Biology subjects

Garg, M.

Publications and source records attributed to Garg, M..

17 recordsLinked to original sources

bioRxiv2026

A nanoscale atlas of extracellular vesicles and particles in Drosophila olfactory sensilla

Extracellular particles, including non-vesicular extracellular particles (NVEPs) and extracellular vesicles (EVs), are emerging as key contributors to sensory signaling, yet their ultrastructural organization within native tissues remains underexplored. Native tissues preserve extracellular particle organization and heterogeneity that are often lost during dissociation. Using cryofixation-based serial block-face scanning electron microscopy, we generated a nanoscale atlas of NVEPs and EVs across 352 Drosophila antennal olfactory sensilla ([~]70% coverage). Segmentation of more than 7,800 extracellular particles revealed distinct populations differing in morphology, size, electron density, and sensillum-class distribution. Analyses of EV biogenesis identified multivesicular bodies and membrane budding in auxiliary cells. Furthermore, sensilla housing degenerating neurons exhibited marked accumulation of EVs and NVEPs, accompanied by increased auxiliary-cell EV biogenesis. Together, these findings provide a large-scale ultrastructural characterization of extracellular particles in native sensory tissues and establish a foundation for understanding how extracellular particles are distributed, generated, and function during sensory signaling and degeneration.

neuroscience↗

bioRxiv2026

Beyond Metabolites: A Wearable Differential Biointerface Integrating Antibody and Aptamer Probes for the Real-Time Tracking of Proteins In Vivo

Continuous monitoring of protein biomarkers could transform the management of acute and chronic diseases. Despite tremendous potential, wearable health monitors have remained largely limited to metabolites and small molecules. A key challenge is the limited availability of biointerfaces that reversibly track low-abundance proteins in vivo without user intervention. Here, we present the Differential Aptalyzer, a minimally invasive hydrogel microneedle platform for continuous monitoring of proteins in skin interstitial fluid. The platform combines high-affinity antibodies for selective target capture with aptamers for reversible electrochemical signal transduction. When integrated into a differential electrochemical chip and pulse-assisted sensor regeneration, this approach enables continuous monitoring of proteins in a wearable format. Using cardiac troponin I (cTnI) as a clinically-relevant model analyte, Differential Aptalyzer offers a broad dynamic range (0.003-0.640 ng/mL) and strong specificity against interfering proteins. Importantly, this platform reliably tracks both rising and falling exogenous cTnI levels injected into healthy mice, as well as endogenously elevated cTnI in a double-knockout mouse model of coronary artery disease, demonstrating its capability in continuous protein monitoring and identifying coronary artery disease cohorts.

bioengineering↗

bioRxiv2025

NLRP3 Inflammasome Exhibits Context-Dependent Roles in Glioblastoma-Astrocyte Crosstalk

Glioblastoma (GBM) is a highly aggressive brain tumor characterized by molecular and cellular heterogeneity and poor patient survival. NLRP3 inflammasome regulates inflammation and cell death with context-specific roles in cancer, but its functions in GBM tumour and astrocyte interactions remain unclear. In this study, we analyzed NLRP3 expression and function in GBM cell lines (LN-229 and LN18), astrocytes (SVG), patient-derived tissues, and organoids. Basal NLRP3 expression was higher in astrocytes than in GBM cells and increased after LPS stimulation, altering astrocyte morphology and NLRP3 subcellular localization. siRNA-mediated silencing of NLRP3 reduced GBM proliferation, migration, and viability in GBM cells, while enhancing proliferation and cytokine secretion in astrocytes, highlighting its context-dependent effects. NLRP3 deficiency exhibited reciprocal cytokine paracrine signaling, with GBM cells releasing elevated levels of IL-6 and TNF-, and astrocytes releasing elevated levels of IL-1{beta}. Glyburide treatment reduced NLRP3 expression and IL-1{beta} release in GBM cells but elevated NLRP3 and IL-1{beta} in astrocytes. Overall, these data reveal NLRP3s dual roles in GBM-astrocyte crosstalk, suggesting cell-type-selective inhibition for therapeutic exploration.

