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Gupta, N.

Publications and source records attributed to Gupta, N..

At least 73 records · Page 4Linked to original sources

The CIC-ERF co-deletion underlies fusion independent activation of ETS family member, ETV1, to drive prostate cancer progression

The dysregulation of ETS family transcription factors drives human prostate cancer. The majority of prostate cancer is the result of chromosomal rearrangements that lead to aberrant ETS gene expression. The mechanisms that lead to fusion independent ETS factor upregulation and prostate oncogenesis remain unknown. Here, we show that two neighboring transcription factors, Capicua (CIC) and ETS2 repressor factor (ERF), which are co-deleted in human prostate tumors can drive prostate oncogenesis. Concurrent CIC and ERF loss commonly occurs through focal genomic deletions at chromosome 19q13.2. Mechanistically, CIC and ERF co-bind the proximal regulatory element and mutually repress the ETS transcription factor, ETV1. Targeting ETV1 in CIC and ERF deficient prostate cancer limits tumor growth. Thus, we have uncovered a fusion independent mode of ETS transcriptional activation defined by concurrent loss of CIC and ERF.

cancer biology↗

Mosquito Olfactory Response Ensemble: a curated database of behavioral and electrophysiological responses enables pattern discovery

Many experimental studies have examined behavioral and electrophysiological responses of mosquitoes to odors. However, the differences across studies in data collection, processing, and reporting make it difficult to perform large-scale analyses combining data from multiple studies. Here we extract and standardize data for 12 mosquito species, along with Drosophila melanogaster for comparison, from over 170 studies and curate the Mosquito Olfactory Response Ensemble (MORE), publicly available at https://neuralsystems.github.io/MORE. We demonstrate the ability of MORE in generating biological insights by finding patterns across studies. Our analyses reveal that ORs are tuned to specific ranges of several physicochemical properties of odorants; the empty-neuron recording technique for measuring OR responses is more sensitive than the Xenopus oocyte technique; there are systematic differences in the behavioral preferences reported by different types of assays; and odorants tend to become less attractive or more aversive at higher concentrations.

neuroscience↗

An in vitro and in vivo approach for the isolation of Omicron variant from human clinical specimens

Due to failure of virus isolation of Omicron variant in Vero CCL-81 from the clinical specimens of COVID-19 cases, we infected Syrian hamsters and then passage into Vero CCL-81 cells. The Omicron sequences were studied to assess if hamster could incorporate any mutation to changes its susceptibility. L212C mutation, Tyrosine 69 deletion, and C25000T nucleotide change in spike gene and absence of V17I mutation in E gene was observed in sequences of hamster passage unlike human clinical specimen and Vero CCL-81 passages. No change was observed in the furin cleavage site in any of the specimen sequence which suggests usefulness of these isolates in future studies.

microbiology↗

Cancer/Testis genes are predictive of breast tumor subtypes

Breast cancer is the most prevalent type of cancer in women worldwide. Within breast tumors, the basal-like subtype has the worst prognosis and no dedicated therapy, therefore new tools to understand, detect, and treat these tumors are needed. Certain germline genes are re-expressed in tumors, and constitute the Cancer/Testis genes; their misexpression has diagnostic and therapeutic applications. Here, we designed a new approach to examine Cancer/ Testis gene misexpression in breast tumors. We identify several new markers in Luminal and HER-2 positive tumors, some of which predict response to chemotherapy. We then use machine learning to identify the 2 Cancer/Testis genes most associated with basal-like breast tumors: HORMAD1 and CT83. We show that these genes are expressed by tumor cells but not the microenvironment, and that they are not expressed by normal breast progenitors, in other words their activation occurs de novo. We find these genes are epigenetically repressed by DNA methylation, and that their activation upon DNA demethylation is irreversible, providing a memory of past epigenetic disturbances. Basal-like tumors expressing both genes have a poorer outcome than tumors expressing either gene alone or neither gene. Therefore, these findings suggest a potential synergistic effect between Cancer/Testis genes in basal breast tumors; these findings have consequences for the understanding, diagnosis, and therapy of the breast tumors with the worse outcomes.

