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Singh, M.

Publications and source records attributed to Singh, M..

At least 37 records · Page 2Linked to original sources

Systematic Meta-Analysis of Published Transcriptomic Prognostic Signatures and Development of a Robust Multi-Cohort Prognostic Classifier for Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) exhibits pronounced molecular heterogeneity, yet the majority of published transcriptomic prognostic signatures suffer from limited reproducibility and have not achieved clinical translation. We systematically benchmarked 62 published TNBC prognostic signatures across 6 independent cohorts (n=1,357) using a unified analytical framework spanning multiple scoring algorithms, survival endpoints, and threshold strategies. While 17 signatures demonstrated consistent univariate prognostic associations, only 4 remained independently prognostic after adjustment for clinicopathological variables, and none achieved robustness across all analytical conditions-underscoring the fragility of existing classifiers. Leveraging genes with concordant survival associations across all 6 discovery cohorts, we identified a reproducible 15-gene directionally concordant gene set (DCGS) signature and distilled it into MetaSig-EFS, a 13-gene prognostic model optimized using a cohort-aware DeepSurv framework. MetaSig-EFS demonstrated robust cross-cohort generalizability, achieving validation concordance indices of 0.89 in GSE19615 and 0.69 in JBordet, with corresponding 3- and 5-year time-dependent AUROCs of 0.89 and 0.96 in GSE19615 and 0.80 and 0.71 in JBordet, respectively, while retaining independent prognostic value across established TNBC molecular sub-typing systems. Leveraging the TAHOE-100M transcriptomic perturbation atlas, we systematically prioritized candidate therapeutics through large-scale drug repurposing, identifying Paclitaxel as the top-ranked compound, followed by Venetoclax and Tucatinib. Together, these findings provide biologically informed and clinically actionable therapeutic hypotheses that extend the translational utility of our validated prognostic framework for TNBC risk stratification.

cancer biology↗

Sequence-to-function modeling uncovers the context-specific grammar of Drosophila chromatin insulation

Chromatin is organized into self-interacting topologically associating domains partitioned by boundary elements that insulate adjacent domains and restrict regulatory interactions. Yet, how sequence context and combinations of factors dictate boundary strength remains incompletely understood. Here we present Domino, a deep learning framework that maps genomic sequences to quantitative insulation scores defined directly from single-nucleosome resolution Drosophila melanogaster Micro-C data. Unlike traditional transcription factor motif scanning, Domino captures broad sequence context to resolve the functional contributions of individual sequence elements. We validate model predictions through experimental perturbations of insulator sequences. Model interpretation yields insulation-associated motifs genome-wide. Across 7,311 embryonic boundaries, Domino reveals a comprehensive insulation grammar defined by just 24 primary motifs that account for 59% of the boundaries, with an average of only two motifs per motif-containing boundary. Beyond known factors, we identify the zinc-finger proteins Trem, CG4854 and CG17385 as previously unreported insulation factors. We uncover distance- and orientation-dependent motif synergy, including a strict orientation preference of the prominent architectural factor M1BP. Finally, Domino traces tissue-specific shifts in the insulator landscape from the embryo to larval and adult brains, nominating new brain-specific insulation motifs. In sum, Domino provides a generalizable framework for decoding the regulatory logic of 3D genome architecture.

genomics↗

Coregulation by arcA and fnr protects Salmonella Typhimurium from bile stress by maintaining redox homeostasis and membrane integrity

Bile salts constitute a major antimicrobial barrier encountered by Salmonella Typhimurium during infections. Here, we identified the interplay of two global regulators, Fnr (fumarate and nitrate reductase) and ArcA (aerobic respiration control protein A), in determining adaptive responses to bile. We utilized WT, {Delta}fnr, {Delta}arcA and {Delta}arcA{Delta}fnr strains and compared the expression and functional responses of S. Typhimurium to bile. The highlights of this study are: First, the {Delta}arcA and {Delta}arcA{Delta}fnr strain form smaller colonies on LB agar plates and the {Delta}arcA{Delta}fnr strain displays lower motility. Second, qRT-PCR expression analysis demonstrates that fnr is induced early with bile, followed by arcA. Also, arcA transcripts are lower in the {Delta}fnr strain and fnr expression is also partially lower in the {Delta}arcA strain. Third, the {Delta}arcA and {Delta}fnr strains display partial sensitivity to bile, whereas the {Delta}arcA{Delta}fnr strain exhibits hypersensitivity to bile. Upon bile exposure, the {Delta}arcA{Delta}fnr strain displays elevated transcripts of the major antioxidant genes (sodA and katG) and outer membrane protein (ompC), higher induction of reactive oxygen species (ROS), and greater membrane damage. Fourth, intracellular nitrite is induced earlier than ROS with bile. Fifth, arcA and fnr protects S. Typhimurium from bile induced stress by activating the nitrate metabolism pathway, which lowers ROS. Functionally, pretreatment of the deletion strains with sodium nitrate reduces ROS, improves membrane integrity and survival with bile. Overall, these findings demonstrate that arcA and fnr function cooperatively to utilize alternate electron acceptors, reduce dependence on aerobic respiration and lower ROS to improve survival of S. Typhimurium during bile stress.

