Biology subjects

Iqbal, J.

Publications and source records attributed to Iqbal, J..

17 recordsLinked to original sources

bioRxiv2026

Omics-analyses of Fermented Onion pickle in Shaping Gut Microbiota and Immune Response in Women: A Community-Based Trial in Pakistan

A fermented-food intervention trial conducted in Pakistan suggested beneficial changes in the composition of the gut microbiota in healthy women. Using a subset (n=17) of the same participants, this study further investigates the impact of fermented food (onion pickle) on gene expression levels using RNA transcriptomics, with a focus on host-microbiome interactions. After consuming pickles (50g/day) for eight weeks, blood and stool samples of participants were collected at baseline and post-intervention to assess inflammatory markers, 16S rRNA gene sequencing, clinical parameters, and RNA sequencing. Among inflammatory biomarkers, lipocalin (LCN-2) levels significantly decreased (pre=86.5{+/-}80.1ng/mL, post=61.0{+/-}59.0 ng/mL, p=0.04, paired T-test). Additionally, the intervention downregulated pathways (p<0.05) involved host responses to microbial stimuli, including response to bacterial origin, chemotaxis, and response to lipopolysaccharide. In gut microbiota, observed -diversity significantly increased post-intervention (p=0.02). Linear discriminant analysis effect size (LEfSe) revealed differential expressions (LDA [≥] 2.0) of Olsenella and Coriobacteriales at week-8, where Olsenella sp. showed a significant negative correlation with LCN-2 (R=-0.36, p<0.05, Spearmans correlation). These findings suggest that fermented onion pickle consumption for eight weeks modestly alters gut microbial diversity and composition and is associated with reduced inflammatory markers and altered host immune-related gene expression, potentially improving intestinal health. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=81 SRC="FIGDIR/small/711246v1_ufig1.gif" ALT="Figure 1"> View larger version (27K): org.highwire.dtl.DTLVardef@18679e0org.highwire.dtl.DTLVardef@1ab62eeorg.highwire.dtl.DTLVardef@ec318forg.highwire.dtl.DTLVardef@a9b94c_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2026

Safety Signals Enable Single-Episode Active Avoidance paradigm and Expose Threat Generalization in Tuberous Sclerosis Complex

Animals must flexibly discriminate between threat and non-threat to deploy adaptive defensive strategies. We introduce a single-episode differential signaled active avoidance (DSAA) paradigm that temporally dissociates acquisition, consolidation, and retrieval of instrumental avoidance memory. Interleaving a behaviorally noncontingent neutral cue (CS-) with a threat-predictive, behaviorally contingent cue (CS+) enhanced long-term memory without altering acquisition, demonstrating that differential contingency structure selectively reinforces memory consolidation rather than influencing learning performance. Naive animals inferred contingencies within a single episode, and discrimination achieved during training predicted retrieval precision. However, discrimination operated within defined boundary conditions: overtraining or elevated threat intensity destabilized cue specificity and promoted persistent avoidance generalization. Under high-threat conditions, freezing and shuttling co-emerged as complementary defensive responses, indicating a shift from precise cue-based encoding to a generalized defensive state. Remote retrieval recruited oxytocin receptor-expressing cells in the medial prefrontal cortex and activated mTORC1-dependent translational signaling, implicating protein synthesis in maintenance of discriminative avoidance memory. In a Tuberous Sclerosis Complex model with Tsc2 haploinsufficiency in oxytocin-responsive cells, males displayed intact acquisition but generalized avoidance at both recent and remote time points, a deficit not rescued by additional training. These findings identify oxytocin-modulated translational control as a molecular gate stabilizing threat-safety discrimination and show that disruption of this axis - by excessive threat or reduced Tsc2 gene dosage - biases memory toward pathological generalization, providing a mechanistic framework for safety-learning deficits in neurodevelopmental and anxiety-related disorders.