cancer biology↗

Microbial induced calcite precipitation can consolidate martian and lunar regolith simulants

We demonstrate that Microbial Induced Calcite Precipitation (MICP) can be utilized for creation of consolidates of Martian Simulant Soil (MSS) and Lunar Simulant Soil (LSS) in the form of a brick. A urease producer bacteria, Sporosarcina pasteurii, was used to induce the MICP process for the both simulant soils. An admixture of guar gum as an organic polymer and NiCl2, as bio-catalyst to enhance urease activity, was introduced to increase the compressive strength of the biologically grown bricks. A casting method was utilized for a slurry consisting of the appropriate simulant soil and microbe; the slurry over a few days consolidated in the form of a brick of the desired shape. In case of MSS, maximum strength of 3.3 MPa was obtained with 10mM NiCl2 and 1% guar gum supplementation whereas in case of LSS maximum strength of 5.65 MPa was obtained with 1% guar gum supplementation and 10mM NiCl2. MICP mediated consolidation of the simulant soil was confirmed with field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). Our work demonstrates a biological approach with an explicit casting method towards manufacturing of consolidated structures using extra-terrestrial regolith simulant; this is a promising route for in situ development of structural elements on the extra-terrestrial habitats.

bioengineering↗

Spexin modulates molecular thermogenic profile of adipose tissue and thermoregulatory behaviors

Thermoregulation is a physiological process by which a mammal regulates body temperature in response to its environment. Within the human body, thermoregulatory behaviors and metabolism are modulated by circulating metabolic factors. In our study, we tested the ability of the neuropeptide spexin, which shares sequence homology to galanin, to regulate these functions in female mice. Supraphysiological levels of spexin in C57BL/6 mice were insufficient to protect against diet-induced obesity after 50 days of treatment. Behavioral analysis of long-term spexin treatment appeared to modulate anxiety-like behaviors by promoting exploratory behaviors and thermoregulatory behaviors of nest building that ceased when animals were housed at thermoneutral temperatures. Upon examination of the molecular profile of brown and white adipose tissue, treatment disrupted the thermogenic profile of white adipose tissue, in which {beta}3-adrenergic receptor expression was downregulated. Our results reveal novel functions for spexin as a modulator of thermoregulatory behaviors and adipose tissue metabolism. HighlightsO_LISpexin treatment did not protect against diet-induced obesity in female mice. C_LIO_LISpexin-treatment promoted thermoregulatory behaviors of nest building. C_LIO_LIBehaviors normalized when animals were housed in thermoneutral temperatures. C_LI Funding SourcesNot applicable Disclosure SummaryNothing to disclose

molecular biology↗

Gene expression in African Americans and Latinos reveals ancestry-specific patterns of genetic architecture

We analyzed whole genome and RNA sequencing data from 2,733 African American and Hispanic/Latino children to explore ancestry- and heterozygosity-related differences in the genetic architecture of whole blood gene expression. We found that heritability of gene expression significantly increases with greater proportion of African genetic ancestry and decreases with higher levels of Indigenous American ancestry, consistent with a relationship between heterozygosity and genetic variance. Among heritable protein-coding genes, the prevalence of statistically significant ancestry-specific expression quantitative trait loci (anc-eQTLs) was 30% in African ancestry and 8% for Indigenous American ancestry segments. Most of the anc-eQTLs (89%) were driven by population differences in allele frequency, demonstrating the importance of measuring gene expression across multiple populations. Transcriptome-wide association analyses of multi-ancestry summary statistics for 28 traits identified 79% more gene-trait pairs using models trained in our admixed population than models trained in GTEx. Our study highlights the importance of large and ancestrally diverse genomic studies for enabling new discoveries of complex trait architecture and reducing disparities.

genetics↗

Comparative secretomics identifies conserved WAxR motif-containing effectors in rust fungi that suppress cell death in plants