microbiology↗

Cortical Organoid Model of PPP2R5D Genetic Intellectual Disability Models Disease Severity Phenotype

Jordans Syndrome (JS) is a rare, neurodevelopmental disorder caused by de novo missense mutations in protein phosphatase 2 regulatory subunit Bdelta (PPP2R5D). JS is characterized by severe neurological impairments starting in early life. PPP2R5D encodes for B56{delta}, one of the regulatory subunits of protein phosphatase 2A (PP2A). PP2A is a heterotrimeric protein serine/threonine phosphatase that is highly expressed in the brain and the liver. Past studies have focused on PP2As role in liver and little is known about the holoenzymes behavior in neuronal cells. Although B56{delta} is known to play an important role in the substrate specificity of PP2A, the identification of validated downstream substrates in JS remains unclear. To better understand how the mutations affect neuronal cells, we developed cerebral cortical-like organoids from an engineered allele series of the most common JS mutations to characterize the physiological changes throughout different stages of neurodevelopment. Organoids were assessed for transcriptomic, protein, and electrophysiological changes utilizing bulk RNA sequencing, immunocytochemistry, Western Blot, and high-density MicroElectrode Array. The results identify differentially expressed genes and translated proteins, potential neuronal substrates, and significant electrophysiological signatures that suggest mutations in B56{delta} lead to variant-specific dysfunction of PP2A. Overexpression of PPP2R5D through AAV transduction of organoids rescued several phenotypes in the variants, suggesting different pathogenetic etiology underneath. Our findings successfully characterized cerebral cortical-like organoids in JS cell lines and demonstrated its potential as a model for studying neurodevelopmental disorder and for screening therapeutic approaches.

cell biology↗

Influenza-induced tuft cell expansion alters ILC-mediated inflammation

Tuft cells act as sentinels that amplify type 2 inflammation primarily by activating type 2 innate lymphoid cells (ILC2s). Although normally absent from the distal lung, ectopic tuft cells form after severe lung injury including influenza infection in mice. Here, we investigated the function of these ectopic tuft cells in shaping innate immunity following influenza injury. We observed that IFN{gamma} restrains tuft cell differentiation, whereas ILC2s drive tuft cell expansion, establishing a reciprocal regulatory axis. Tuft cell-deficient mice exhibited reduced eosinophilic inflammation and expansion of ILC1s and ILC3s after influenza injury resolution. Single-cell RNA-seq of influenza infected whole lung revealed transcriptional signatures consistent with type 1 pathway activation, type 2 suppression and oxidative stress. Following influenza injury and subsequent Alternaria alternata challenge, tuft cell-deficient mice also showed neutrophilic and ILC3 expansion. Together, these data identify a distal-airway tuft-cell-ILC2 circuit that helps maintain a balanced inflammatory environment in response to viral injury and aeroallergens.

