Biology subjects

Maiti, T. K.

Publications and source records attributed to Maiti, T. K..

13 recordsLinked to original sources

bioRxiv2026

Gestational exposure of bisphenol-A limits decidual ECM organization via S100a10-Annexin A2 axis in murine placenta

Environmental exposure to endocrine disrupting chemicals, like bisphenol-A (BPA), can impart detrimental effects on developing feto-placental unit, during pregnancy. Placenta remains a central player maintaining this feto-placental homeostasis for sustenance of a healthy pregnancy. Thus, the bisphenol-A mediated endocrine disruption affects the healthy functioning of placenta by altering key processes, such as tissue remodelling, angiogenesis, and metabolism. However, the underlying mechanism of BPA-altered ECM remodelling remains elusive. Therefore, in this study we investigated the BPA mediated changes in placental tissue remodelling using a bisphenol-A exposed murine model during pregnancy. The results reveal that, the phenotypic changes in feto-placental interface correlates with perturbed placental proteome in response to BPA. Further investigation highlights a S100a10-Annexin A2 axis mediated upregulation of tissue plasminogen activator (tPA), which drives altered extracellular matrix (ECM) degradation in placental decidua. This culminates into functional dysregulation in feto-placental axis, leading to reduced size of fetus and placenta. Therefore, this study provides novel insights of a S100a10-Annexin A2 axis associated mechanism for alteration of ECM remodelling in placental decidua due to BPA exposure, which may lead to toxicity related adverse pregnancy outcome.

developmental biology↗

bioRxiv2026

Bisphenol-A mediated ubiquitinome alteration triggers PPAR-alpha ubiquitination, affecting trophoblast cell migration

Pregnant women are frequently exposed to various endocrine-disrupting chemicals (EDCs), such as bisphenol A (BPA), causing harm to both the developing placenta and fetus. BPA can promote placental dysfunction by altering key cellular processes such as differentiation, invasion, and migration in trophoblast cells. These cellular processes are also tightly managed by the ubiquitin proteasomal system via maintenance of the ubiquitinated protein pool. However, the BPA-mediated dysregulation of this ubiquitin proteasomal homeostasis is poorly understood. Therefore, we identified 19 deubiquitinases (DUBs) and a dynamic ubiquitinome profile of extravillous trophoblast cells (HTR8/SVneo), which reduced trophoblast cell migration post-BPA exposure. Further investigation using an integrated substrate-ligase-deubiquitinase network shows that BPA binding to PPAR-alpha or indirect regulation of its E3 Ligase MuRF1 and DUB USP5 via BPA resulted in hyper-ubiquitination of PPAR-alpha, triggering its nuclear localization. In the nucleus, the ubiquitinated PPAR-alpha can deregulate its migration-associated target gene expression, causing a reduction in the migration of HTR8/SVneo cells. This physiological alteration of extravillous trophoblast cells (EVTs) through BPA can disrupt placental homeostasis. Hence, we assumed that BPA-induced cellular alteration in EVTs can promote placental defects, which might contribute to adverse pregnancy outcomes.

biochemistry↗

bioRxiv2026

Ferroptosis links α-synuclein pathology across brain and skeletal muscle in Parkinsons disease

Parkinsons disease (PD) is increasingly recognized as a multisystem disorder, yet the mechanisms linking neurodegeneration with muscle dysfunction remain largely unknown. In this study, using an A53T -synuclein (Syn) transgenic mouse model, we demonstrate coordinated pathological changes across the brain-muscle organs characterized by systemic inflammation, iron accumulation, oxidative stress, and ferroptosis-associated lipid peroxidation. Our quantitative proteomics data revealed dysregulated iron metabolism and ferroptosis in the brain and skeletal muscle. Biochemical validation confirmed increased expression of Transferrin receptor 1 (TFRC), elevated lipid peroxidation, and suppression of antioxidant defenses, including SLC7A11 and GPX4, indicating enhanced ferroptotic susceptibility. Cell-surface proteomics and biophysical assays further revealed that pathological Syn directly interacts with TFRC, promoting iron accumulation and ferroptosis-associated oxidative damage in neuronal and muscle cells. Together, our findings identify ferroptosis as a shared pathological mechanism across the brain and muscle, mediated by the Syn-TFRC interaction, thus linking neurodegeneration and peripheral muscle pathology in PD.

