Adipose-resident T cells play a crucial role in the development of obesity-induced insulin resistance. However, the specific mechanisms, particularly those involving non-immune cytokines, remain unclear. Here, we report significantly elevated levels of sclerostin domain-containing protein 1 (SOSTDC1) in individuals with type 2 diabetes (T2D), showing positive correlations with fasting glucose and HbA1c. T cell-specific Sostdc1-deficient mice exhibit resistance to age-induced adipose lipid accumulation and glucose dysregulation at 12 months and protect against obesity-induced insulin resistance without affecting proinflammatory macrophage infiltration or adipose inflammation. Mechanistically, SOSTDC1 disrupts the lipid balance in adipocytes by promoting lipogenesis and inhibiting lipolysis through the LRP5/6-β-catenin pathway. Furthermore, T cell receptor (TCR) signaling significantly amplifies SOSTDC1 secretion in CD4 T cells. In summary, our study uncovers an additional mechanism by which T cells contribute to obesity and insulin resistance, suggesting that inhibiting SOSTDC1 could be a promising immunotherapeutic strategy for metabolic disorders.

Evolutionary studies of wild and domestic organisms have yielded fascinating discoveries, while the species diversity and the domestication of ducks remain unclear. Here, we assembled eight chromosome-level Anas genomes, combined with the Pekin duck genome, to investigate Anas evolution and domestication. We found that, compared to autosomes, the Z chromosome was less affected by introgression and exhibited relatively stable local phylogenies. From the Z chromosome perspective, we proposed that the speciation of Anas platyrhynchos and Anas zonorhyncha was accompanied by continuous female-biased gene flow and remodeled duck domestication history. Moreover, we constructed an Anas pan-genome and identified several differentiated structural variations (SVs) between domestic and wild ducks. These SVs likely regulate their neighboring genes (i.e., GHR and FER), which represented the promising "domestication genes." Furthermore, a long terminal repeat (LTR) retrotransposon burst was found to have accelerated duck domestication, specifically contributing to functional shifts of the notable MITF and IGF2BP1 genes. These findings presented a live example for understanding animal evolutionary processes.

NEUROD1 (ND1)-induced astrocyte-to-neuron (AtN) conversion shows promise for treating neurological disorders. To gain insight into the molecular mechanisms of neuronal reprogramming, we established an in vitro system using primary cortical astrocyte cultures from postnatal rats and employed single-cell and multiomics sequencing. Our findings indicate that the initial cultures primarily consisted of immature astrocytes (ImAs), with potentially a minor presence of radial glial cells. The ImAs initially went through an intermediate state, activating both astrocyte and neural progenitor genes. Subsequently, they mimic in vivo neurogenesis to acquire mature neuronal characteristics. We show that ND1 acted as a pioneer factor that reshapes the chromatin landscape of astrocytes to that of neurons. This restructuring promotes the expression of neurogenic genes via inducing H3K27ac modification. Through integrative analysis of various ND1-induced neuronal specification systems, we identified 25 ND1 targets, including Hes6, as key regulators. Thus, our work highlights the key role of ND1 and its downstream regulators in neuronal reprogramming.

Hypoxia-induced metabolic reprogramming is closely linked to breast cancer progression. Through transcriptomic analysis, we identified PRMT1 as a direct target of hypoxia-inducible factor 1α (HIF1α) under hypoxic conditions in breast cancer cells. In turn, PRMT1 enhances the expression of HIF1α-driven glycolytic genes. Mechanistically, PRMT1 methylates HIF2β at arginine 42, facilitating the formation, chromatin binding, and the transcriptional activity of the HIF1α/HIF2β heterodimer. Genetic and pharmacological inhibition of PRMT1 suppresses HIF2β methylation, HIF1α/HIF2β heterodimer formation, chromatin binding, glycolytic gene expression, lactate production, and the malignant behaviors of breast cancer cells. Moreover, combination treatment with iPRMT1, a PRMT1 inhibitor, and menadione, an HIF1α/P300 interaction inhibitor, demonstrates synergistic effects in suppressing breast tumor growth. Clinically, PRMT1 and PRMT1-mediated HIF2β methylation were significantly elevated in breast tumors compared with adjacent normal tissues. In conclusion, our findings reveal the critical role of PRMT1-mediated arginine methylation in glycolytic gene expression, metabolic reprogramming, and breast tumor growth.