cancer biology↗

bioRxiv2025

NLRP12-mediated Glioblastoma-Astrocyte Cross-talk Promotes Tumor Growth

Nucleotide-binding domain leucine-rich repeat-containing receptors (NLR) are cytosolic pattern recognition receptors that regulate inflammation by sensing pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). NLRP12 is a cytosolic protein with inflammation-promoting and inflammation-attenuating properties. NLRP12 exhibits tumor-suppressive or tumor-promoting effects that may be cancer, cell-type, context-dependent, aided by differences in the microenvironment contributing to the pathophysiology of hepatocellular carcinoma, prostate cancer, colitis-associated cancer, and glioblastoma (GBM). GBM is a grade IV malignant brain tumor with poor patient survival and high tumor recurrence due to a heterogeneous cell population and angiogenesis. Our previous research reported NLRP12 as a potential prognostic marker for GBM with high expression in GBM patient tissues. In the present study, we investigated the role of NLRP12-mediated signalling between GBM and tumor-adjacent astrocytes, using a comprehensive panel of experimental models, including LN-229 GBM and SVG astrocyte cell lines, cell line-derived spheroids, patient-derived primary glioma cells, and patient-derived glioma organoids. We report that NLRP12 deficiency reduces cell proliferation and viability in the LN-229 cells, but increases these parameters in SVG cells. Furthermore, NLRP12-deficient LN-229 cells display attenuated ability to form three-dimensional spheroids, indicating a role of NLRP12 in anchorage-independent growth, which is considered a hallmark of tumorigenicity. Analysis of patient-derived glioma tissue and patient-derived GBM organoids revealed differential expression of NLRP12. Our findings suggest that NLRP12 modulates GBM cell proliferation, viability, and anchorage-independent growth in a cell-context dependent manner. The cell-type-specific roles of NLRP12 may underlie its complex contribution to GBM pathophysiology with implications for therapy and prognosis. SummaryNLRP12, a cytosolic regulator of inflammation, exhibits context-dependent roles in cancer. Its deficiency reduces glioblastoma cell proliferation, viability, and spheroid formation, while enhancing these properties in astrocytes, indicating a cell-type-dependent role for NLRP12 in GBM progression.

cancer biology↗

bioRxiv2025

Quantifying Misuse of Color in Biological Research

Colors are widely used to report biological research data. Effective interpretation of colors relies on accurate, intuitive, and accessible colormaps that are properly labeled. Misuse of colormaps, such as using rainbow, mismatched, and other inaccessible colormaps, hinders reader interpretation. Despite their ubiquitous use to represent biological data, the prevalence of colormap misuse has not been quantified. Using established guidelines, we analyzed over 6,000 articles in 10 high-impact biological journals spanning 2020-2024 to quantify the prevalence of colormap use and misuse. Over 67% of articles contain at least one colormap, of which 81% contain some form of misuse. Among the over 11,000 acquired colormap-associated figures, 60% contain some form of misuse. Heatmaps, scatter plots, images, and image overlays are the most commonly used figures with colormaps. These statistics vary by journal but remain constant over time, demonstrating the urgent need to increase awareness and education about color-based data reporting guidelines.

scientific communication and education↗

bioRxiv2025

SNHG10 promote tumorigenesis via miR-150/VEGFA/EGFR/AKT/ERK/mTOR axis and gemcitabine resistance in PDAC

