Browsing by Author "Jagat Kumar Roy"

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A forward genetic approach to mapping a P-Element second site mutation identifies DCP2 as a novel tumor suppressor in drosophila melanogaster
(Genetics Society of America, 2020) Rakesh Mishra; Rohit Kunar; Lolitika Mandal; Debasmita Pankaj Alone; Shanti Chandrasekharan; Anand Krishna Tiwari; Madhu Gwaldas Tapadia; Ashim Mukherjee; Jagat Kumar Roy
The use of transposons to create mutations has been the cornerstone of Drosophila genetics in the past few decades. Second-site mutations caused by transpositions are often devoid of transposons and thereby affect subsequent analyses. In a P-element mutagenesis screen, a second site mutation was identified on chromosome 3, wherein the homozygous mutants exhibit classic hallmarks of tumor suppressor mutants, including brain tumor and lethality; hence the mutant line was initially named as lethal (3) tumorous brain [l(3)tb]. Classical genetic approaches relying on meiotic recombination and subsequent complementation with chromosomal deletions and gene mutations mapped the mutation to CG6169, the mRNA decapping protein 2 (DCP2), on the left arm of the third chromosome (3L). Thus the mutation was renamed as DCP2l(3)tb. Fine mapping of the mutation further identified the presence of a Gypsy-LTR like sequence in the 59UTR coding region of DCP2, along with the expansion of the adjacent upstream intergenic AT-rich sequence. The mutant phenotypes are rescued by the introduction of a functional copy of DCP2 in the mutant background, thereby establishing the causal role of the mutation and providing a genetic validation of the allelism. With the increasing repertoire of genes being associated with tumor biology, this is the first instance of mRNA decapping protein being implicated in Drosophila tumorigenesis. Our findings, therefore, imply a plausible role for the mRNA degradation pathway in tumorigenesis and identify DCP2 as a potential candidate for future explorations of cell cycle regulatory mechanisms. Copyright © 2020 Mishra et al.
A highly sensitive naphthaoxazole-based cell-permeable ratiometric chemodosimeter for hydrazine
(Royal Society of Chemistry, 2016) Shweta; Ajit Kumar; Neeraj; Sharad Kumar Asthana; Anand Prakash; Jagat Kumar Roy; Ida Tiwari; K.K. Upadhyay
The environmental toxicity, detonable characteristics and widespread usage of hydrazine in industrial activities, coupled with the fact that it is a leading candidate as a hydrogen reservoir, mean that selective methods for the detection of trace levels of hydrazine are much needed. We report herein a ratiometric chemodosimeter (P1) for the highly efficient detection of hydrazine at a lowest level of 1.79 × 10-9 M. The P1 probe was designed by the judicious anchoring of a naphthaoxazole skeleton to malononitrile. The same chemodosimeter also enables the bioimaging of hydrazine in live cells. The performance of P1 was tested in the form of test paper strips, as well as in the solid state for the identification of hydrazine vapours. The sensing mechanism was established through spectroscopic techniques and was further fortified through theoretical calculations using density functional theory. © 2016 The Royal Society of Chemistry.