neuroscience↗

bioRxiv2026

Ribosome Processing Factor-2 Interacts with RPL10A to Regulate Selective Translation during Plant Immunity and Drought Stress

Processing of ribosomal RNA (rRNA) is essential for ribosome biogenesis, translation, plant development, and stress adaptation. Ribosome processing factor-2 (RPF2), which plays a role in the later stages of rRNA maturation, interacts with ribosomal protein L10A (RPL10A). RPF2 overexpression in Arabidopsis and Nicotiana benthamiana showed enhanced plant growth and trichome development due to increased gibberellic acid (GA) levels. Conversely, RPF2-silenced and mutant plants had a dwarf phenotype, reduced stomatal apertures, and decreased glucosinolate accumulation. RPF2 silenced and mutant plants also showed compromised nonhost disease resistance, whereas RPF2 overexpression lines exhibited enhanced disease resistance to both host and nonhost pathogens. RPL10A and RPF2 overexpression lines were sensitive to abscisic acid (ABA) and tolerant to drought, which is attributed to their unique roles in translation regulation. Despite having larger stomatal apertures, RPF2 overexpression plants displayed low pathogen multiplication rates and reduced water loss, indicating independent resistance mechanisms associated with ribosomal functions in translation regulation. Although both RPL10A and RPF2 proteins interact with each other and are involved in translation regulation, proteomic analysis suggests that they regulate the translation of distinct sets of genes during pathogen or drought stress. These findings indicate that RPF2 and RPL10A play independent roles in the regulation of unique protein translation.

plant biology↗

bioRxiv2026

Integrated proteomic and phosphoproteomic profiling reveals mechanisms of Bisphenol-A induced placental toxicity

The global industrialization and rapid urbanization elevated the risk of toxic pollutant exposure, which affects human health specially during pregnancy. Pregnant mothers are daily exposed to bisphenol-A (BPA), which is a common plastic leachate and a prominent toxic pollutant present in our environment. BPA act as an endocrine disrupting chemical (EDCs) by altering feto-placental homeostasis. This persistent and potent exposure of BPA during gestation can trigger placental damage affecting trophoblast cell function and survival. BPA even disrupts specific signalling cascades by altering post translational protein phosphorylation. However, this BPA mediated dysregulation of signalling nodes in early trimester placenta is still unexplored. Therefore, this study investigates the global proteome changes in post-BPA exposed extravillous trophoblast (EVTs) cells, which revealed a BPA mediated dynamic regulation of phosphoproteome-signatures and their associated kinases. Further inspection showed that the altered phosphorylation of c-JUN (S63) and GSK3 (Y279) is associated with BPA toxicity in EVTs and placenta. This altered phosphorylation affects the cellular signalling downstream, imparting damage upon the growing feto-placental unit. This highlights an altered phosphorylation mediated mechanism of BPA toxicity in placenta which can cause an onset of adverse pregnancy outcome. Data are available via ProteomeXchange with the identifiers PXD074780.

biochemistry↗

bioRxiv2025

Synapse-related protein alterations and estradiol deficiency associate with early Parkinsonism in female A53T-α-synuclein transgenic mice fed on a high-fat diet

Substantial evidence highlights the detrimental impact of a fat-rich diet on cognitive and emotional behaviour. Epidemiological studies have linked the consumption of saturated fat with an increased risk of Parkinsons disease (PD), whereas a low-fat or ketogenic diet is reported to improve both motor and non-motor symptoms. Several animal model studies further support these associations. However, the impact of a high-fat diet (HFD) on sex-specific behavioural alterations and the underlying molecular mechanism in PD remains poorly studied. In the present study, we investigated the impact of HFD on PD progression in a sex-specific manner using the A53T transgenic mouse model of PD. Behavioural and pathophysiological analyses revealed a faster onset and progression of PD-like phenotype in female mice exposed to HFD compared with the male mice. Proteomics profiling of brain tissues demonstrated positive enrichment of immune system-related pathways in males, while females exhibited considerable downregulation of synapse-associated pathways under HFD conditions. The reduced estradiol level was identified as a potential factor contributing to synaptic dysfunction and the subsequent early onset of PD in female mice. These findings provide novel insights into the sex-specific consequences of HFD on PD pathogenesis and highlight the role of estrogen-linked synaptic vulnerability in mediating diet-induced PD onset.