animal behavior and cognition↗

bioRxiv2026

A prelimbic molecular clock of protein synthesis for memory persistence

Emotionally salient associative memories can endure for long periods, yet the mechanisms that determine their long-term stability remain unclear. Here we show that the prelimbic (PL) cortex integrates temporally structured translational programs to control both the consolidation and reconsolidation of cued threat memories. Using Pavlovian threat conditioning with in vivo fiber photometry, we found that PL calcium dynamics tightly track memory strength: discrete threat-predictive cues evoked robust activity during recent and single-timepoint remote retrieval, whereas prior retrieval selectively weakened remote expression, independent of contextual influences. Translational profiling of PL Camk2a cells uncovered a biphasic consolidation program, with an early phase characterized by ER stress-linked translational repression and robust oligodendrocyte plasticity, followed by a delayed phase engaging synaptic growth pathways. Loss- and gain-of-function approaches demonstrated that eIF2-regulated, cap-independent translation is essential for recent consolidation and for the enduring stabilization of remote memory, whereas retrieval-induced destabilization engages a mechanistically distinct, eIF4E-dependent translational pathway required for reconsolidation. These findings identify the PL cortex as a dynamic node in which discrete modes of translational control govern the long-term persistence of emotional memories.

neuroscience↗

bioRxiv2025

Development of the Early Childhood Duodenum across Ancestry, Geography and Environment

During early childhood, the proximal small intestinal mucosa plays a central role in growth, metabolism, immune priming, and neuronal development. Yet the cellular architecture and environmental responsiveness of the human small intestinal mucosa during this period remain poorly defined. Here, we generate a comprehensive cellular and spatial map of the duodenum from 87 children aged 6 months to 13 years, representing diverse ancestries and geographic contexts. This atlas integrates single-cell transcriptomic and spatial profiling with data on diet, social drivers of health, and environmental exposures. Using these data, we define mucosal cellular composition and chart its developmental trajectory in early childhood. Comparative analyses of children residing in the United States (US) and Pakistan reveal a differentiated enterocyte subset expressing the aquaglyceroporin, AQP10 (AQP10+ enterocyte), that is enriched in children from the US. We show that emergence of this enterocyte state depends on lipid exposure to intestinal stem cells and correlates with dietary fat intake. We also identify a previously-undescribed thyrotropin-releasing hormone (TRH+) enteroendocrine cell and provide evidence for a local endocrine-epithelial-lymphocyte circuit. Our work establishes a detailed framework for pediatric duodenal mucosal development and illuminates how intestinal cellular dynamics are shaped by age and environment.

developmental biology↗

bioRxiv2025

A novel chitinase-like family of candidate effectors unique to aphids

Molecular interactions between aphids and plants include delivery of salivary effector proteins into host cells, acting as virulence factors to suppress host immunity, or as avirulence functions triggering immune activation. However, understanding of virulence and avirulence mechanisms in aphid-plant systems is currently limited. Here, we report discovery of an effector candidate family that is unique to aphids. Using functional genomics data on divergent pea aphid (Acyrthosiphon pisum) genotypes and their F1 progeny, we filtered for differentially expressed saliva proteins that co-segregated with virulence or avirulence phenotypes. LOC100575698 (ACPISUM_029930), annotated as an uncharacterized protein, was the sole candidate effector for which RNA-Seq and saliva proteomics data showed significantly different expression both between avirulent and virulent parents and between their segregating F1 progeny, with this gene upregulated in avirulent genotypes. BLASTP searches revealed multiple divergent homologs only in genomes of the Aphidomorpha infra-order, suggesting a hitherto undefined ancient aphid-specific gene family. AlphaFold models indicate strong structural similarities but weak sequence homology to chitinases. Because the aphid-specific clade all lack canonical DxxDxDxE motifs for catalytic activity, we designate the proteins as a novel CHitinase-Like (CHL) family. Association of ACPISUM_029930 (ApCHL1) with avirulence was further supported by co-segregating SNPs and a genotype-specific alternatively spliced isoform. We hypothesise that CHL proteins may function similarly to phylogenetically unrelated chitin-binding fungal effectors that sequester chitin, also present in aphid stylets, potentially preventing defence activation through plant chitin receptors and/or blocking chitin degradation by host-secreted chitinases.

molecular biology↗

bioRxiv2025

Functional genomics and tumor microenvironment analysis reveal prognostic biological subtypes in Mantle cell lymphoma

