.mpg
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