A multifunctional V-shape bis-hydrazone: Characterization, supramolecular architechtures, AIEE, recognition of cations (Cu 2+ , Zn 2+ ) and anions (HPO 4 2- and CN-), mechanochromism, computational and cell imaging studies
(Elsevier B.V., 2018) Kamini Tripathi; Alok Kumar Singh; Avinash Kumar Sonkar; Anand Prakash; Jagat Kumar Roy; Lallan Mishra
A new bis-hydrazone (PYDS) obtained by the condensation of pyridine 2,6-di carbohydrazide with 4-diethylaminosalicylaldehyde in methanol, has been fully characterized using various physicochemical techniques, finally supported by its single crystal X-ray crystallography. X-ray analysis provides novel supramolecular architectures using π-π stacking and H-bonding interactions. It shows aggregation induced emission enhancement (AIEE) in DMF: H 2 O (50:50,v/v) and results the formation of nanoaggregates of 356 nm. These aggregates are characterized by SEM, TEM, AFM and DLS techniques. PYDS detects Cu 2+ and Zn 2+ ions in DMF: H 2 O (7:3, v/v) and displays a turn-on response in absorbance with a high degree of selectivity against common interfering cations. The Cu 2+ and Zn 2+ ions are also detected via chelation enhanced quenching (CHEQ) and chelation enhanced fluorescence (CHEF) processes respectively. DFT and TD-DFT calculations support the experimental results. PYDS enables the visualization of Cu 2+ and Zn 2+ in SiHa cell lines and it also quantify their detection in real water samples with a high precision and good accuracy. The PYDS-Zn 2+ and PYDS-Cu 2+ ensembles act as secondary sensors for HPO 4 2− and CN- anions respectively. The reversible changes in crystalline and amorphous structures of PYDS on applying a mechanical stress has been exploited in the construction of binary memory states. © 2018 Elsevier B.V.
A selective hydrolytic and restructuring approach through a Schiff base design on a coumarin platform for “turn-on” fluorogenic sensing of Zn 2+
(Royal Society of Chemistry, 2019) Abha Pandey; Sharad Kumar Asthana; Anand Prakash; Jagat Kumar Roy; Ida Tiwari; K.K. Upadhyay
A new Schiff base, CMD, designed based on a coumarin platform was synthesized and fully characterized through single crystal X-ray diffraction studies. CMD underwent selective Zn 2+ -triggered hydrolysis in ethanolic medium followed by restructuring of its fragments, resulting in a “turn-on” green fluorogenic response. This response was confirmed through various physico-chemical measurements along with single crystal X-ray diffraction studies. This selective hydrolytic fluorogenic event was exploited for the successful optical detection and live cell imaging of Zn 2+ in SiHa cells. The above restructured products were characterized as two new Schiff bases, viz.CM and NSA, of which NSA was highly fluorescent (green). Hence, the formation of this green fluorogenic product accounted for the above fluorogenic “turn-on” sensing of Zn 2+ with a sub-nanomolar detection limit. Spectroscopic evidence along with mass determinations indicated that the Zn-CMD ensemble took the form of CM-Zn-CM in solution, supporting our above proposal of hydrolysis and restructuring. However, the X-ray diffraction studies of the Zn-CMD ensemble further revealed it to consist of NSA and CM-Zn-CM′, where CM′ is yet another new Schiff base formed in situ during the process of developing single crystals. © The Royal Society of Chemistry.
A smart switchable module for the detection of multiple ions: Via turn-on dual-optical readout and their cell imaging studies
(Royal Society of Chemistry, 2016) Abhishek Rai; Alok Kumar Singh; Avinash Kumar Sonkar; Anand Prakash; Jagat Kumar Roy; Rajamani Nagarajan; Lallan Mishra
A module switchable as a function of multi-stimuli response has been designed. The module displays sequential logic gate-based detection of multiple ions (Fe3+, Hg2+, CN- and S2-) at ppm levels via a "turn on" signature which potentially meets real-world-challenges through a simple synthetic route, a fast response, water based-activity, naked-eye visualization, regenerative-action, high selectivity and multiple readout for precise analysis. Living cell imaging of Fe3+ and Hg2+ has also been carried out in HeLa cell lines. © 2016 The Royal Society of Chemistry.