Mantle cell lymphoma (MCL) is a genetically and clinically heterogeneous B-cell malignancy. We studied two MCL cohorts with differing treatment patterns: one enriched for immunochemotherapy, the other for chemotherapy alone. TP53 alterations were consistently associated with poor prognosis, whereas ATM mutations correlated with improved outcomes following rituximab-based chemotherapy. Based on recurrent genetic events, six clusters were identified and refined into three prognostic groups: high-risk (TP53 mutations and deletions at 17p13.3, 13q14.2, and 19p13.3), intermediate-risk (ATM and epigenetic regulator mutations, or gains at 8q/17q/15q), and low-risk (lacking TP53 alterations, rare ATM mutations without 11q deletions, gains at 3q, deletions at 6q). Transcriptomic analysis revealed enrichment of proliferation, metabolism-promoting gene signatures in high-risk; angiogenesis and NOTCH signaling in intermediate-risk; and proinflammatory-related (i.e., IFN, TNF) in low-risk MCLs. Multi-proteomic spatial profiling using imaging mass cytometry (IMC) demonstrated enrichment of CD8 T cells with high expression of exhaustion markers and dominant population of myeloid cells skewed toward an M2-like phenotype. Compared to ATM-perturbed tumors, TP53-perturbed tumors exhibited enriched SOX11 tumor cells and enhanced tumor-immune cell interactions. Functional analysis revealed that p53 represses BCR signaling through PTPN6 activation. Collectively, these findings highlight distinct molecular and immune landscapes and reveal therapeutic vulnerabilities in high-risk TP53-altered MCL.

cancer biology↗

bioRxiv2025

Activation of cGAS-STING signaling pathway during HCV infection

Hepatitis C virus (HCV) is a major global health issue, infecting over 170 million people worldwide and leading to severe liver diseases, including cirrhosis and hepatocellular carcinoma. The ability of HCV to persist and cause chronic infection is partly due to its evasion of the hosts innate immune responses, particularly those mediated by the RIG-I-MAVS pathway, which is critical for antiviral defense. Studies have shown the crucial role genome sensing of DNA viruses by cyclic GMP-AMP synthase (cGAS) followed cGAMP production and activation of downstream effector STING (stimulator of interferon genes) to induce IFN-{beta}, however it is not understood in RNA viruses specially in HCV infection. In this study, we explored first time the mechanism of the cGAS-STING pathway in the context of HCV infection, specifically using the JFH-1 strain of HCV (genotype 2a). We observed that cGAS expression is significantly upregulated during the early HCV infection, leading to the production of the second messenger cyclic GMP-AMP (cGAMP), which in turn activates STING. This activation results in the significant induction of type I interferon responses, particularly interferon-{beta} (IFN-{beta}), which is essential for mounting an effective antiviral response. Moreover, our results demonstrated the translocation of cGAS and STING with cellular organelles such as the endoplasmic reticulum (ER) and mitochondria. This suggests that the cGAS-STING pathway is intricately linked with other cellular signaling networks in detecting and responding to HCV infection. Furthermore, knockdown experiments targeting cGAS, STING and RIG-I revealed that these proteins play a crucial role in suppressing HCV replication, underscoring their potential as therapeutic targets. These findings provide valuable insights into the molecular mechanisms of the cGAS-STING pathway in mediating the innate immune response against HCV. Understanding this pathways role in the immune defense against HCV opens up new possibilities for therapeutic strategies aimed at enhancing the hosts antiviral immunity and potentially developing new treatments for chronic HCV infection.

microbiology↗

bioRxiv2024

Multi-omics approaches define novel aphid effector candidates associated with virulence and avirulence phenotypes