molecular biology↗

Corepressor NCoR1-mediated regulation of mucin dynamics governs gut inflammation

Inflammatory bowel disease (IBD), comprising Ulcerative colitis (UC) and Crohns Disease, is a chronic relapsing immune-mediated inflammatory disorder of the gut. The intestinal mucus layer is a protective barrier that safeguards direct exposure of epithelium to luminal microbes and antigens. A prolonged disruption of the mucus layer may contribute to the development of IBD. Loss of mucin-producing goblet cells is a hallmark of UC. The underlying molecular mechanism controlling goblet regulation remains poorly understood. In the current work, we show a key role for NCoR1 (Nuclear corepressor 1) in goblet cell regulation. A specific downregulation of NCoR1 in intestinal crypts and goblet cells was observed in human UC and mice models. While NCoR1 was upregulated during goblet cell differentiation, inflammatory cues downregulated its expression. Experimental loss of NCoR1 resulted in exacerbated disease in a murine model of colitis, whereas its upregulation via Vitamin D led to a rescue. ChIP-seq led to the identification of KLF-16, a transcription factor, as a target of NCoR1. NCoR1 -KLF16 regulatory axis regulated key goblet cell proteins, including MUC2. Mechanistically, the regulation of MUC2 is modulated by the NCoR1-KLF16 axis, via mTOR signalling. In conclusion, this work shows a critical involvement of NCoR1-KLF16 in governing goblet cell function and intestinal homeostasis.

molecular biology↗

Deterministic retrieval recovers biomedical associations lost by language models

Biomedical research increasingly relies on expert-curated databases to connect diseases, genes, variants, phenotypes, pathways and therapeutics. Incomplete or irreproducible retrieval can distort interpretation, mechanistic inference, variant assessment or therapeutic prioritization despite an unchanged evidence base. Agentic natural-language-to-SQL (NL2SQL) systems and Model Context Protocol-enabled agents can autonomously retrieve evidence from biomedical databases, including Open Targets and the Highly Confident Drug-Target Database, in response to natural-language questions. However, they may truncate large result sets, miss records when terminology differs from database vocabulary and return different outputs across runs. We systematically quantify these failures and introduce BioChirp, a goal-directed autonomous system for reliable retrieval from structured biomedical databases, built on interpretation-execution separation. A coordinated language-model layer interprets intent and resolves database-field assignments, after which entity resolution maps user terms to database terminology. A deterministic Steiner-tree planner and executor then retrieve matching records without further language-model involvement. Across curated biomedical databases spanning more than one million associations, BioChirp retrieved thousands of records for exhaustive queries, whereas baseline agents returned at most a few hundred or failed. Across 70 queries, five runs and three BioChirp database backends, BioChirp achieved a median cross-run Jaccard similarity of 1.0. Across 910 database-question evaluations derived from expert-written BioASQ questions and spanning ten databases, BioChirp retrieved at least one database record in 85.4% of cases and produced a fully correct answer in 51.1% of cases, compared with 44.6% and 17.4% for agentic NL2SQL. BioChirp is publicly available at https://biochirp.iiitd.edu.in.

bioinformatics↗

Calibration of in-frame indel variant effect predictors for clinical variant classification

Insertions and deletions (indels) represent a substantial source of genetic variation in humans and are associated with a diverse array of functional consequences. Despite their prevalence and clinical importance, indels, particularly short in-frame indels, remain critically understudied compared to single nucleotide variants and are challenging to interpret clinically. While many computational predictors for missense variants have been rigorously evaluated and calibrated for clinical use, the clinical utility of tools for in-frame indels remains uncertain. To address this gap, we have calibrated in-frame indel prediction tools for clinical variant classification. We constructed a high-confidence dataset of in-frame indel variants ([≤] 50bp) from clinical and population databases and estimated the prior probability of pathogenicity of a rare in-frame indel observed in a disease-associated gene, and of an insertion and deletion separately. Using a previously developed statistical framework based on local posterior probabilities, we then established score thresholds for eight computational tools, corresponding to distinct evidence levels for pathogenic and benign classification according to ACMG/AMP guidelines. All in-frame indel predictors evaluated here reached multiple evidence levels of pathogenicity and/or benignity, demonstrating measurable clinical value. However, these models consistently exhibited lower performance levels compared to missense predictors, highlighting the need for improved computational approaches for indel classification.

bioinformatics↗

Myeloma and therapy reshape the bone marrow niche to durably constrain immune reconstitution and vaccine responsiveness