An unusual phenotypic and genotypic expression in F2 generation following one stage zidovudine exposure during pregnancy and lactation-an experiment in mice
(Japanese Society of Toxicology, 2012) Chongtham Rajlakshmi; Jagat Kumar Roy; Amit Kumar Rai; Asima Bhattacharyya; Bajarang Lal Pandey
Zidovudine (3'-Azido-2', 3'-dideoxythymidine, AZT, ZDV) is routinely used as one of the component of antiretroviral therapy to prevent transmission of the HIV infection from mother to child. The drug, when given during pregnancy can give rise to myriad toxicities as reported in previous studies on human, animal and in-vitro experiments. The present study was an attempt to explore the Zidovudine teratogenesis in F1 and F2 generation of mice following initial maternal exposure to Zidovudine during pregnancy, through delivery and lactation. The F1 generation actually would have got the exposure during embryonic development and infant stages. Pregnant Swiss mice were treated orally with ZDV 50 mg/ kg/day or distilled water (control), from day eighth of gestation, through delivery and continued for first ten days of lactation. The F1 generation litters were raised and mated to produce F2 generation mice. An interesting phenotype of "healthy" and "sick" was noted in F2 generation but not in the F1 generation. In F2 generation 35% died on different postnatal day during 120 days of follow up period. Chromosomal study from bone marrow of F1 and F2 showed various chromosomal aberrations. Lipodystrophy and hepatotoxicity was observed in "sick" mice. The study generated a hypothesis of recessive mutation and concludes that Zidovudine is a transplacental genotoxic agent. The result of present study therefore suggests the need to study the effect of zidovudine in human subjects for a longer period of time to rule out similar genotoxic effect.
Bantam regulates the axonal geometry of Drosophila larval brain by modulating actin regulator enabled
(Springer Verlag, 2018) Animesh Banerjee; Jagat Kumar Roy
During development, axonogenesis, an integral part of neurogenesis, is based on well-concerted events comprising generation, rearrangement, migration, elongation, and adhesion of neurons. Actin, specifically the crosstalk between the guardians of actin polymerization, like enabled, chickadee, capping protein plays an essential role in crafting several events of axonogenesis. Recent evidences reflect multifaceted role of microRNA during axonogenesis. Here, we investigated the role of bantam miRNA, a well-established miRNA in Drosophila, in regulating the actin organization during brain development. Our immunofluorescence studies showed altered arrangement of neurons and actin filaments whereas both qPCR and western blot revealed elevated expression of enabled, one of the actin modulators in bantam mutant background. Collectively, our results clearly demonstrate that bantam plays an instrumental role in shaping the axon architecture regulating the actin geometry through its modulator enabled. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
BRN3A, a transcription factor, regulates the expression of genes involved in biological processes shaping the HPV induced cervical cancer
(Genetics Society of Korea, 2025) Anand Prakash; Yashvant Patel; Jagat Kumar Roy
Background: Cervical cancer is the fourth most common cancer worldwide in females. This occurs primarily due to the infection of high-risk Human Papilloma Virus (HPV), although in advanced stages it requires support from host cellular factors. BRN3A is one such host cellular factors, whose expression remains high in cervical cancers and upregulates tumorigenic HPV gene expression. The effect of BRN3A on HPV-mediated cervical cancer and the underlying mechanism remains obscure. Objective: To investigates the effect of BRN3A on cancer-promoting biological processes in HPV-positive uterine cervix cancer cells. Methods: We have altered the expression of BRN3A through over-expression (OE) and knock-down (KD) constructs in cervical cancer cell line, SiHa, and did transcriptome profiling through next-generation RNA-sequencing, validation through RT-PCR and BRN3A binding study with in silico promoter study and ChIP PCR methods. Results: This study revealed a substantial change in the expression of several genes associated with cancer-promoting biological processes including viral processes, immune response, cell-death, cell-proliferation, different signaling pathways, etc. Additionally, promoter analysis through in silico mode revealed that a total of 32.7% of genes possess BRN3A binding sites at their promoters. Physical interaction of BRN3A with IFITM1, OAS3, ISG15, BCL2L1 and HSP90AB1 genes was also confirmed. Conclusions: The present study identified molecular targets of BRN3A and provided new insight into the pathogenesis of cervical cancer. According to our knowledge, this is the first report on the effect on eukaryotic transcriptomes after over-expression and knocking down BRN3A. © The Author(s) under exclusive licence to The Genetics Society of Korea 2025.