neuroscience↗

bioRxiv2025

Uttroside B, a US FDA-designated Orphan drug, mitigates thedevelopment of hepatocellular carcinoma and its pulmonary metastasis via EGFR/ERK-mediated inhibition of SREBP-1 and STAT-3

Hepatocellular carcinoma (HCC) is a highly aggressive tumor with rapid propensity for extrahepatic metastasis, which critically limits the long-term clinical benefits of conventional chemotherapeutics and decreases the overall survival rate of patients. Our previous findings on the exceptional anti-HCC potential and pharmacological safety of uttroside B (Utt-B) have gained multiple international patents and the compound has been designated as an Orphan Drug against HCC by the US FDA. The current study substantiates the pharmacodynamics of Utt-B and is the first report to date on the anti-metastatic potential of the compound against HCC. Herein, we demonstrate the role of EGFR/ERK signaling axis and their downstream targets SREBP-1 and STAT-3, the key regulators of HCC development and the pulmonary metastasis, respectively, in orchestrating the anti-HCC and anti-metastatic potential of Utt-B. This is evidenced by the abrogation of the cytotoxic and pro-apoptotic effects of Utt-B upon pharmacological inhibition of this signaling axis. Orthotopic xenograft studies validated that Utt-B treatment restricted the development of tumors via the down-regulation of EGFR/ERK axis. Notably, Utt-B diminishes the migratory and invasive properties of liver cancer cells in vitro and impedes the pulmonary metastasis of HCC, in vivo. Taken together, the current findings attest to the exceptional therapeutic potential of Utt-B against primary and metastatic HCC and highlight its potential as a candidate drug to be evaluated in the clinics for the benefit of HCC patients having limited prognosis and therapeutic options.

cancer biology↗

bioRxiv2024

Arabidopsis AtGELP53 modulates polysaccharide acetylation and defense response through oligosaccharide-mediated signaling

O-acetylation is a crucial substitution found in hemicelluloses and pectin which are necessary for maintaining the flexibility and structural integrity of the cell. A balanced polysaccharide O-acetylation level is maintained by cell wall acetyl transferases and esterases present in different cell organelles. Specifically, the role of esterases in cell wall acetylation metabolism is less explored. Therefore, we investigated the role of AtGELP53 from the GELP family of esterases or lipases. Here, we show that AtGELP53 is localized in the plasma membrane. Analysis of AtGELP53 overexpressing independent transgenic lines revealed a decrease in xyloglucan acetylation, changes in other polysaccharide acetylation and alteration in cell wall composition. The series of elicitor-based, transcriptomic and proteomic analyses in AtGELP53 overexpressing lines suggested that oligosaccharide-mediated signalling activates the cell wall and defence-related genes primarily because of xyloglucan deacetylation. Furthermore, AtGELP53 overexpression plants showed resistance against Pseudomonas syringae and Ralstonia solanacearum through activation of elicitor-mediated defense response. Overall, our findings outline the role of AtGELP53 in polysaccharide acetylation, cell wall remodelling and defense through the activation of plant cell wall integrity.

plant biology↗

bioRxiv2022

Hepatitis C virus induces HuR relocalization by coordinating PKC-δ and AMPK- function