Infections are the most common cause of non-relapse mortality in multiple myeloma (MM), but the basis of persistent immune dysfunction is obscured by patient heterogeneity and complex treatment regimens, including autologous stem cell transplant (ASCT). We performed longitudinal multi-omic profiling of matched bone marrow and peripheral blood from MM patients across diagnosis, induction, ASCT, and recovery. We found the tumor imposes a compartment-specific immune program where the marrow exhibits metabolic and inflammatory changes that bias hematopoiesis and alter cytotoxic effector programs not mirrored in blood. Adaptive immune reconstitution is impaired up to two years post-ASCT. Half of patients fail to mount IgG responses to high-dose non-adjuvanted influenza vaccine, a defect overcome by the lipid nanoparticle (LNP) adjuvanted COVID mRNA vaccine, which elicited responses in all patients, supporting adjuvanted influenza vaccine strategies in MM. Together these findings define how myeloma and its treatment durably reshape immunity from the marrow outward. HighlightsO_LIMultiple Myeloma marrow and blood show opposing metabolic and inflammatory states C_LIO_LIInduction therapy selects durable myeloma plasma-cell transcriptional states C_LIO_LIB cell and follicular helper T deficits blunt antigen responses after transplant C_LIO_LICOVID-19 vaccination builds immune memory with variable responses to flu vaccination C_LI eTOCMultiple myeloma and its treatment leave a lasting imprint on the bone marrow niche. By profiling bone marrow and blood longitudinally at diagnosis, through induction, autologous transplant, and recovery, we show that marrow-local metabolic and inflammatory constraints persist and help explain why influenza vaccination often fails while mRNA vaccination succeeds.

cancer biology↗

Dysplastic Epithelial Repair Propagates Chronic Pathology Through the Paracrine Transformation of Pulmonary Fibroblasts

Severe lung injury promotes the ectopic accumulation of basal cells in the alveoli and the presence of these dysplastic epithelial cells are strongly associated with regions of pulmonary fibrosis (PF) in diseased lungs. Recent studies have identified a unique subset of "inflammatory" fibroblasts expressing pro-inflammatory genes, especially cytokines involved in monocyte recruitment, that are also enriched in disease and thought to contribute to the onset and progression of PF. Here we show that these two injury-induced cell types are intricately connected, in that dysplastic basal cells generate diffusible signals to robustly induce the inflammatory phenotype in pulmonary fibroblasts. Capitalizing on transcriptomic analysis, we identify the enriched inflammatory signaling pathways in treated fibroblasts and specifically demonstrate that IL-1 secreted by dysplastic basal cells is responsible for this fibroblastic transformation. IL-1 neutralization in vivo is sufficient to significantly reduce the inflammatory fibroblast burden in regions of alveolar bronchiolization, and the resolution of inflammatory fibroblasts in turn reduces CCR2+ immune cell recruitment to these areas. These results suggest dysplastic basal cells play an indirect role in chronic inflammation and fibrotic remodeling through the induction of a proinflammatory fibroblast phenotype and subsequent recruitment of immune cells, establishing a chronic wound healing microenvironment that prolongs localized pathologic remodeling.

cell biology↗

Spatiotemporal Variation in White-Matter Development Across Early Childhood

Early childhood development is scaffolded by rapid maturation of brain white matter structure, believed to support the emergence of cognitive and socioemotional functions. Previous whole-tract studies have suggested patterns of white matter development occurring along posterior-anterior, deep-superficial and inferior-superior axes. However, little is known as to whether these patterns are evident within tracts. Using longitudinal diffusion imaging data from 133 children (4-8 years; 76 females), the present work characterizes along-tract patterns of white matter development across association, commissural and projection bundles using fixel-based analyses of microstructure and macrostructure. Within long range association bundles, faster age-related changes were observed for segments adjacent to the visual cortices relative to segments located near association regions, supporting a sensorimotor-association axis of brain development. An inferior-superior pattern was found for projection tracts, with faster age-effects observed for segments near the brainstem. Lastly, while several association and commissural bundles exhibited faster maturation within central segments; indicative of a deep-superficial axis, effects were mixed between micro- and macrostructure, underscoring the unique developmental timing of these different fiber properties. Our findings provide evidence that within-tract white matter maturation unfolds along key spatiotemporal axes and suggests that increased spatial precision can advance our understanding of early childhood brain development.

neuroscience↗

Coronin1A regulates tumor microenvironment in colitis-associated colorectal cancer in a SUMO-dependent way