Cancer cell metabolism and developmental homeodomain/POU domain transcription factors: A connecting link
(Elsevier Ireland Ltd, 2015) Biswa Pratim Das Purkayastha; Jagat Kumar Roy
The human race is afflicted with more than 100 types of cancer with diversified underlying genetic events. Still, altered metabolism (known as 'Warburg effect') and unrestrained cellular proliferation are precise traits of all cancers, being governed by the expression of genes. The obligatory energy for the proliferating neoplastic cells is endowed through the glycolytic pathway, albeit, lesser ATP is generated in this metabolic process. So, some perceptible cancer cell specific signalling is at the base of the transformed metabolism. Concurrently, the regulators of gene expression, transcription factors, have been observed to be one of the driving forces for tumourigenesis through transcriptional activation of genes involved not only in proliferation, growth and survival signalling, but also in glycolysis. This may be exemplified by the extensively studied metabolic functions of the transcriptional regulator, hypoxia inducible factor 1 (HIF1), which transactivates genes of the major enzymes of glycolysis. Preliminary investigation of a vital group of transcription factors, homeodomain transcription factors, revealed association with the process of development of an organism. The homeodomain transcription factors are, however, also found to be involved in the tumourigenesis process, with little or no information on their involvement in cancer cell metabolism. So, this is a review of the existing knowledge on homeodomain transcription factor/s for deciphering their involvement in neoplastic metabolism and it emerges that homeodomain transcription factors influence the transformed metabolic pathway in a circuitous manner. © 2014 Elsevier Ireland Ltd.
Classification of clinical isolates of klebsiella pneumoniae based on their in vitro biofilm forming capabilities and elucidation of the biofilm matrix chemistry with special reference to the protein content
(Frontiers Media S.A., 2019) Ashish Kumar Singh; Shivangi Yadav; Brijesh Singh Chauhan; Nabarun Nandy; Rajan Singh; Kaushik Neogi; Jagat Kumar Roy; Saripella Srikrishna; Rakesh Kumar Singh; Pradyot Prakash
Klebsiella pneumoniae is a human pathogen, capable of forming biofilms on abiotic and biotic surfaces. The limitations of the therapeutic options against Klebsiella pneumoniae is actually due to its innate capabilities to form biofilm and harboring determinants of multidrug resistance. We utilized a newer approach for classification of biofilm producing Klebsiella pneumoniae isolates and subsequently we evaluated the chemistry of its slime, more accurately its biofilm. We extracted and determined the amount of polysaccharides and proteins from representative bacterial biofilms. The spatial distribution of sugars and proteins were then investigated in the biofilm matrix using confocal laser scanning microscopy (CLSM). Thereafter, the extracted matrix components were subjected to sophisticated analysis incorporating Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, one-dimensional gel-based electrophoresis (SDS-PAGE), high performance liquid chromatography (HPLC), and MALDI MS/MS analysis. Besides, the quantification of its total proteins, total sugars, uronates, total acetyl content was also done. Results suggest sugars are not the only/major constituent of its biofilms. The proteins were harvested and subjected to SDS-PAGE which revealed various common and unique protein bands. The common band was excised and analyzed by HPLC. MALDI MS/MS results of this common protein band indicated the presence of different proteins within the biofilm. The 55 different proteins were identified including both cytosolic and membrane proteins. About 22 proteins were related to protein synthesis and processing while 15 proteins were identified related to virulence. Similarly, proteins related to energy and metabolism were 8 and those related to capsule and cell wall synthesis were 4. These results will improve our understanding of Klebsiella biofilm composition and will further help us design better strategies for controlling its biofilm such as techniques focused on weakening/targeting certain portions of the slime which is the most common building block of the biofilm matrix. Copyright © 2019 Singh, Yadav, Chauhan, Nandy, Singh, Neogi, Roy, Srikrishna, Singh and Prakash. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Decoding the epigenetic mechanism of mammalian sex determination