SNHG10 emerged as a key regulator in progression and metastasis of cancers. However, potential of SNHG10 in PDAC tumorigenesis, gemcitabine resistance, and underlying mechanisms remains poorly understood. We observed significant upregulation of SNHG10 in 179 PDAC cases, revealing a positive correlation with clinical stages. Our results showed a significant SNHG10 overexpression in several PDAC cells. Downregulation of SNHG10 significantly decreased the proliferation, clonogenicity, EMT, tumor growth in the xenograft model, and the induction of cell cycle arrest and apoptosis of PDAC cells. Mechanistically, SNHG10 knockdown significantly inhibited the expression of vimentin, N-cadherin, survivin, CDK4, CDK6, cyclin B1, cyclin D1, aurora kinase A, and B, with an increased expression of E-cadherin and p21. RNA Immunoprecipitation data displayed physical interaction among SNHG10, miR-150-5p, and VEGFA in PDAC cells. SNHG10 silencing led to the significant induction of miR-150-5p, which repressed VEGFA expression in PDAC cells. SNHG10 downregulation enhanced gemcitabine sensitivity in PDAC cells. SNHG10 silencing suppressed the phosphorylation of EGFR, AKT, ERK1/2, mTOR, and c-MET pathways. Silencing SNHG10 and its regulated signalling offers a novel prospective therapeutic strategy.

cancer biology↗

bioRxiv2025

RGG peptide induces the disassembly of disease-relevant FUS and TDP43 condensates

Mislocalization and cytoplasmic condensation of nuclear proteins, such as FUS and TDP43, are key features of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). However, mechanisms governing the disassembly of these pathological condensates remain elusive. Here, we identify a disordered RGG peptide as a disassembly factor for mutant FUS and TDP43 condensates. Using yeast, mammalian cells, and in vitro assays, we observe that an RGG motif reduces condensate burden and toxicity while restoring nuclear localization and RNA regulatory defects associated with the FUS-P525L mutant. The RGG motif interacts with FUS, competitively inhibiting FUS self-association. Overall, our findings uncover a direct role for a disordered RGG motif in the disassembly of ALS-associated condensates, highlighting the possibility of a new therapeutic for post-symptomatic ALS.

cell biology↗

bioRxiv2024

Innate Immune Receptor NLRX1: Potential Modulator of Glioblastoma Pathophysiology

Gliomas are primary brain tumors that develop from glial cells within the central nervous system and are among the deadliest human cancers. Glioblastoma (GBM) is the most malignant form of glioma. NLRX1 is an innate immune pattern recognition receptor that exhibits tumor-suppressive and tumor-promoting effects that may be cancer or cell-type, context-dependent, aided by differences in the microenvironment. Here, we report that NLRX1 is differentially expressed in microglia, astrocytes, GBM cell lines, and glioma patient tissues. siRNA-mediated silencing of Nlrx1 decreases the ability of the GBM cell line, LN-229, to proliferate and migrate. Nlrx1-/- GBM cells exhibit attenuated ability to generate 3D spheroids and enhanced capability to form tunneling nanotubes. Moreover, Nlrx1-/- GBM cells show decreased expression of autophagy markers, suggesting that NLRX1 plays a role in maintaining autophagy in GBM. In summary, our findings indicate that NLRX1 may modulate GBM pathophysiology by regulating GBM cell proliferation, migration, and metabolism. We believe our understanding of NLRX1 in GBM pathophysiology paves the potential development of GBM-targeting therapeutics that may delay disease progression and/or improve survival.

cancer biology↗

bioRxiv2024

Detection of Antibodies Against the African Parasite Trypanosoma brucei Using Synthetic glycosylphosphatidylinositol oligosaccharide fragments