Identification of novel effectors with conserved features has always remained a challenge in plant-pathogen interaction studies. The introduction of the genomics era in plant-pathogen studies has led to the identification of significant candidate effectors with novel motifs such as RxLR and dEER motifs. However, in the case of fungal pathogens, limited conserved motifs associated with effectors have been discovered yet. In the present study, we have performed comparative secretome analysis for major plant pathogens of diverse nutrition mechanisms with the aim of dissecting the features underlying their corresponding secretome and conserved motifs. We showed that rust fungi possess the lowest Cell wall degrading enzymes (CWDEs) consortium lower than other biotrophic pathogens. We also showed rust fungi possess the highest secretory superoxide dismutase (SOD) than other studied plant pathogens. Further, we prioritized the candidate secretory effectors proteins (CSEPs) of all the studied pathogens by combining various effector mining parameters to highlight the candidates with potential effector features. A novel WAxR motif in conjugation with the Y/F/WxC (FGC) motif was identified in the effectors of various P. striiformis races present globally. The WAxR/WAxR like motifs ( WxxR, WAxx, xAxR) containing effectors were also found in the secretome of other rust fungi. Further, the functional validation of two candidate effectors with WAxR motif from P. striiformis Yr9 showed that these effectors localize to the nucleus as well as cytoplasm, and are able to suppress BAX induced cell death in Nicotiana benthamiana. The mutation analysis of individual residues of the WAxR motif (W, A, R) however did not affect the cell death suppression nor subcellular localization of these effectors. Overall, the current study reports the presence of novel motifs in large numbers of effectors of rust fungi with cell death suppression features. HighlightsO_LISecretome analysis of various plant pathogens performed C_LIO_LIA prioritization list for candidate effectors designed C_LIO_LIA novel WAxR motif was discovered in rust fungal effector proteins C_LIO_LITwo WAxR candidate effectors were functionally validated C_LI

microbiology↗

Horizontal transfer of a conserved npc-2 like effector gene in rust fungi that suppresses cell death in plants

ML/MD-2 is a conserved lipid/sterol-binding protein family having a role in sterol transfer and innate immunity in lower and higher eukaryotes. Here we report a genome-wide survey of this family, identifying 84 genes in 25 fungal and five oomycetes plant pathogen, having a different nutrition mode. All the fungal species were found to have varied numbers of family members, a distinctively substantial expansion of the ML gene family was observed in Rhizophagus irregularis (RI) with 33 genes. Our analysis also showed that NPC2 like proteins, a subfamily of ML domain superfamily, were not only restricted to animals and insect species but also present in plant fungal pathogens, including members of Clavicipitaceae, Pucciniacease, and Tremellaceae family. The phylogenetic analysis showed that these NPC2 like fungal proteins are more closely related to animals/insects than other fungal species. The molecular docking studies of these proteins with cholesterol and other derivatives indicate lipid-binding functional conservation across the animal and fungi kingdom. Further, the full length CDS of one of the npc2 like genes from Puccinia triticina (Pt5643) was PCR amplified and further characterized using various studies such as qRT-PCR, expression in onion epidermal cells, Nicotiana benthamiana for subcellular localization studies, yeast functional complementation, and expression studies. The mRNA abundance of Pt5643 was observed to be increased along with the infection progression and exhibits the highest expression at 5thday post-infection (dpi), suggesting its important role in the P. triticina infection cycle in wheat. The fluorescent confocal microscopy of transiently expressed YFP tagged Pt5643 in onion epidermal cells and N. benthamiana shows its location in cytoplasm and nucleus, indicating its involvement in the manipulation of host genes. The functional complementation of Pt5643 in npc2 mutant yeast showed its functional similarity to the eukaryotic npc2 gene. Further, the overexpression of Pt5643 also suppressed the BAX and H2O2 induced program cell death in N. benthamiana and yeast, respectively thus proving to be a novel horizontally transferred effector in rust fungal pathogens. Altogether the present study reports the novel function of fungal NPC2 like proteins playing a crucial role in host defense manipulation possibly through lipid binding/transport similar to animals.