BackgroundCompatibility between plant parasites and their hosts is genetically determined by both interacting organisms. For example, plants may carry resistance (R) genes or deploy chemical defences. Aphid saliva contains many proteins that are secreted into host tissues. Subsets of these proteins are predicted to act as effectors, either subverting or triggering host immunity. However, associating particular effectors with virulence or avirulence outcomes presents challenges due to the combinatorial complexity. Here we use defined aphid and host genetics to test for co-segregation of expressed aphid transcripts and proteins with virulent or avirulent phenotypes. ResultsWe compared virulent and avirulent pea aphid parental genotypes, and their bulk segregant F1 progeny on Medicago truncatula genotypes carrying or lacking the RAP1 resistance quantitative trait locus. Differential gene expression analysis of whole body and head samples, in combination with proteomics of saliva and salivary glands, enabled us to pinpoint proteins associated with virulence/avirulence phenotypes. There was relatively little impact of host genotype, whereas large numbers of transcripts and proteins were differentially expressed between parental aphids, likely a reflection of their classification as divergent biotypes within the pea aphid species complex. Many fewer transcripts intersected with the equivalent differential expression patterns in the bulked F1 progeny, providing an effective filter for removing genomic background effects. Overall, there were more upregulated genes detected in the F1 avirulent dataset compared with the virulent one. Some genes were differentially expressed both in the transcriptome and in the proteome datasets, with aminopeptidase N proteins being the most frequent differentially expressed family. In addition, a substantial proportion (27%) of salivary proteins lack annotations, suggesting that many novel functions remain to be discovered. ConclusionsEspecially when combined with tightly controlled genetics of both insect and host, multi-omics approaches are powerful tools for revealing and filtering candidate lists down to plausible genes for further functional analysis as putative aphid effectors.

genomics↗

bioRxiv2024

Diet-induced obesity mediated through Estrogen-Related Receptor α is independent of intestinal function

Obesity has become an epidemic, prompting advances in therapies targeting this condition. Estrogen-related receptor (ESRRA), a transcription factor, plays pivotal roles in energy metabolism across diverse tissues. Studies have demonstrated that loss of Esrra leads to fat malabsorption and resistance to diet-induced obesity. However, the reliance of these studies on germline Esrra mutants overlooks the tissue-specific implications of ESRRA in diet-induced obesity. Notably, Esrra exhibits high expression in the gastrointestinal (GI) tract relative to other tissues. Given the critical role of the GI tract in dietary lipid metabolism, this study employs mouse genetics and genomics approaches to dissect the specific impact of intestinal ESRRA along with investigating its role in diet-induced obesity. Data TransparencyChIP-seq and RNA-seq data from this publication have been deposited to GEO accession numbers GSE269824 and GSE269825, respectively. Any additional information required to reanalyze the data reported in this paper is available from the corresponding author upon request. Grant SupportThis research was funded by grants from the National Institutes of Health (NIH) to M.P.V. (R01DK121915 and R01DK126446). K.V. was supported by an American Heart Association pre-doctoral fellowship (906006). S.K. was supported by a Rutgers DLS Summer Undergraduate Research Fellowship. A.L. was supported by grants from the NIH grant F31DK137596 and the NIH T32 Biotechnology Training Program (GM135141). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. DisclosuresThe authors declare no competing interests.

genetics↗

bioRxiv2023

De novo Protein Sequence Design Based on Deep Learning and Validation on CalB Hydrolase

Protein design is central to nearly all protein engineering problems, as it can enable the creation of proteins with new biological function, such as improving the catalytic efficiency of enzymes. As one of the key tasks of protein design, fixed-backbone protein sequence design aims to design novel sequence that would fold into a given protein backbone structure. However, current sequence design methods have limitations in terms of low sequence diversity and experimental validation of designed protein function, which cannot meet the needs of functional protein design. We firstly constructed Graphormer-based Protein Design (GPD) model that directly applies Transformer to graph-based representation of 3D protein structure, and added Gaussian noise and sequence random mask to node features to improve the sequence recovery and diversity. Additionally, functional filtering based on the structure folding, solubility, and function were performed to improve the success rate in experiments. The process of "sequence design-functional filtering -functional experiment" was carried out for CalB hydrolase. The experimental results showed that the specify activity of designed protein improved 1.7 times than CalB wild type. This design and filtering platform will be a valuable tool for generating industrial enzymes and protein drugs with specific functions.

biochemistry↗

bioRxiv2022

An Alzheimer's disease patient-derived olfactory cell model identifies gene expression changes associated with cognition