Inflammatory bowel disease (IBD), comprising Crohns disease and Ulcerative colitis, is a group of multifactorial illnesses with persistent gastrointestinal inflammation and a series of undesirable consequences. IBD patients have a three times higher risk of developing colitis-associated colorectal cancer (CAC). A higher mutational burden due to persistent inflammation acts as a driver of dysplasia and even tumorigenesis. While the pathological sequence is known, the molecular mechanisms underlying the transition from chronic inflammation to CAC remain largely elusive. Post-translational modification- SUMOylation plays an integral role in shaping gut inflammation as well as several forms of cancers, including sporadic colorectal cancer. In this study, the contribution of SUMOylation to CAC pathogenesis was characterized. In the AOM-DSS CAC mice model and human IBD patient specimens, SENP5, but not other deSUMOylases, shows an altered expression. Notably, both SENP5 expression dynamics and alterations in the SUMOylome occur in chronically inflamed and neoplastic colon tissues. SENP5 interactome analysis identified Coronin1A (Coro1A), an actin-binding protein predominantly expressed in immune cells. Coro1A also shows a state-specific, distinct expression pattern in the colon. Interestingly, in contrast to wild-type mice, Coro 1A knockout mice were resistant to polyp formation, with reduced cell proliferation, oncogene expression, and epithelial-to-mesenchymal transition (EMT) gene activation, and reduced extracellular matrix (ECM) development and fibrosis, suggesting its integral role in tumorigenesis. WT mice with chronically inflamed colons and polyps have a higher number of M2-like macrophages, with increased abundance of Coro1A, suggesting a role of Coro1A in modulating the tissue microenvironment toward a pro-tumorigenic state. Mechanistically, Coro1A physically interacts with TGF-{beta} RI and regulates TGF-{beta}-TGF-{beta} RI signalling endosome stability, thereby controlling TGF-{beta}-mediated macrophage polarization. Detailed in vitro experiments revealed stabilization of Coro 1A through its interaction with SUMOylated Raftlin protein. Overall, Coro 1A is necessary and sufficient for TGF-{beta} signalling, macrophage polarization, and tumorigenesis in CAC.

cancer biology↗

Coexistent PTEN and PIK3CA alterations hyperactivate mTORC1 signaling in endometrial cancers and cause their selective sensitivity to mTORC1 inhibition

In approximately half of endometrial carcinoma (EC), PTEN loss-of-function and activating PI3K mutants coexist. Unlike cells with either single mutation, PTEN/PIK3CA coexistent alterations result in elevated membrane phosphatidylinositol (3,4,5)-trisphosphate (PIP3) levels and mTORC1 hyperactivation, rendering PI3K or AKT inhibition ineffective in blocking mTORC1 activity and tumor growth. The bi-steric mTORC1 kinase inhibitor, RMC-6272, suppresses mTORC1 activity and cell growth by reducing protein translation and cell cycle progression. In vivo, RMC-6272, but not PI3K inhibitors, effectively suppressed mTORC1 and growth of EC PDXs with coexistent PTEN/PIK3CA lesions. These findings are consistent with a phase I trial of bi-steric mTORC1 inhibitor RMC-5552, showing anti-tumor activity in patients with EC. PDXs with KRAS co-mutations regrew after RMC-6272 treatment, which was prevented by the addition of the RAS(ON) multi-selective inhibitor RMC-7977. Overall, these data suggest that mTORC1 hyperactivation drives ECs with coexistent PTEN/PIK3CA mutations, explain the limited antitumor activity of PI3K and AKT inhibitors, and support clinical evaluation of mTORC1 inhibitors as potential therapy for EC. SignificanceWe have found the mechanistic consequences of PTEN/PIK3CA co-alterations in endometrial tumors and that these mutations result in a profound hyperactivation of mTORC1 signaling. Single mutant tumors are sensitive to PI3K inhibition but those with both mutations are insensitive to PI3K or AKT inhibition but are exquisitely dependent on mTORC1 kinase. This provides strong preclinical rationale for targeting mTORC1, alone or combined with RAS inhibition (in RAS co-mutant tumors), as an effective therapeutic strategy.

cancer biology↗

Histotripsy-initiated immune response synergizes with chemotherapy in a neuroblastoma murine model