microbiology↗

Pairwise Relative Distance (PRED) is an intuitive and robust metric for assessing vector similarity and class separability

Scientific studies often require assessment of similarity between ordered sets of values. Each set, containing one value for every dimension or class of data, can be conveniently represented as a vector. The commonly used metrics for vector similarity include angle-based metrics, such as cosine similarity or Pearson correlation, which compare the relative patterns of values, and distance-based metrics, such as the Euclidean distance, which compare the magnitudes of values. Here we evaluate a newly proposed metric, pairwise relative distance (PRED), which considers both relative patterns and magnitudes to provide a single measure of vector similarity. PRED essentially reveals whether the vectors are so similar that their values across the classes are separable. By comparing PRED to other common metrics in a variety of applications, we show that PRED provides a stable chance level irrespective of the number of classes, is invariant to global translation and scaling operations on data, has high dynamic range and low variability in handling noisy data, and can handle multi-dimensional data, as in the case of vectors containing temporal or population responses for each class. We also found that PRED can be adapted to function as a reliable metric of class separability even for datasets that lack the vector structure and simply contain multiple values for each class.

neuroscience↗

Comparable neutralization of SARS-CoV-2 Delta AY.1 and Delta in individuals sera vaccinated with BBV152

The recent emergence of the SARS-CoV-2 Variant of Concern, B.1.617.2 (Delta) variant and its high transmissibility has led to the second wave in India. BBV152, a whole-virion inactivated SARS-CoV-2 vaccine used for mass immunization in India, showed a 65.2% protection against the Delta variant in a double-blind, randomized, multicentre, phase 3 clinical trial. Subsequently, Delta has been further mutated to Delta AY.1, AY.2, and AY.3. Of these, AY.1 variant was first detected in India in April 2021 and subsequently from twenty other countries as well. Here, we have evaluated the IgG antibody titer and neutralizing potential of sera of COVID-19 naive individuals full doses of BBV152 vaccine, COVID-19 recovered cases with full dose vaccines and breakthrough cases post-immunization BBV152 vaccines against Delta, Delta AY.1 and B.1.617.3. A reduction in neutralizing activity was observed with the COVID-19 naive individuals full vaccinated (1.3, 1.5, 1.9-fold), COVID-19 recovered cases with full BBV152 immunization (2.5, 3.5, 3.8-fold) and breakthrough cases post-immunization (1.9, 2.8, 3.5-fold) against Delta, Delta AY.1 and B.1.617.3 respectively compared to B.1 variant. A minor reduction was observed in the neutralizing antibody titer in COVID-19 recovered cases full BBV152 vaccinated and post immunized infected cases compared to COVID-19 naive vaccinated individuals. However, with the observed high titers, the sera of individuals belonging to all the aforementioned groups they would still neutralize the Delta, Delta AY.1 and B.1.617.3 variants effectively.

molecular biology↗

SARS-CoV-2 Delta variant pathogenesis and host response in Syrian hamsters

B.1.617 lineage is becoming a dominant SARS-CoV-2 lineage worldwide and was the dominant lineage reported in second COVID-19 wave in India, which necessitated studying the properties of the variant. We evaluated the pathogenicity and virus shedding of B.1.617.2 (Delta) and B.1.617.3 lineage of SARS-CoV-2 and compared with that of B.1, an early virus isolate with D614G mutation in Syrian hamster model. Viral load, antibody response and lung disease were studied. No significant difference in the virus shedding pattern was observed among these variants studied. A significantly high SARS-CoV-2 sub genomic RNA could be detected in the respiratory tract of hamsters infected with Delta variant for 14 days. Delta variant induced lung disease of moderate severity in 40% of infected animals. The neutralizing capability of the B.1, Delta and B.1.617.3 variant infected animals were found significantly lower with the B.1.351 (Beta variant). The findings of the study support the attributed disease severity and the increased transmission potential of the Delta variant.

molecular biology↗

Neutralization of Delta variant with sera of Covishield vaccinees and COVID-19 recovered vaccinated individuals

