S25D8RVYD / 2026
Kayla G. Retallick-Townsley, Seoyeon Lee, Sarah E. Williams et al. · 10.1038/s41467-026-77114-x
The immune environment influences neurodevelopment and subsequent clinical trajectories for psychiatric outcomes in childhood and adolescence. Yet it remains unclear if the impact of maternal and fetal immune activation varies with distinct polygenic risk profiles. Therefore, here we catalog genotype and environment (GxE) interactions, contrasting allele-specific regulatory activity between inflammatory cues. We report a cue-specific neuronal massively parallel reporter assay (MPRA) of 152 loci from genome-wide association studies (GWAS) of ten brain traits/disorders, empirically dissecting the impact of interleukin-6 (IL-6) and interferon-alpha (IFNα) on transcriptional activity. In human induced pluripotent stem cell (hiPSC)-derived glutamatergic neurons, 1,156 active candidate regulatory risk sequences (MPRA-active CRSs) are resolved, including 267 with variant-specific effects (MPRA-emVars) and 61 with variant-by-cytokine interaction effects (interaction MPRA-emVars). Broadly, neuronal immune-mediated regulatory activity is associated with differences in transcription factor binding and chromatin accessibility, the gene targets of which show pleiotropic enrichments for brain, metabolic, and immune disorders. Dynamic genetic regulation mediates neuroimmune effects, informing our understanding of the genomics of psychiatric and neurological traits, mechanisms governing pleiotropy across disorders, and how immune mechanisms mediate genetic risk.
S6UTSE4JZ / 2026
Max Trauernicht, Vinícius H. Franceschini-Santos, Hatice Yücel et al. · 10.1038/s44320-026-00240-7
Transcription factors (TFs) are central to gene regulation and play critical roles in development, cellular homeostasis and disease. The ability to accurately measure TF activity is essential to understanding how TFs respond to signals and regulate target genes. In one commonly used approach, activities of TFs are computationally inferred from genome-wide chromatin accessibility data (ATAC-seq). However, it has remained unclear how well these inferences reflect actual regulatory activity of TFs. An alternative approach employs a collection of synthetic reporters that are designed to each probe the regulatory activity of a single TF. In this study, we systematically compared TF activities as inferred by ATAC-seq with those measured by multiplexed reporters, across diverse perturbations known to alter specific TF activities. We observed considerable overlap between the two methods, but also notable discrepancies. Our findings suggest that reporter assays and chromatin-based inference capture distinct aspects of TF function: reporter assays are more sensitive to signal-responsive TFs, while ATAC-seq better detects chromatin-modifying TFs.
S9AU3WOKK / 2026
Darius Ramkhalawan, Justin Koesterich, Fahim Rejanur Tasin et al. · 10.1101/gr.281888.126
Adolescent idiopathic scoliosis (AIS) is a common pediatric musculoskeletal disorder characterized by lateral spinal curvature, often leading to chronic pain and deformity. While a significant genetic component to AIS is recognized, the functional impact of most associated genetic variants, particularly those in noncoding regions, remains largely unknown. Using massively parallel reporter assays, we examined the regulatory activity of 1,664 variants in linkage disequilibrium with 26 AIS lead variants identified through genome-wide association studies (GWAS). Candidate regulatory sequences containing the reference or alternative alleles were tested in two human chondrocyte cell lines, TC28a2 and SW1353, as chondrocytes are a major cell type implicated in AIS pathogenesis. We identified 92 variants with significant allele-specific regulatory activity, 79 of which are predicted to disrupt transcription factor binding sites, often correlating with their observed regulatory effect. Notably, we validate rs9496392, a single-nucleotide variant near the ADGRG6 locus, which shows consistent differential regulatory activity in both cell lines. ADGRG6 is a key regulator of cartilage homeostasis, and its cartilage-specific knockout in mice results in a scoliosis-like phenotype. The AIS risk allele of rs9496392 (T) is predicted to strongly disrupt several TFBSs, including SP1. This study provides a foundational catalog of functional AIS-associated regulatory variants active in chondrocytes, offering crucial insights into the perturbed gene regulatory networks in AIS. These findings lay the groundwork for identifying biomarkers and potential therapeutic targets for this complex childhood disease.