High-risk neuroblastoma (NB) is a pediatric malignancy associated with metastases and an immunosuppressive tumor microenvironment. Standard-of-care treatments like chemotherapy are often ineffective, which motivates the investigation of adjuvant approaches. Histotripsy is a noninvasive focused ultrasound therapy that ablates tissue through the mechanical action of bubble clouds. In addition to disruption of the targeted tumor, non-targeted lesions exhibit growth delay after the histotripsy procedure. The primary hypothesis of this study was histotripsy-induced shifts in the tumor microenvironment will improve the response of metastatic NB to chemotherapy. Female A/J mice flanks were inoculated bilaterally with 1x10 Neuro-2a cells. Histotripsy was applied to one tumor (200-500 mm3), with or without concurrent administration of liposomal doxorubicin (LDOX). The contralateral tumor served as a model of non-targeted distal metastases. Following treatment, tumors were monitored indefinitely for growth, or assessed after 5-7 days with flow cytometry, single-cell RNA sequencing, and immunohistochemistry. Histotripsy alone delayed the growth of treated and contralateral tumors relative to controls (p = 0.01 and p < 0.0001, respectively) and increased CD8 T and CD11b+ cells (p < 0.05 for both comparisons). Further, NB cells in targeted and contralateral tumors exhibited a decrease in Myc expression and cell-cycle activity, and upregulation of interferon and apoptosis pathways. Histotripsy combined with LDOX had the longest delay in tumor growth (p < 0.01) and greatest expression of CD8 and MOMA staining. These findings indicate that histotripsy induces a systemic antitumor immune response that potentiates chemotherapy efficacy in this model of metastatic NB. SignificanceMechanical ablation with histotripsy drives systemic antitumor immunity, reshapes the tumor microenvironment, and enhances chemotherapy efficacy in a syngeneic model of metastatic, high-risk neuroblastoma.

cancer biology↗

Endogenous retroviral elements LTR8B and MER65 rewire PSG9regulation to control trophoblast syncytialization and pre-eclampsia risk

BackgroundUnderstanding the causes of the exceptional rate of evolution of the mammalian placenta is likely to aid the understanding of placental development and the aetiology of the human-specific pregnancy disorder pre-eclampsia (PE). As retroelements (REs) are often lineage-specific and known to be co-opted for placental functioning, here we consider the RE binding of GATA3 and DLX5, these transcription factors being dysregulated in PE, and their downstream consequences. MethodsMultiomics analyses identified the retroviral regulatory sequence LTR8B in the PSG gene array, as a contributor to expression diversification in the placenta. To characterize this genomic domain, we performed copy number variation analysis and whole-genome sequencing. Multiomics data was employed to identify loci that might act as an active chromatin loop boundary around the PSG region. CRISPR-Cas9 knockouts with aligned RNAseq and epigenetic mark data tested for trophoblast-specific cis-regulatory elements (CREs-enhancer and/or promoter sequences) of resulting loci. Functional assays were employed to characterize the phenotypic effects of a candidate locus. Structural analysis of PSG family members also identified an additional RE, MER65-int. RNA-seq and antibody staining was employed to consider polyadenylation and functional diversification. ResultsThe LTR8B CRE facilitates the binding of transcription factors (e.g., GATA3, DLX5, TFAP2A/C), resulting in a diversified PSG gene expression pattern within a primate-specific genomic region that exhibits high intraspecies variability. The LTR8B/PSG9 regulatory element influences other PSG family members. PSG9, unique among PSGs, produces both secreted and membrane-anchored isoforms, MER65-int providing alternative polyA signals, enabling the evolution of secreted PSG variants through the truncation of the ancestral CEACAM proteins transmembrane domain. The LTR8B/PSG9 locus regulates the differentiation of multinucleated trophoblasts (syncytialization) and, like chorionic gonadotropin and syncytin1, determines the identity of syncytiotrophoblasts. Notably, PSG9 is the most upregulated PSG in PE, with levels correlated with GATA3 and DLX5 levels. ConclusionsREs contribute to the structural and expression evolution of PSG genes, facilitating lineage-specific placental evolution. The LTR8B/PSG9 regulatory network plays a central role in syncytiotrophoblast differentiation. Given the association between DLX5/GATA3 dysregulation and elevated PSG9 levels, along with PSG9s expression in the first trimester, PSG9 shows potential as a predictive biomarker for PE.

developmental biology↗

Fast, accurate construction of multiple sequence alignments from protein language embeddings