Trypanosoma brucei (T. brucei) parasites cause two major infectious diseases in Africa: African trypanosomiasis in humans (HAT) and Nagana in animals. Despite the enormous economic and social impact, vaccines and reliable diagnostic measures are still lacking for these diseases. The main obstacle to developing accurate diagnostic methods and an active vaccine is the parasites ability for antigenic variation and impairment of B cell maturation, which prevents the development of a long-lasting, effective immune response. The antigenic variation is sustained by random gene switching, segmental gene conversion, and altered glycosylation states of solvent-exposed regions of the corresponding variant surface glycoproteins (VSG). These glycoproteins use a glycosylphosphatidylinositol (GPI) anchor for attachment to the membrane. GPIs of T. brucei have specific branched structures that are further heterogeneously galactosylated. We synthesized a glycan fragment library containing T. brucei GPIs most prominent structural features and performed an epitope mapping using mice and human sera of infected specimens using glycan microarrays. The studies indicate that in contrast to VSG, T. brucei GPIs are recognized by both short-lived IgM and long-lasting IgG, indicating a specific immune response against GPI structures. These findings enable the development of diagnostic tests based on synthetic antigens for reliable diagnosis of human African trypanosomiasis and Nagana.

biochemistry↗

bioRxiv2023

Repurposing The Dark Genome. III - Intronic Proteins

Based on the expression patterns, genomes are viewed as a collection of protein-coding, RNA-coding, and non-expressing DNA sequences. Unlike most prokaryotes, eukaryotic gene expression comes with an additional step called alternative splicing. During the maturation process, different combinations of exons are spliced out and joined together resulting in the formation of mRNA isoforms. After removal from pre-mRNA, introns may be degraded by cellular exonucleases or form long non-coding RNAs (lncRNAs), or temporarily retained in the nucleus for regulating gene expression. We asked: Do introns have an unutilized potential for encoding proteins? If introns had an opportunity of getting translated, what kind of peptides or proteins, would they make? This study is based on the hypothesis of making functional proteins from leftover introns and is an extension of the original work of making functional proteins from the E. coli intergenic sequences (Dhar et al., 2009). Here full-length introns were computationally translated into proteins to study their potential structural, physicochemical, functional, and cellular location properties. Experimental validation is underway for a detailed understanding of the biology of intronic proteins. A synthetic intronic protein repository would provide an opportunity to design first-in-the-class molecules toward functional endpoints.

synthetic biology↗

bioRxiv2023

Repurposing the dark genome. I - Antisense Proteins

From the functional standpoint, the genome may be considered a collection of three types of sequences: protein encoding, RNA encoding, and non-expressing. Based on the standard sequencing and annotation work, it is now well accepted that a small proportion of the genome has been allocated the job of encoding proteins, while most of the genome encodes RNA, and some DNA sequences are not used for expression. The exact ratio among these three types of sequences varies based on the organism. We asked: Is it possible to artificially encode protein and peptide sequences from naturally non-expressing (dark genome) sequences? This led to proof of the concept of making functional proteins from the intergenic sequences of E.coli (Dhar et al 2009). This study is an extension of the original concept and has been organized around antisense DNA sequences. The full-length antisense gene equivalents in forward and reverse orientations were computationally studied for their structural, cellular location, and functional properties, leading to many interesting observations. The current study points to a huge untapped genomic space that needs to be examined from cell physiology, evolutionary, and application perspectives.

synthetic biology↗

bioRxiv2022

Transcriptional signature pattern in black, blue and purple wheat and impact on seed pigmentation and other associated features: Comparative transcriptomics, genomics and metabolite profiling

Anthocyanin biosynthesis in plants is complex, especially in a polyploid monocot wheat plant. Using whole-genome sequencing, transcriptomics, and LC-MS/MS, we investigated anthocyanin production in pigmented (black, blue, and purple) wheat seeds. According to differential gene expression profiling, 2AS-MYC, 7DL-MYB, WD40 regulatory genes controls purple pericarp coloration, 4DL-MYC, 2AS-MYC, 7DL-MYB, WD40 controls blue aleurone coloration, and 4DL-MYC, 7DL-MYB, WD40 controls black aleurone colour. We believe that at least one MYC and MYB isoform is sufficient to regulate the anthocyanin synthesis in pericarp or aleurone. Based upon the reduced expressions of the genes belonging to the 4D, SSR molecular marker mapping, variant calling using genome sequencing and IGV browser gene structure visualization, it was inferred that the advanced black and blue wheat lines were substitution lines (4E{4D}), with very small recombinations. Pericarp anthocyanin profiling is controlled by a mutation in chromosome 2AS of purple wheat, and environmental variations more influence pigmented pericarp trait. The expression patterns of anthocyanin structural and other genes varied in different colored wheat, corroborating differences in agronomical metrics.