S7KSH5QDC / 2026
Giovanna Weykopf, Wendy A. Bickmore, Simon C. Biddie et al. · 10.1371/journal.pgen.1012222
Common genetic variants contribute to risk for complex human diseases. However, despite thousands of associations, variants modulating disease risk and their functional impact remain largely unknown. This includes SARS-CoV-2 infection, where outcomes range from asymptomatic to fatal. Most genetic risk variants associated with COVID-19 disease, identified through genome wide association studies, are located in the non-coding genome and may function by altering gene expression in disease-relevant cells and tissues. To address this at scale, we tested >4800 severe COVID-19-associated variants to determine the impact of individual variants and variant combinations on regulatory activity using Self-Transcribing Active Regulatory Region sequencing, a massively-parallel reporter assay. Focusing on variants that may have their impact in the lung, in a lung epithelial cell line (A549) we identify 166 variants within active sequences, of which 29 modulate activity allele-specifically. Evaluating variant combinations, we observe both additive and non-additive effects on regulatory activity. We employ state-of-the-art deep learning models to interpret allele-specific variant effects on regulatory activity and endogenous genomic features. Our work provides a set of prioritised severe COVID-19-associated variants that modulate regulatory activity in lung epithelial cells, candidate transcription factors, and candidate target genes with potential to be disease modifying.
S3G8Y80IC / 2026
Julia Rühle, Robert Frömel, Aina Bernal Martinez et al. · 10.1186/s13059-026-04186-9
Background: Cell state-specific gene expression programs emerge from the interplay between cis-regulatory elements (CREs), such as enhancers, and transcription factors (TFs). Massively parallel reporter assays (MPRAs) have enabled large-scale dissection of CRE function, but bulk approaches cannot resolve cell state specificity on continuous trajectories of cellular differentiation, and existing single-cell MPRAs are not readily applicable to primary cell differentiation models. Results: Here, we develop a single-cell lentiviral Massively Parallel Reporter Assay (sc-lentiMPRA) that overcomes these limitations and enables parallel quantification of enhancer activity and cellular transcriptome. Applying sc-lentiMPRA in blood stem differentiation, we profile the activity and specificity of ~160 fully synthetic enhancers with controlled motif composition and affinities across ~190,000 single cells. Focusing on Trp53 and Cebpa, we show that enhancers with high and low affinity motifs differ qualitatively and quantitatively in their responses to TF expression gradients. For Trp53, low-affinity motifs exhibit near-linear correlation with TF expression, whereas high-affinity motifs show reduced sensitivity to TF levels. In contrast, Cebpa-associated enhancers display non-linear behaviors. Conclusions: Together, sc-lentiMPRA establishes a powerful framework for systematically relating enhancer architecture and TF expression to regulatory output at single-cell resolution during cellular differentiation.
S0RLHNEG6 / 2026
Colin J. Shew, Gulhan Kaya, Sean P. McGinty et al. · 10.1101/gr.281526.125
Human-specific segmental duplications (HSDs) contain millions of base pairs of sequence unique to the human genome, including genes that shape neurodevelopment. Despite their young age (<6 million years), HSD genes exhibit widespread regulatory divergence, with paralog-specific expression patterns documented across a variety of tissues and cell types. Using long-read expression and epigenomic data, we show that human-specific paralogs tend to have lower activity than the shared, ancestral ones. To systematically characterize the cis-regulatory elements (CREs) within HSDs and understand patterns of regulatory change in recently evolved gene families, we conduct a massively parallel reporter assay of 7760 human duplicated and chimpanzee orthologous sequences in lymphoblastoid (GM12878) and neuroblastoma (SH-SY5Y) cell lines. A large proportion (14%–24%) of sequences exhibit differential activity relative to the chimpanzee ortholog (or between human paralogs), mostly with small fold-differences. Combining measured activity levels across all assayed sequences, predicted differences in cis-regulatory activity correlate with mRNA levels in SH-SY5Y. Differentially active CREs validated for CHRFAM7A, HYDIN2, and SRGAP2C may contribute to paralog-specific expression patterns and thereby to human-specific traits. Although we identify some changes in CRE activity within duplicated regions, consideration of adjacent, unique sequences suggests a larger contribution from genome positional effects. In all, this work shows that functional divergence of duplicated CREs contributes moderately to regulatory divergence of HSD genes and uncovers enhancers that are candidate drivers of human-specific regulatory patterns.