(Elsevier Inc., 2024) Cash Kumar; Jagat Kumar Roy
Sex determination embodies a dynamic and intricate developmental process wielding significant influence over the destiny of bipotential gonads, steering them towards male or female gonads. Gonadal differentiation and the postnatal manifestation of the gonadal phenotype involve a sophisticated interplay of transcription factors such as SOX9 and FOXL2. Central to this interplay are chromatin modifiers regulating the mutual antagonism during this interplay. In this review, the key findings and knowledge gaps in DNA methylation, histone modification, and non-coding RNA-mediated control throughout mammalian gonadal development are covered. Furthermore, it explores the role of the developing brain in playing a pivotal role in the initiation of gonadogenesis and the subsequent involvement of gonadal hormone/hormone receptor in fine-tuning sexual differentiation. Based on promising facts, the role of the developing brain through the hypothalamic pituitary gonadal axis is explained and suggested as a novel hypothesis. The article also discusses the potential impact of ecological factors on the human epigenome in relation to sex determination and trans-generational epigenetics in uncovering novel genes and mechanisms involved in sex determination and gonadal differentiation. We have subtly emphasized the disruptions in epigenetic regulations contributing to sexual disorders, which further allows us to raise certain questions, decipher approaches for handling these questions and setting up the direction of future research. © Elsevier Inc.
Developmental delay in DCP2l(3)tb of Drosophila melanogaster is due to disruption in the regulation of ecdysone signaling
(Elsevier Inc., 2025) Govind R. Chaudhary; Vaishali Yadav; Jagat Kumar Roy
The balance between mRNA synthesis and degradation plays an important role in gene regulation, their perturbation can lead to deleterious consequences to the cell. In eukaryotes, mRNA is degraded by a decapping protein-2 (DCP2). A hypomorph mutant allele of DCP2, DCP2 l(3)tb , identified in our lab, shows delayed moulting, pupariation and absolute lethality in pupal stages. In Drosophila , moulting and pupariation are primarily regulated by ecdysone which is modulated by a few regulators synthesized by the larval brain, some are stimulatory such as Prothoracicotropic hormone (PTTH) and Drosophila insulin-like peptides (Dilps); whereas some are inhibitory, such as Lgr3-expressing neurons. We aimed to investigate the cause of the delay in moulting and pupariation in DCP2 l(3)tb homozygous mutants. Through our RNA Seq data, we found downregulated expression of brain-derived neuropeptides such as PTTH and Dilps which were further confirmed and validated through qRT-PCR and semiquantitative PCR. Furthermore, we assessed the mRNA level of Lgr3 which was found to be upregulated in the larval CNS of DCP2 l(3)tb homozygotes suggesting insufficient production of stimulatory modulators. Further, providing 20H-ecdysone exogenously through diet, curtailed the extended larval life. We propose that the larval CNS of DCP2 l(3)tb homozygotes produces insufficient brain-derived neuropeptides to stimulate the prothoracic gland to synthesize the ecdysone required for moulting and metamorphosis. © © 2025. Published by Elsevier Inc.
Developmental expression of Rab11, a small GTP-binding protein in Drosophila epithelia
(2009) Satish Sasikumar; Jagat Kumar Roy
Intracellular membrane trafficking regulates a wide variety of developmental processes, including cell and tissue morphogenesis. Here we report developmental expression of Drosophila Rab11, a small GTP-binding protein, required for both endocytic recycling and exocytosis. Rab11 is expressed in the epithelial cell types of diverse lineages at all developmental stages, beginning from the cellular blastoderm in early embryos to adult primordia and adult tissues, like the columnar epithelia lining male ejaculatory bulb. A robust expression of Rab11 is seen both in the amnioserosa and in the lateral epidermis during embryonic dorsal closure, a morphogenetic event that involves spreading and fusion of the contra-lateral sides of epidermis. Rab11 mutant embryos fail to display the characteristic morphological changes in these two epithelial tissues during dorsal closure, providing a strong basis to dissect the role of Rab11 in coordinated epithelial sheet movements. © 2008 Wiley-Liss, Inc.