plant biology↗

bioRxiv2021

Meta-analysis reveals consistent immune response patterns in COVID-19 infected patients at single-cell resolution

A number of single-cell RNA studies looking at the human immune response to the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been recently published. However, the number of samples used in each individual study typically is small, moreover the technologies and protocols used in different studies vary, thus somewhat restricting the range of conclusions that can be made with high confidence. To better capture the cellular gene expression changes upon SARS-CoV-2 infection at different levels and stages of disease severity and to minimise the effect of technical artefacts, we performed meta-analysis of data from 9 previously published studies, together comprising 143 human samples, and a set of 16 healthy control samples (10X). In particular, we used generally accepted immune cell markers to discern specific cell subtypes and to look at the changes of the cell proportion over different disease stages and their consistency across the studies. While half of the observations reported in the individual studies can be confirmed across multiple studies, half of the results seem to be less conclusive. In particular, we show that the differentially expressed genes consistently point to upregulation of type I Interferon signal pathway and downregulation of the mitochondrial genes, alongside several other reproducibly consistent changes. We also confirm the presence of expanded B-cell clones in COVID-19 patients, however, no consistent trend in T-cell clonal expansion was observed.

bioinformatics↗

bioRxiv2020

Efficient Inhibition of O-glycan biosynthesis using the hexosamine analog Ac5GalNTGc

There is a critical need to develop small molecule inhibitors of mucin-type O-linked glycosylation. The best known reagent currently is peracetylated benzyl-GalNAc, but it is only effective at millimolar concentrations. This manuscript demonstrates that Ac5GalNTGc, a peracetylated C-2 sulfhydryl substituted GalNAc, fulfills this unmet need. When added to cultured leukocytes, breast and prostate cells, Ac5GalNTGc increased cell surface VVA-binding by ~10-fold, indicating truncation of O-glycan biosynthesis. Cytometry, mass spectrometry and Western blot analysis of HL-60 promyelocytes demonstrate that 50-80M Ac5GalNTGc prevented elaboration of 30-60% of the O-glycans beyond the Tn-antigen (GalNAc1-Ser/Thr) stage. The effect of the compound on N-glycans and glycosphingolipids was small. Glycan inhibition induced by Ac5GalNTGc resulted in 50-80% reduction in leukocyte sialyl-Lewis-X expression, and L-/P-selectin mediated rolling under flow. Ac5GalNTGc was pharmacologically active in mouse. It reduced neutrophil infiltration to sites of inflammation by ~60%. Overall, Ac5GalNTGc may find diverse applications as a potent inhibitor of O-glycosylation.

biochemistry↗

bioRxiv2020

Cell state diversity promotes metastasis through heterotypic cluster formation in melanoma

In melanoma, transcriptional profiling has revealed multiple co-existing cell states, including proliferative versus invasive sub-populations that have been posited to represent a "go or grow" tradeoff. Both of these populations are maintained in tumors, but how they physically interact to promote metastasis is unknown. We demonstrate that these subpopulations form spatially structured heterotypic clusters that cooperate in the seeding of metastasis. We unexpectedly found that INV cells were tightly adherent to each other, and formed clusters with a rim of PRO cells. Intravital imaging demonstrated cooperation between these populations, in which the INV cells facilitated the spread of less metastatic PRO cells. We identified the TFAP2 neural crest transcription factor as a master regulator of both clustering and the PRO/INV states. Our data suggest a framework for the co-existence of these two divergent cell populations, in which differing cell states form heterotypic clusters that promote metastasis via cell-cell cooperation.

cancer biology↗

bioRxiv2020

PSP2, a gene encoding RGG-motif protein, is a novel suppressor of clathrin heavy chain deficiency