Multiple sequence alignment (MSA) is a foundational task in computational biology, under-pinning protein structure prediction, evolutionary analysis, and domain annotation. Traditional MSA algorithms rely on pairwise amino acid substitution matrices derived from conserved protein families. While effective for aligning closely related sequences, these scoring schemes struggle in the low-identity "twilight zone." Here, we present a new approach for constructing MSAs leveraging amino acid embeddings generated by protein language models (PLMs), which capture rich evolutionary and contextual information from massive and diverse sequence datasets. We introduce a windowed reciprocal-weighted embedding similarity metric that is surprisingly effective in identifying corresponding amino acids across sequences. Building on this metric, we develop ARIES (Alignment via RecIprocal Embedding Similarity), an algorithm that constructs a PLM-generated template embedding and aligns each sequence to this template via dynamic time warping in order to build a global MSA. Across diverse benchmark datasets, ARIES achieves higher accuracies than existing state-of-the-art approaches, especially in low-identity regimes where traditional methods degrade, while scaling almost linearly with the number of sequences to be aligned. Together, these results provide the first large-scale demonstration of the power of PLMs for accurate and scalable MSA construction across protein families of varying sizes and levels of similarity, highlighting the potential of PLMs to transform comparative sequence analysis. Code availabilityhttps://github.com/Singh-Lab/ARIES

bioinformatics↗

Thioredoxin interacting protein (TXNIP), a redox regulator, mediates the RAPGEF3/4 signaling dependency in primary melanoma

Progression of cutaneous primary melanoma that arises from melanocytes leads to lethal metastatic disease. Molecular mechanisms that control the growth of primary melanoma in the skin and promote progression are not fully understood. Previously we showed that RAP guanine exchange factors EPAC1/2 (Exchange Protein Activated by cyclic AMP) promote the growth of primary melanoma and loss of dependency on EPACs is associated with metastatic progression. In this study, we show that EPACs are activated during malignant transformation of melanocytes, and chemical inhibition or genetic deletion of EPAC inhibits melanomagenesis in Braf/Pten mice. Low expression of EPAC mRNA and its effector RAP1-GTP protein in primary melanoma correlate with better recurrence-free survival. RNAseq analysis of matched primary and metastatic melanoma cells treated with an EPAC inhibitor showed that TXNIP, an important regulator of redox homeostasis, is a downstream effector of EPAC signaling. We also show that EPACs promote melanoma growth by regulating redox homeostasis and mitochondrial ROS through activation of mechanistic target of rapamycin complex 1 (mTORC1) that stabilizes hypoxia-inducible factor 1-alpha (HIF-1), a transcriptional activator of redox regulator TXNIP and glycolytic enzymes. Our data suggest that targeting mechanisms that melanoma cells employ to bypass EPAC dependency is a potential therapeutic approach. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=134 SRC="FIGDIR/small/696903v2_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@1967afaorg.highwire.dtl.DTLVardef@63b907org.highwire.dtl.DTLVardef@1089da4org.highwire.dtl.DTLVardef@a5b2ef_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Comparative Evaluation of Conventional Inorganic Fertilization and Sesbania rostrata Green Manuring on Soil Properties and the Growth and Development of Oryza sativa L. Pant Basmati 1

To assess the impacts of conventional and organic nutrient management techniques on growth, productivity, sustainability, and soil health in the Basmati rice (Oryza sativa L.) cultivar Pant Basmati 1, a two-year field experiment was carried out during the Kharif seasons of 2023 and 2024. Crop duration remained stable across management methods, as illustrated by phenological variables such as panicle initiation (58-62 days), blooming (84-88 days), and maturity (106-111 days) that were not significantly affected by fertilizer source. Conventional fertilizer supported superior growth at later stages, while organic management produced greater plant height at early growth phases. While the leaf area index and dry matter accumulation were consistently higher under conventional management because of the quick availability of nutrients, tiller density remained similar across treatments (363-411 m-{superscript 2}). Despite statistically significant variations, chlorophyll a and b quantities peaked under organic inputs at 60 DAT. Higher biological and grain yields were obtained with conventional fertilization; however, yield variations between systems were generally insignificant over time. As soil fertility stabilized, organic management notably increased the harvest index in the second year, indicating improved assimilate partitioning. The findings show that organic nutrient management can provide benefits in terms of resource efficiency and environmental sustainability while maintaining yield parity with conventional systems during the early conversion phase. Organic management techniques improve soil quality. Compared with to conventional methods, organic management practices were found to have higher soil macro and micronutrient status, water-holding capacity, aggregate stability, and soil enzyme activity (DHA and acid & alkaline phosphatase). These results show that organic Basmati rice cultivation is a feasible and sustainable alternative to traditional nutrient management, even though it may take longer to reach maximum yield.

plant biology↗