S7Z1TYV05 / 2026
Tom Röschinger, Heun Jin Lee, Rosalind Wenshan Pan et al. · 10.1101/2025.05.13.653802
All cells respond to changes in both their internal milieu and the environment around them through the regulation of their genes. Despite decades of effort, there remain huge gaps in our knowledge of both the function of many genes (the so-called y-ome) and how they adapt to changing environments via regulation. Here we describe a joint experimental and theoretical dissection of the regulation of a broad array of more than 100 biologically interesting genes in E. coli across 39 diverse environments, enabling us to identify the binding sites and transcription factors that mediate regulatory control. Using a combination of mutagenesis, massively parallel reporter assays, mass spectrometry, and tools from information theory and statistical physics, we go from complete ignorance of a promoter’s environment-dependent regulatory architecture to a quantitative description of its binding sites, candidate transcription factors that bind them where identifiable, and the conditions under which they act. As proof of principle of the biological insights to be gained from such a study, we chose a combination of genes from the y-ome, toxin-antitoxin pairs, and genes hypothesized to be part of regulatory modules; we discovered a host of new insights into their underlying regulatory landscape and resulting biological function. We highlight discoveries for y-ome genes, including transcription start sites and transcription factor binding sites at base-pair resolution, and their dependence on growth conditions.
S0BBCQFXK / 2026
Yingbo Jia, Chu-Yen Chen, Bo Zhu et al. · 10.64898/2025.12.08.693012
Synthetic enhancers with high specificity are crucial for therapeutic gene control. However, experimental screens and machine learning-guided design typically require context-specific datasets, limiting generalizability. Because transcription factor (TF) activity reflects cellular state, TF-responsive enhancer libraries offer a universal starting point. Here, we developed TREND (transcription factor-responsive enhancer discovery), a massively parallel reporter assay of ~2.7 million enhancer-barcode constructs representing 57,715 designs. TREND covers 1,068 motif-annotated proteins, including 729 confirmed TFs across 49 DNA-binding domain families. Applied to ovarian cancer, TREND identified enhancers that discriminate cancer from normal epithelial cells. These enhancers enabled protein-interaction-based AND-gate circuits with reduced OFF-state leakage and amplified ON-state output, driving tumor-restricted expression of combinatorial immune effectors and robust antitumor responses in murine ovarian cancer models. TREND also identified T-cell activation-responsive enhancers with greater inducibility and lower basal activity than conventional NFAT-motif-based elements. Together, TREND provides a generalizable framework for context-specific enhancer discovery and therapeutic gene regulation.
S295UP2Y5 / 2026
Lianne B. Cohen, Tamara Hadzic, Caitlin Sauer et al. · 10.1101/gr.281432.125
To defend against microbes, animals regulate a complex immune response. The Drosophila innate immune system deploys a large transcriptional induction of signaling proteins, antimicrobial effectors, and other critical immune factors. This transcriptional response is encoded in enhancers, cis-regulatory sequences that modulate gene expression by binding transcription factors (TFs). Although enhancers and transcription factor binding sites (TFBSs) have been identified for several immune responsive genes in Drosophila, most enhancers that regulate immune-induced genes are unknown. By identifying enhancers, we can understand how their composition controls expression and contributes to infection outcome. We employ self-transcribing active regulatory-region sequencing (STARR-seq) in a hemocyte-like cell line to identify immune-specific enhancers across the D. melanogaster genome and perform ATAC-seq in hemocytes extracted from adult flies to assess the chromatin state of these enhancers before and after immune stimulus. We identify hundreds of enhancers responsive to IMD stimulation, one of the two primary immune signaling pathways in Drosophila. As expected, immune enhancers are enriched for motifs of Relish, an NF-kB factor, and Kay/Jra, a bZip heterodimer pair, involved in the Imd and JNK pathways respectively, compared with enhancers active in unstimulated cells. However, when grouping enhancers by their target gene's expression timing or functional role or by the enhancers’ chromatin accessibility pre- or post-stimulus, different groups of TFBS motifs are enriched, suggesting distinct regulatory logic for different parts of the immune response. Identification and characterization of the diverse array of enhancers that regulate the innate immune response expand our understanding of how animals fight infections.