Dicer-1 regulates proliferative potential of Drosophila larval neural stem cells through bantam miRNA based down-regulation of the G1/S inhibitor Dacapo
(Academic Press Inc., 2017) Animesh Banerjee; Jagat Kumar Roy
The present work elucidates the role of miRNA in cell cycle regulation during brain development in Drosophila. Here we report that lineage specific depletion of dicer-1, a classically acknowledged miRNA biogenesis protein in neuroblasts leads to a reduction in their numbers and size in the third instar larval central brain. These brains also showed lower number of mitotically active cells and when homozygous mitotic clones were generated in an otherwise heterozygous dicer-1 mutant background via MARCM technique, they showed reduced number of progeny cells in individual clones, substantiating the adverse effect of the loss of dicer-1 on the proliferative potential of neuroblasts. bantam miRNA, which has been classically reported to be involved in tissue growth was found to express in neuroblasts and undergo reduced expression in Dicer-1 depleted background in the third instar larval brain. Reduction in the number and proliferative potential of neuroblasts in bantam mutant background implies a pivotal role played by bantam miRNA in maintenance of neuroblast number. Since, in both Dicer-1 and bantam depleted genetic backgrounds, Dacapo, an inhibitor of cyclin E-Cdk complex, was found to have elevated expression, we put forward a molecular mechanism involving bantam-Dacapo-Cyclin E/Cdk complex that regulates the G1-S phase transition of Drosophila neuroblasts. © 2017 Elsevier Inc.
Downregulated Expression of WWOX in Cervical Carcinoma: A Case-Control Study
(Babol University of Medical Sciences, 2020) Shikha Srivastava; Uday Pratap Shah; Arti Divya; Sadhana Gupta; Indu Singh; Jagat Kumar Roy
Integration of human papilloma virus (HPV) in human genome is a random event, and fragile sites are one of the most susceptible sites for viral integrations. WWOX (WW-domain containing oxidoreductase) gene harbours the second most common fragile site, FRA16D, and can be an important candidate for HPV integration and cervical carcinogenesis. Our aim was to evaluate the potential role of WWOX in cervical carcinogenesis. Presence of HPV and its genotype was detected by PCR in normal cervix tissues and human cervical carcinoma. The expression of WWOX transcript and its protein was examined by RT-PCR, RNA in situ hybridization, and immunoblotting. Southern blotting and sequencing were used to determine the alternative transcripts of WWOX. Statistical analysis were performed by Mann Whitney U-test, Pearson correlation coefficient test at significance level of P value < 0.05. Prevalence of HPV was observed in cervicitis (40%), cervical intraepithelial neoplasia patients (50%), and invasive cervical carcinoma patients (89.6%). Clinicopathological findings suggested a correlation of reduced level of WWOX protein and progression of cervical carcinoma deciphering its role in tumorigenesis. Furthermore, we observed aberrant WWOX transcript having deleted exon 6-8 region in invasive cervical cancer tissues as well as normal cervix samples. More than 60% of cervical carcinoma samples showed reduced protein level with an increase in wild type transcript level suggesting the involvement of a negative regulator, pAck1 (activated Cdc42-associated kinase) which might ubiquitinate WWOX protein leading to its degradation. Also, nuclear retention of WWOX transcript in invasive cervical carcinoma tissues suggests its regulation at post-transcriptional level. Our findings suggest that WWOX acts as a tumor suppressor in cervical carcinoma and could act as a potential therapeutic target for the disease. © 2020, International Journal of Molecular and Cellular Medicine. All Rights Reserved.