Clathrin, made up of the heavy- and light-chains, constitutes one of the most abundant protein in vesicles involved in intracellular protein trafficking and endocytosis. YPR129W, which encodes RGG-motif containing translation repressor was identified as a part of multi-gene construct (SCD6) that suppressed clathrin deficiency. However, the contribution of YPR129W alone in suppressing clathrin deficiency has not been documented. In this study we identify YPR129W as a necessary and sufficient gene in a multigene construct SCD6 that suppresses clathrin deficiency. Importantly, we identify cytoplasmic RGG-motif protein encoding gene PSP2 as a novel suppressor of clathrin deficiency. Three other RGG-motif protein encoding genes SBP1, DED1 and GBP2 do not suppress clathrin deficiency. DHH1, a DEAD-box RNA helicase with translation repression activity also fails to rescue clathrin deficiency. -factor secretion assay suggests that suppression of clathrin deficiency by SCD6 and PSP2 is not mediated by the rescue of the trans-Golgi network (TGN) protein sorting defect observed in the absence of CHC1. Detailed domain analysis of the two suppressors reveals that the RGG-motif of both Scd6 and Psp2 is important for suppressing clathrin deficiency. Additionally, the Lsm domain deletion as well as the arginine to alanine mutation in the arginine methylation defective (AMD) mutant render Scd6 defective in suppressing clathrin deficiency. Overall based on our results using SCD6 and PSP2 proteins, we identify a novel role of RGG-motif in suppressing clathrin deficiency. Since both the suppressors are RNA-binding granule-resident proteins, this study opens an exciting avenue for exploring the connection between clathrin function and cytoplasmic RNA metabolism.

cell biology↗

bioRxiv2020

Tumour gene expression signature in primary melanoma predicts long-term outcomes: A prospective multicentre study

PurposePredicting outcomes after resection of primary melanoma remains crude, primarily based on tumour thickness. We explored gene expression signatures for their ability to better predict outcomes. MethodsDifferential expression analysis of 194 primary melanomas resected from patients who either developed distant metastasis (n=89) or did not (n=105) was performed. We identified 121 metastasis-associated genes that were included in our prognostic signature, "Cam_121". Several machine learning classification models were trained using nested leave- one-out cross validation (LOOCV) to test the signatures capacity to predict metastases, as well as regression models to predict survival. The prognostic accuracy was externally validated in two independent datasets. ResultsCam_121 performed significantly better in predicting distant metastases than any of the models trained with the clinical covariates alone (pAccuracy=4.92x10-3), as well as those trained with two published prognostic signatures. Cam_121 expression score was strongly associated with progression-free survival (HR=1.7, p=3.44x10-6), overall survival (HR=1.73, p=7.71x10-6) and melanoma-specific survival (HR=1.59, p=0.02). Cam_121 expression score also negatively correlated with measures of immune cell infiltration ({rho}=-0.73, p<2.2x10-16), with a higher score representing reduced tumour lymphocytic infiltration and a higher absolute 5-year risk of death in stage II melanoma. ConclusionsThe Cam_121 primary melanoma gene expression signature outperformed currently available alternatives in predicting the risk of distant recurrence. The signature confirmed (using unbiased approaches) the central prognostic importance of immune cell infiltration in long-term patient outcomes and could be used to identify stage II melanoma patients at highest risk of metastases and poor survival who might benefit most from adjuvant therapies. Translational relevancePredicting outcomes after resection of primary melanoma is currently based on traditional histopathological staging, however survival outcomes within these disease stages varies markedly. Since adjuvant systemic therapies are now being used routinely, accurate prognostic information is needed to better risk stratify patients and avoid unnecessary use of high cost, potentially harmful drugs, as well as to inform future adjuvant strategies. The Cam_121 gene expression signature appears to have this capability and warrants evaluation in prospective clinical trials.

bioinformatics↗