An early symptom of Alzheimers disease (AD) is an impaired sense of smell, for which the molecular basis remains elusive. Here, we generated human olfactory neurosphere-derived (ONS) cells from people with AD and mild cognitive impairment (MCI), and performed global RNA sequencing to determine gene expression changes. ONS cells expressed markers of neuroglial differentiation, providing a unique cellular model to explore early AD-associated disease pathways. Our transcriptomics data from ONS cells revealed differentially expressed genes (DEGs) associated with cognitive processes in AD cells compared to MCI, or matched healthy controls (HC). A-Kinase Anchoring Protein 6 (AKAP6) was the most significantly altered gene in AD compared to both MCI and HC, and has been linked to cognitive function. The greatest change in gene expression of all DEGs occurred between AD and MCI. Gene pathway analysis revealed defects in multiple cellular processes with aging, intellectual deficiency and alternative splicing being the most significantly dysregulated in AD ONS cells. Our results demonstrate that ONS cells can provide a cellular model for AD that recapitulates disease-associated differences. We have revealed potential novel genes, including AKAP6 that may have a role in AD, particularly MCI to AD transition, and should be further examined.

neuroscience↗

bioRxiv2022

A Single Multipurpose FSH-Blocking Therapeutic for Osteoporosis and Obesity

Pharmacological and genetic studies over the past decade have established FSH as an actionable target for diseases affecting millions, notably osteoporosis, obesity and Alzheimers disease (AD). Blocking FSH action prevents bone loss, fat gain and AD-like features in mice. We recently developed a first-in-class, humanized, epitope-specific FSH blocking antibody, MS-Hu6, with a KD of 7.52 nM. Using a GLP-compliant platform, we now report the efficacy of MS-Hu6 in preventing obesity and osteoporosis in mice, and parameters of acute safety in monkeys. Biodistribution studies using 89Zr-labelled, biotinylated or unconjugated MS-Hu6 in mice and monkeys showed localization to bone, bone marrow and fat depots. MS-Hu6 displayed a {beta} phase t[1/2] of 13 days (316 hours) in humanized Tg32 mice, and bound endogenous FSH. We tested 215 variations of excipients using the protein thermal shift assay to generate a final formulation that rendered MS-Hu6 stable in solution upon freeze-thaw and at different temperatures, with minimal aggregation, and without self-, cross-, or hydrophobic interactions or appreciable binding to relevant human antigens. MS-Hu6 showed the same level of "humanness" as human IgG1 in silico, and was non-immunogenic in ELISPOT assays for IL-2 and IFN{gamma} in human peripheral blood mononuclear cell cultures. We conclude that MS-Hu6 is efficacious, durable and manufacturable, and is therefore poised for future human testing as a multipurpose therapeutic.

pharmacology and toxicology↗

bioRxiv2021

S. aureus-serine protease-like protein B (SplB) activates PAR2 and induces endothelial barrier dysfunction

Withdrawal StatementThe authors have withdrawn their manuscript owing to the following reason: Unfortunately, the preparation of the recombinant serine protease-like protein B (SplB) used in this study was found to contain impurities, so that the effects presented cannot be unambiguously attributed to the protease SplB. We therefore retract the manuscript from bioRxiv. We apologize for any inconvenience this may have caused. Therefore, the authors do not wish this work to be cited as reference for the project. We want to clarify that the issue was identified in the preparation of the SplB protein and does not reflect on the contributions of individual authors. If you have any questions, please contact the corresponding author.

immunology↗

bioRxiv2019

Data-driven inference of crosstalk in the tumor microenvironment

Signaling between cancer and nonmalignant (stromal) cells in the tumor microenvironment (TME) is key to tumorigenesis yet challenging to decipher from tumor transcriptomes. Here, we report an unbiased, data-driven approach to deconvolute bulk tumor transcriptomes and predict crosstalk between ligands and receptors on cancer and stromal cells in the TME of 20 solid tumor types. Our approach recovers known transcriptional hallmarks of cancer and stromal cells and is concordant with single-cell and immunohistochemistry data, underlining its robustness. Pan-cancer analysis reveals previously unrecognized features of cancer-stromal crosstalk. We find that autocrine cancer cell cross-talk varied between tissues but often converged on known cancer signaling pathways. In contrast, many stromal cross-talk interactions were highly conserved across tumor types. Interestingly, the immune checkpoint ligand PD-L1 was overexpressed in stromal rather than cancer cells across all tumor types. Moreover, we predicted and experimentally validated aberrant ligand and receptor expression in cancer cells of basal and luminal breast cancer, respectively. Collectively, our findings validate a data-driven method for tumor transcriptome deconvolution and establishes a new resource for hypothesis generation and downstream functional interrogation of the TME in tumorigenesis and disease progression.