Endosomal recycling protein Rab11 in Parkin and Pink1 signaling in Drosophila model of Parkinson's disease
(Elsevier Inc., 2022) Pooja Rai; Jagat Kumar Roy
Neurodegenerative diseases are progressive disorders of the nervous system primarily affecting the loss of neuronal cells present in the brain. Although most neurodegenerative cases are sporadic, some familial genes are found to be involved in the neurodegenerative diseases. The extensively studied parkin and pink1 gene products are known to be involved in the removal of damaged mitochondria via autophagy (mitophagy), a quality control process. If the function of any of these genes is somehow disrupted, accumulation of damaged mitochondria occurs in the forms of protein aggregates in the cytoplasm, leading to formation of the Lewy-bodies. Autophagy is an important catabolic process where the endosomal Rab proteins are seen to be involved. Rab11, an endosomal recycling protein, serves as an ATG9A carrier that helps in autophagosome formation and maturation. Earlier studies have reported that loss of Rab11 prevents the fusion of autophagosomes with the late endosomes hampering the autophagy pathway resulting in apoptosis of cells. In this study, we have emphasized on the importance and functional role of Rab11 in the molecular pathway of Parkin/Pink1 in Parkinson's disease. © 2022
Exploring the therapeutic potential of Rab11: A comprehensive study on its effectiveness in alleviating rotenone-induced molecular pathogenesis of Parkinson's disease in SH-SY5Y cells and its synergistic application with L-DOPA in Drosophila models
(Elsevier B.V., 2024) Pooja Rai; Sada Nand Pandey; Jagat Kumar Roy
Dysfunctional mitophagy contributes to Parkinson's disease (PD) by affecting dopamine-producing neurons. Mutations in parkin and pink1 genes, linked to familial PD, impede the removal of damaged mitochondria. Previous studies suggested Rab11's involvement in mitophagy alongside Parkin and Pink1. Additionally, mitochondria-endoplasmic reticulum contact sites (MERCS) regulate cellular functions, including mitochondrial quality control and calcium regulation. Our study explored whether activating mitophagy triggers the unfolded protein response and ER stress pathway in SH-SY5Y human cells. We induced a PD-like state by exposing undifferentiated SH-SY5Y cells to rotenone, an established PD-inducing agent. This led to reduced Rab11 and PERK- expression while increasing ATP5a, a mitochondrial marker, when Rab11 was overexpressed. Our findings suggest that enhancing endosomal trafficking can mitigate ER stress by regulating mitochondria, rescuing cells from apoptosis. Furthermore, we assessed the therapeutic potential of Rab11, both alone and in combination with L-Dopa, in a Drosophila PD model. In summary, our research underscores the role of mitophagy dysfunction in PD pathogenesis, highlighting Rab11's importance in alleviating ER stress and preserving mitochondrial function. It also provides insights into potential PD management strategies, including the synergistic use of Rab11 and L-Dopa. © 2024
High prevalence of oncogenic HPV-16 in cervical smears of asymptomatic women of eastern Uttar Pradesh, India: A population-based study
(2012) Shikha Srivastava; Sadhana Gupta; Jagat Kumar Roy
In developing countries like India, occurrence of Human papillomavirus (HPV) in cervical cancer as well as in the asymptomatic population was observed to be very high. Studies on HPV prevalence have been conducted in different parts of the country but no data were available from the eastern region of Uttar Pradesh (UP). The present study aimed to determine the status of HPV prevalence and its association with different socio-demographic factors in this population. Prevalence of HPV was investigated in a total of 2424 cervical scrape samples of asymptomatic women. Primer sets from L1 consensus region of viral genome were used to detect the presence of HPV, and the positive samples were genotyped by sequencing. Univariate binary logistic regression analysis was used to evaluate association of socio-demographic factors with HPV. 9.9% of the clinically asymptomatic women were found to be infected with HPV comprising 26 different genotypes. Among HPV-positive women, 80.8% showed single infection, while 15.4% harboured multiple infections. HPV-16 (63.7%) was the most prevalent, followed by HPV-31 (6.7%), HPV-6 (5.4%), HPV-81 (4.6%) and HPV-33 (4.2%). Significant association of HPV with non-vegetarian diet (P<0.05) and rural residential areas (P<0.01) were observed. High prevalence of HPV-16 in asymptomatic women of this population, a frequency comparable to invasive cervical cancers, highlights an urgent need for a therapeutic HPV vaccine covering HPV-16 and other high-risk types to provide protection against the disease. © 2012 Indian Academy of Sciences.