S6DU50JWV / 2026
Sarah K. Koester, Kristina Sakers, Gareth M. Rurak et al. · 10.64898/2026.04.27.721172
RNA localization and local translation are essential mechanisms to fine-tune spatiotemporal gene expression in the nervous system. However, efficiently assessing the thousands of possible sequence determinants of RNA localization is a challenge, particularly for cell types that only reach morphological maturity in vivo. Here, we developed an in vivo Massively Parallel Reporter Assay (MPRA), termed Synaptoneurosomal (SN)-MPRA to enable identification of sequence determinants of mRNA localization and local translation, and applied this to astrocytes. We evaluated multiple models of RNA localization for two locally translated astrocyte mRNAs, Glt1 and Sparc, including increased transcript abundance, “zipcode” elements, and RNA secondary structure. Our results establish a high-throughput in vivo framework for identifying cis-regulatory sequences driving RNA localization and local translation, and suggest astrocytes use diverse mechanisms to regulate subcellular gene expression. More broadly, SN-MPRA offers a versatile platform to study RNA localization in vivo, where biological context and intercellular interactions are preserved.
S3QZWSI06 / 2026
Anirban Sarkar, Alejandra Duran, Yiyang Yu et al. · 10.1101/2024.05.23.595630
Designing regulatory DNA with tunable and context-specific activity is a major goal in biotechnology and medicine. Deep generative models offer a promising route for sequence design, yet it remains unclear whether synthetic sequences faithfully recapitulate the motif organization and functional specificity of natural regulatory DNA. Here we present DNA Discrete Diffusion (D3), a generative model that designs regulatory DNA through an iterative nucleotide-substitution process. Across computational benchmarks, D3 improves regulatory sequence generation relative to matched diffusion baselines, producing sequences that more closely match target activity, activity distributions, and sequence composition. In K562 lentiMPRA experiments, D3-designed sequences retained measurable regulatory activity and more closely recapitulated the activity distribution of genomic regulatory sequences than matched diffusion baselines. D3 performs robustly with limited training data and generates sequences informative enough to improve predictive models when labeled data are scarce. When trained without activity labels on task-specific regulatory sequence sets, D3 learns frozen sequence representations that are predictive of enhancer activity and compare favorably to several off-the-shelf genomic language model embeddings. Analysis of the sampling process identifies reproducible phases of sequence exploration, compositional refinement, and motif-associated convergence, providing an interpretable view of how D3 constructs regulatory sequences. These results establish D3 as a practical framework for designing synthetic regulatory DNA and studying sequence features associated with context-specific regulatory activity.
S1CQK2QFM / 2026
Yonatan Shapira, Florian Noack, Silvia Vangelisti et al. · 10.1101/gad.353090.125
During cortical development, neural stem cells (NSCs) combine self-renewal with the sequential production of different subtypes of projection neurons as well as glia cells. How the NSC epigenome accommodates this over time remains unresolved. Here, we address this gap by multimodal epigenomic profiling of mouse cortical development across six time points and five embryonic days. Single-cell gene expression and temporal modeling reveal that NSC self-renewal is not homeostatic, showing progressively stronger astrocytic preference over time. Chromosome accessibility, DNA methylation, and Hi-C show that this process involves major reorganization of the NSC epigenome. A model combining transcription factor motif affinities with epigenetic features, as well as integration of the results with a reporter assay in vivo, show that activation of the NSC neuronal fate regulatory program may be affected by a changing epigenome. Collectively, our findings uncover temporal epigenomic reprogramming that underlies the evolving differentiation potential of NSCs, providing insights into the intrinsic and extrinsic mechanisms that pattern cortical lineages.
Each experiment has a processed table with documented columns. Table structures and measurements vary between experiments. About the database