The recent emergence of B.1.617 lineage has created grave public health problem in India. The lineage further mutated to generate sub-lineages B.1.617.1 (Kappa), B.1.617.2 (Delta), B.1.617.3. Apparently, the Delta variant has slowly dominated the other variants including B.1.617.1 (Kappa), B.1.617.2 (Delta), B.1.617.3. With this, World Health Organization has described this sub-lineage as variant of concern. The high transmissibility associated with Delta variant has led to second wave of pandemic in India which affected millions of people. Besides this, variant of concerns has been reported to show lower neutralization to several approved vaccines. This has led to breakthrough infections after completion of vaccination regimen. There is limited information available on the duration of protective immune response post-infection, vaccination or breakthrough infection with SARS-CoV-2. In this study, we have evaluated immune response in sera of the Covishield vaccinated individuals belonging to category: I. one dose vaccinated, II. two doses vaccinated, III. COVID-19 recovered plus one dose vaccinated, IV. COVID-19 recovered plus two doses vaccinated and V. breakthrough COVID-19 cases. The findings of the study demonstrated that the breakthrough cases and the COVID-19 recovered individuals with one or two dose of vaccine had relatively higher protection against Delta variant in comparison to the participants who were administered either one or two doses of Covishield. Prior vaccination results in less severe disease against subsequent infection provide evidence that both humoral and cellular immune response play an important role in protection.

microbiology↗

Neutralization against B.1.351 and B.1.617.2 with sera of COVID-19 recovered cases and vaccinees of BBV152

Recently, multiple SARS-CoV-2 variants have been detected across the globe. The recent emergence of B.1.617 lineage has created serious public health problem in India. The high transmissibility was observed with this lineage which has led to daily increase in the number of SARS-CoV-2 infections. Apparently, the sub-lineage B.1.617.2 has slowly dominated the other variants including B1617.1, B.617.3 and B.1.1.7. With this, World Health Organization has described B.1.617.2 as variant of concern. Besides this, variant of concern B.1.351 has been also reported from India, known to showreducedefficacyfor many approved vaccines. With the increasing threat of the SARS-CoV-2 variants, it is imperative to assess the efficacy of the currently available vaccines against these variants. Here, we have evaluated the neutralization potential of sera collected from COVID-19 recovered cases (n=20) and vaccinees with two doses of BBV152 (n=17) against B.1.351 and B.1.617.2 compared to the prototype B.1 (D614G) variant.The finding of the study demonstrated a reduction in neutralization titers with sera of COVID-19 recovered cases(3.3-fold and 4.6-fold) and BBV152 vaccinees (3. 0 and 2.7 fold) against B.1.351 and B.1.617.2 respectively.Although, there is reduction in neutralization titer, the whole-virion inactivated SARS-CoV-2 vaccine (BBV152) demonstrates protective response against VOC B.1351 and B.1.617.2.

microbiology↗

Isolation of SARS-CoV-2 B.1.1.28.2 P2 variant and pathogenicity comparison with D614G variant in hamster model

BackgroundConsidering the potential threat from emerging SARS-CoV-2 variants and the rising COVID-19 cases, SARS-CoV-2 genomic surveillance is ongoing in India. We report herewith the isolation of the P.2 variant (B.1.1.28.2) from international travelers and further its pathogenicity evaluation and comparison with D614G variant (B.1) in hamster model. MethodsVirus isolation was performed in Vero CCL81 cells and genomic characterization by next generation sequencing. The pathogenicity of the isolate was assessed in Syrian hamster model and compared with B.1 variant. ResultsB.1.1.28.2 variant was isolated from nasal/throat swabs of international travelers returned to India from United Kingdom and Brazil. The B.1.1.28.2 variant induced body weight loss, viral replication in the respiratory tract, lung lesions and caused severe lung pathology in infected Syrian hamster model in comparison, with B.1 variant infected hamsters. The sera from B.1.1.28.2 infected hamsters efficiently neutralized the D614G variant virus whereas 6-fold reduction in the neutralization was seen in case of D614G variant infected hamsters sera with the B.1.1.28.2 variant. ConclusionsB.1.1.28.2 lineage variant could be successfully isolated and characterization could be performed. Pathogenicity of the isolate was demonstrated in Syrian hamster model and in comparison, with B.1 variant was found more pathogenic. The findings of increased disease severity and neutralization reduction is of great concern and point towards the need for screening the vaccines for efficacy.