Molecular analysis of oncogenicity of the transcription factor, BRN3A, in cervical cancer cells
(2011) Biswa Pratim Das Purkayastha; Jagat Kumar Roy
Objective: The host cellular transcription factor, BRN3A, has been observed to play a vital role in cancer of the uterine cervix. BRN3A possesses multipartite functions, which include transcription of the genes of the high-risk HPVs and mediation of cellular changes in the host. In this study, we made an effort to decipher the regulation of BRN3A in cervical cancer cells by studying its interaction with different components of the cell. Methods: In cervical cancer cells, the endogenous HIPK2 was induced through cisplatin treatment, and then, its subsequent effect on BRN3A was primarily investigated through co-immunostaining and western blotting as HIPK2 has been observed to act as a co-repressor of Brn3a. The physical interaction of the two proteins was analyzed through co-immunoprecipitation. We resorted to chromatin immunoprecipitation in order to testify the autoregulatory pathway of BRN3A in cervical cancer cells. Interaction of BRN3A with cellular components, p73 and active form of JNK, was also studied through co-immunostaining. Results: We observed that BRN3A is independent of the regulative activity of HIPK2 and undergoes positive autoregulation in cervical cancer cells. Interestingly, during the study, it was revealed that BRN3A is unaffected by the treatment of cisplatin. Interaction of BRN3A with p73 and phosphorylated JNK in cervical cancer cells, observed in the present study, would help in understanding the molecular mechanism directed by BRN3A. Conclusions: BRN3A possesses anti-apoptotic property, and considering the above results, it may be regarded as the key component in promoting tumorigenic growth in the uterine cervical cells. © 2011 Springer-Verlag.
Novel Variant Identified in the Enhancer Region of Host Transcription Factor, BRN3A, is a Significant Risk Factor for HPV-Induced Uterine Cervix Cancer
(Babol University of Medical Sciences, 2022) Anand Prakash; Biswa Pratim Das Purkayastha; Shikha Srivastava; Sunanda Chaturvedi; Akhtar Ali; Dau Dayal Aggarwal; Jagat Kumar Roy
Among the HPV-mediated cervical cancers, cellular factor BRN3A has gained considerable attention due to its role in promoting an anti-apoptotic cellular environment and in facilitating epitheliotropic transformations of the host. The majority of previous studies looked at BRN3A's molecular characteristics; however, the possibility of genetic variations in BRN3A's autoregulatory region in relation to cervical cancer risk has been underestimated until now. In a retrospective study in the Eastern UP population, India, we detected genetic variations in the cisregulatory proximal enhancer region located around 5.6 kb upstream of transcription start site of BRN3A. Our analysis of PCR and DNA sequencing confirmed this novel SNP (BRN3A g.60163379A>G) within the auto-regulatory region of BRN3A. As compared to control subjects, cancer cases exhibited a 1.32-fold higher allele frequency (χ2 = 6.315, p = 0.012). In homozygous (GG) but not in heterozygous conditions, odds ratio (OR) analysis suggests a significant association of cancer risk with the SNP (OR = 2.60, p ≤ 0.004). We further confirmed using the functional analysis that this SNP increased the luciferase gene activity in HPV-positive cervical cancer SiHa cells that were exposed to progesterone. As a result of the association of polymorphisms in a noncoding region of an oncogene with increased cancer risks, we are suggesting that this genetic variation in non-coding region can be used in prediction, diagnosis, or predicting the progression of the disease. © The Author(s).