cancer biology↗

bioRxiv2019

Pathognomonic and epistatic genetic alterations in B-cell non-Hodgkin lymphoma

B-cell non-Hodgkins lymphoma (B-NHL) encompasses multiple clinically and phenotypically distinct subtypes of malignancy with unique molecular etiologies. Common subtypes of B-NHL such as diffuse large B-cell lymphoma (DLBCL) have been comprehensively interrogated at the genomic level. But rarer subtypes such as mantle cell lymphoma (MCL) remain sparsely characterized. Furthermore, multiple B-NHL subtypes have thus far not been comprehensively compared using the same methodology to identify conserved or subtype-specific patterns of genomic alterations. Here, we employed a large targeted hybrid-capture sequencing approach encompassing 380 genes to interrogate the genomic landscapes of 685 B-NHL tumors at high depth; including DLBCL, MCL, follicular lymphoma (FL), and Burkitt lymphoma (BL). We identified conserved hallmarks of B-NHL that were deregulated in the majority of tumor from each subtype, including the frequent genetic deregulation of the ubiquitin proteasome system (UPS). In addition, we identified subtype-specific patterns of genetic alterations, including clusters of co-occurring mutations and DNA copy number alterations. The cumulative burden of mutations within a single cluster were more discriminatory of B-NHL subtypes than individual mutations, implicating likely patterns of genetic cooperation that contribute to disease etiology. We therefore provide the first cross-sectional analysis of mutations and DNA copy number alterations across major B-NHL subtypes and a framework of co-occurring genetic alterations that deregulate genetic hallmarks and likely cooperate in lymphomagenesis.

genomics↗

bioRxiv2018

Whole-Genome Genomics Correlates of Response To Anti-PD1 Therapy in Relapsed/Refractory Natural Killer/T Cell Lymphoma

AbstractThis study aims to identify recurrent genetic alterations in relapsed or refractory (RR) natural-killer/T-cell lymphoma (NKTL) patients who have achieved complete response (CR) with programmed cell death 1 (PD-1) blockade therapy. Seven of the eleven patients treated with pembrolizumab achieved CR while the remaining four had progressive disease (PD). Using whole genome sequencing (WGS), we found recurrent clonal structural rearrangements (SR) of the PD-L1 gene in four of the seven (57%) CR patients pretreated tumors. These PD-L1 SRs consist of inter-chromosomal translocations, tandem duplication and micro-inversion that disrupted the suppressive function of PD-L1 3UTR. Interestingly, recurrent JAK3-activating (p.A573V) mutations were also validated in two CR patients tumors that did not harbor the PD-L1 SR. Importantly, these mutations were absent in the four PD cases. With immunohistochemistry (IHC), PD-L1 positivity could not discriminate patients who archived CR (range: 6%-100%) from patients who had PD (range: 35%-90%). PD-1 blockade with pembrolizumab is a potent strategy for RR NKTL patients and genomic screening could potentially accompany PD-L1 IHC positivity to better select patients for anti-PD-1 therapy.

genomics↗

bioRxiv2017

DNA copy number gains of TCF4 (E2-2) are associated with poor outcome and the activated B-cell-like subtype of diffuse large B-cell lymphoma

The activated B-cell (ABC) subtype of diffuse large B-cell lymphoma (DLBCL) is characterized by the chronic activation of signaling initiated by immunoglobulin- (IgM). By analyzing DNA copy profiles of 1,000 DLBCLs, we identified gains of 18q21.2 as the most frequent genetic alteration in ABC-like DLBCL. We show that these alterations target the TCF4 (E2-2) transcription factor, and that over-expression of TCF4 leads to its occupancy on immunoglobulin gene enhancers and increased expression of IgM at the transcript and protein level. The TCF4 gene is one of the top BRD4-regulated genes in DLBCL. Using a BET proteolysis-targeting chimera (PROTAC) we show that TCF4 and IgM expression can be extinguished, and ABC-like DLBCL cells can be killed in vitro and in vivo. This highlights a novel genetic mechanism for promoting immunoglobulin signaling in ABC-like DLBCL and provides a functional rationale for the use of BET inhibitors in this disease.

genomics↗