Host protein HuR translocation from nucleus to cytoplasm following infection is crucial for the life cycle of several RNA viruses including hepatitis C virus (HCV), a major causative agent of hepatocellular carcinoma. HuR assists the assembly of replication-complex on the viral-3'UTR, and its depletion hampers viral replication. Although cytoplasmic HuR is crucial for HCV replication, little is known about how the virus orchestrates the mobilization of HuR into the cytoplasm from the nucleus. We show that two viral proteins, NS3 and NS5A, act co-ordinately to alter the equilibrium of the nucleo-cytoplasmic movement of HuR. NS3 activates protein kinase C (PKC)-{delta}, which in-turn phosphorylates HuR on S318 residue, triggering its export to the cytoplasm. NS5A inactivates AMP-activated kinase (AMPK) resulting in diminished nuclear import of HuR through blockade of AMPK-mediated phosphorylation and acetylation of importin-1. Cytoplasmic retention or entry of HuR can be reversed by an AMPK activator or a PKC-{delta} inhibitor. Our findings suggest that efforts should be made to develop inhibitors of PKC-{delta} and AMPK, either separately or in combination, to inhibit HCV infection. Author summaryHepatitis C virus is a major human pathogen, which exploits cellular machinery for its propagation in liver cells. The cytoplasmic availability of cellular components is crucial for their direct influence on processes involving the viral RNA, which lacks any nuclear history. Our results establish the involvement of viral proteins, NS3 and NS5A in achieving increased cytoplasmic abundance of a host factor HuR, an RNA binding protein (RBP) critical for HCV replication. This is achieved via direct post-translational modification of HuR and indirect regulation of its nuclear carrier by coercing two host kinases, PKC-{delta} and AMPK-. RBPs are emerging as novel targetable candidates for gene regulation. Similar studies with other RBPs and targeting protein modifications, in place of whole protein knockdown, could usher in a revolutionary strategy to neutralize emerging RNA virus-based diseases, while preserving their cellular functions.

microbiology↗

bioRxiv2022

RNA-protein interactome at the Hepatitis E virus internal ribosome entry site

Multiple processes exist in a cell to ensure continuous production of essential proteins either through cap-dependent or cap-independent translation processes. Viruses depend on the host translation machinery for viral protein synthesis. Therefore, viruses have evolved clever strategies to utilize the host translation machinery. Earlier studies have shown that genotype 1-Hepatitis E virus (g1-HEV) utilizes both cap-dependent and cap-independent translation machineries for its replication and proliferation. Cap-independent translation in g1-HEV is driven by an eighty seven nucleotide-long RNA element which acts as a noncanonical, internal ribosome entry site like (IRESl) element. Here, we have identified the RNA-protein interactome of the HEV IRESl element and characterized the functional significance of some of its components. Our study reveals indispensable roles of host ribosomal protein RPL5 and DHX9 (RNA helicase A) in mediating efficient translation from the IRESl element and establish the function of HEV IRESl as a bonafide internal ribosome entry site. Author summaryProtein synthesis is a fundamental process for survival and proliferation of all living organisms. Majority of cellular proteins are produced through cap-dependent translation. Cells also utilize a variety of cap-independent translation processes to synthesize essential proteins during stress. Viruses depend on the host cell translation machinery to synthesize their own proteins. Hepatitis E virus is a major cause of hepatitis worldwide. The viral genome is a capped positive strand RNA. Viral non-structural and structural proteins are synthesized through a cap-dependent translation process. An earlier study from our laboratory reported the presence of a fourth ORF in genotype 1-HEV, which produced the ORF4 protein using a cap-independent internal ribosome entry site-like (IRESl) element. In the current study, we identified the host proteins that associate with the HEV-IRESl RNA and generated the RNA-protein interactome. Through a variety of experimental approaches, our data proves that HEV-IRESl is a bonafide internal ribosome entry site.

microbiology↗

bioRxiv2022

Glycation renders alpha-synuclein oligomeric strain and modulates microglia activation

-Synuclein is known to involve in the pathogenesis of Parkinsons diseases (PD) and related disorders. However, it is unclear how its aggregation causes neuronal degeneration and neuroinflammation. Due to intrinsic disorder nature, -synuclein produces a large number of structural ensembles and diverse aggregation intermediates. The post-translational modifications add a new layer of complexity to the aggregation mechanism. Recently, it has been demonstrated that glycation of -synuclein restricts into oligomeric intermediates and causes neuronal toxicity. However, the understanding of aggregation mechanism, dopaminergic neuronal death, and neuroinflammation by the glycated -synuclein is yet to be elucidated. The present study aims to address how glycated synuclein differs in oligomerization and neuroinflammation. The glycation of -synuclein perturbs the aggregation kinetics and prevents the fibrilization through the alteration of surface charges of N-terminal domain residues which prevents membrane binding and seed amplification mechanism. Mass spectrometry-based proteomics analysis of BV2 cells treated with glycated oligomers provides evidence of alteration of endocytic mechanism, mitochondrial dysfunction, and inflammatory cascade. Here, we show that -synuclein oligomers strongly bind to TLR2 and activate the TLR2 mediated signaling. However, glycated -synuclein oligomers impair the TLR2 binding and compromise TLR2 signaling. Interestingly, we also find that the glycated -synuclein oligomers favor NLRP3 inflammasome mediated neuroinflammation compared to non- glycated -synuclein oligomers. In conclusion, our findings suggest that microglia response towards -synuclein is conformation-specific and glycated oligomers can contribute to neurodegeneration differently.