microbiology↗

Isolation and characterization of SARS-CoV-2 VOC, 20H/501Y.V2, from UAE travelers

Multiple SARS-CoV-2 variants have been emerged and created serious public health in the affected countries. The variant of Concern associated with high transmissibility, disease severity and escape mutations is threat to vaccination program across the globe. Travel has been important factor in spread of SARS-CoV-2 variants worldwide. India has also witnessed the dreadful effect of these SARS-CoV-2 variants. Here, we report the Isolation and characterization of SARS-CoV-2 VOC, 20H/501Y.V2 (B.1.351), from UAE travelers to India. The virus isolate would be useful to determine the efficacy of the currently available vaccines in India.

microbiology↗

Neutralization potential of Covishield vaccinated individuals against B.1.617.1

Covishield comprises the larger proportion in the vaccination program in India. Hence, it is of utmost importance to understand neutralizing capability of vaccine against the B.1.617.1 variant which is considered to responsible for surge of the cases in India. The neutralizing-antibody (NAb) titer against B.1.167.1 and prototype B.1 variant (D614G) was determined of the vaccine sera (4 weeks after second dose) of COVID-19 naive subjects (n=43) and COVID-19 recovered subjects (n=18). The results demonstrated that sera of COVID-19 recovered subjects (n=18) who received two doses of Covishield have higher NAb response compared to the COVID-19 naive with a significant difference (p<0.0001) in NAb titer against B.1 and B.1.617.1 In-spite of reduction in the neutralizing titer against B.1.617.1 variant; Covishield vaccine-induced antibodies are likely to be protective to limit the severity and mortality of the disease in the vaccinated individuals.

immunology↗

SARS CoV-2 variant B.1.617.1 is highly pathogenic in hamsters than B.1 variant

BackgroundThe recent emergence of new SARS-CoV-2 lineage B.1.617 in India has been associated with a surge in the number of daily infections. This variant has combination of specific mutations L452R, E484Q and P681R reported to possibly enhance the transmissibility with likelihood of escaping the immunity. We investigated the viral load and pathogenic potential of B.1.617.1 in Syrian golden hamsters. MethodsTwo groups of Syrian golden hamsters (9 each) were inoculated intranasally with SARS CoV-2 isolates, B.1 (D614G) and B.1.617.1 respectively. The animals were monitored daily for the clinical signs and body weight. The necropsy of three hamsters each was performed on 3, 5- and 7-days post-infection (DPI). Throat swab (TS), nasal wash (NW) and organ samples (lungs, nasal turbinate, trachea) were collected and screened using SARS-CoV-2 specific Real-time RT-PCR. ResultsThe hamsters infected with B.1.617.1 demonstrated increased body weight loss compared to B.1 variant. The highest viral load was observed in nasal turbinate and lung specimens of animals infected with B.1.167.1 on 3 DPI. Neutralizing antibody (NAb) and IgG response in hamsters of both the groups were observed from 5 and 7 DPI respectively. However, higher neutralizing antibody titers were observed against B.1.167.1. Gross pathology showed pronounced lung lesions and hemorrhage with B.1.671 compared to B.1. ConclusionsB.1617.1 and B.1 variant varied greatly in their infectiousness, pathogenesis in hamster model. This study demonstrates higher pathogenicity in hamsters evident with reduced body weight, higher viral load in lungs and pronounced lung lesions as compared to B.1 variant. SummaryB.1.617.1 is the new SARS-CoV-2 lineage that emerged in India. Maximal body weight loss and higher viral load in hamsters infected with B.1.617.1. It caused pronounced lung lesions in hamsters compared to B.1 variant which demonstrates the pathogenic potential of B.1.617.1.

microbiology↗