neuroscience↗

bioRxiv2021

RNA-protein interaction analysis of SARS-CoV-2 5'- and 3'-untranslated regions identifies an antiviral role of lysosome-associated membrane protein-2

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is a positive-strand RNA virus. Viral genome is capped at the 5-end, followed by an untranslated region (UTR). There is poly-A tail at 3-end, preceded by an UTR. Self-interaction between the RNA regulatory elements present within 5- and 3-UTRs as well as their interaction with host/virus-encoded proteins mediate the function of 5- and 3-UTRs. Using RNA-protein interaction detection (RaPID) assay coupled to liquid chromatography with tandem mass-spectrometry, we identified host interaction partners of SARS-CoV-2 5- and 3-UTRs and generated an RNA-protein interaction network. By combining these data with the previously known protein-protein interaction data proposed to be involved in virus replication, we generated the RNA-protein-protein interaction (RPPI) network, likely to be essential for controlling SARS-CoV-2 replication. Notably, bioinformatics analysis of the RPPI network revealed the enrichment of factors involved in translation initiation and RNA metabolism. Lysosome-associated membrane protein-2a (Lamp2a) was one of the host proteins that interact with the 5-UTR. Further studies showed that Lamp2 level is upregulated in SARS-CoV-2 infected cells and overexpression of Lamp2a and Lamp2b variants reduced viral RNA level in infected cells and vice versa. In summary, our study provides an useful resource of SARS-CoV-2 5- and 3-UTR binding proteins and reveal the antiviral function of host Lamp2 protein. ImportanceReplication of a positive-strand RNA virus involves an RNA-protein complex consisting of viral genomic RNA, host RNA(s), virus-encoded proteins and host proteins. Dissecting out individual components of the replication complex will help decode the mechanism of viral replication. 5- and 3-UTRs in positive-strand RNA viruses play essential regulatory roles in virus replication. Here, we identified the host proteins that associate with the UTRs of SARS-CoV-2, combined those data with the previously known protein-protein interaction data (expected to be involved in virus replication) and generated the RNA-protein-protein interaction (RPPI) network. Analysis of the RPPI network revealed the enrichment of factors involved in translation initiation and RNA metabolism, which are important for virus replication. Analysis of one of the interaction partners of the 5-UTR (Lamp2a) demonstrated its antiviral role in SARS-CoV-2 infected cells. Collectively, our study provides a resource of SARS-CoV-2 UTR-binding proteins and identifies an antiviral role of host Lamp2a protein.

microbiology↗

bioRxiv2020

Induction of intracellular wild-type p53 amyloids leading to cellular transformation and tumor formation in mice

Tumor suppressor p53 mutations, with subsequent loss-of-tumor suppressive function and gain-of oncogenic functions, are associated with more than 50% of human cancers. Aggregation and amyloid formation are also mechanisms by which wild type and mutant p53 might be involved in cancer, but the direct evidence of how aggregated p53 acts as an oncogene is lacking. In this study, we directly demonstrate that wild-type p53 amyloid formation imparts oncogenic properties to normal cells. Cells with p53 amyloids show enhanced survival, apoptotic resistance with increased proliferation and migration rates. The tumorigenic potential of p53 amyloid transformed cells is further confirmed in a mice xenograft model, wherein the tumor showed p53 amyloid aggregates. Gene-expression analysis and proteomic profiling suggest that p53 amyloid formation triggers aberrant expression of pro-oncogenes while downregulating the tumor-suppressive genes. Interestingly, disaggregating p53 rescues the cellular transformation and also inhibits tumor development in mice. We propose that wild-type p53 amyloid formation can potentially contribute to the initiation of tumor development.

cancer biology↗