Memory lymphocytes are durable cells that persist in the absence of antigen, but few human B cell subsets have been characterized in terms of durability. The relative durability of eight non-overlapping human B cell sub-populations covering 100% of all human class-switched B cells was interrogated. Only two long-lived B cell populations persisted in the relative absence of antigen. In addition to canonical germinal center-derived switched-memory B cells with an IgDCD27CXCR5 phenotype, a second, non-canonical, but distinct memory population of IgDCD27CXCR5 DN1 B cells was also durable, exhibited a unique TP63-linked transcriptional and anti-apoptotic signature, had low levels of somatic hypermutation, but was more clonally expanded than canonical switched-memory B cells. DN1 B cells likely evolved to preserve immunological breadth and may represent the human counterparts of rodent extrafollicular memory B cells that, unlike canonical memory B cells, can enter germinal centers and facilitate B cell and antibody evolution.

Immune memory is essential for the effectiveness of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination. In the current context of the pandemic, with a diminished vaccine efficacy against emerging variants, it remains crucial to perform long-term studies to evaluate the durability and quality of immune responses. Here, we examined the antibody and memory B-cell responses in a cohort of 113 healthcare workers with distinct exposure histories over a 3-year period. Previously infected and naive participants developed comparable humoral responses by 17 months after receiving a full three-dose mRNA vaccination. In addition, both maintained a substantial SARS-CoV-2-reactive memory B-cell pool, associated with a lower incidence of breakthrough infections in naive participants. Of note, previously infected participants developed an expanded SARS-CoV-2-reactive CD27CD21 atypical B-cell population that remained stable throughout the follow-up period. Thus, previous SARS-CoV-2 infection differentially imprints the memory B-cell compartment without compromising the development of long-lasting humoral responses.

Some pathogen-derived effectors reprogram mRNA splicing in host plants to regulate plant immune responses. Whether effectors from Exserohilum turcicum, which causes northern corn leaf blight (NLB), interfere with RNA splicing remains unknown. We identify that the secreted protein EtEC81 (Exserohilum turcicum effector 81) modulates the alternative splicing (AS) of maize (Zea mays) pre-mRNAs and negatively regulates the pathogenicity of E. turcicum. EtEC81 physically interacts with MAIZE EtEC81-INTERACTING PROTEIN 1 (ZmEIP1), which associates with maize spliceosome components, modulates AS in host cells, and positively regulates defense responses against E. turcicum. Transcriptome analysis identifies 119 common events with altered AS in maize plants transiently overexpressing ZmEIP1 or EtEC81, suggesting that these factors cause the misregulation of cellular activities and thus induce immune responses. Together, our results suggest that the EtEC81 effector targets ZmEIP1 to reprogram pre-mRNA splicing in maize. These findings provide a mechanistic basis and potential target gene for preventing NLB.

Plant lipids are an essential energy source for diets and are a sustainable alternative to petroleum-based fuels and feedstocks. Fatty acid breakdown during seed germination is crucial for seedling establishment but unexpected during seed filling. Here, we demonstrate that the simultaneous biosynthesis and degradation of fatty acids begins early and continues across all phases of oil filling and throughout the photoperiod. Tests in camelina, rapeseed, and an engineered high-oil tobacco line confirmed that concomitant synthesis and breakdown in oil-producing tissues over development is the rule rather than the exception. Furthermore, we show that transgenics, designed to elevate fatty acid biosynthesis, failed to achieve anticipated increases in storage lipid levels due to increased degradation, potentially explaining the underperformance of engineered lines compared to expectations more generally.

The NAIP/NLRC4 inflammasome plays a pivotal role in the defense against bacterial infections, with its in vivo physiological function primarily recognized as driving inflammation in immune cells. Acute lung injury (ALI) is a leading cause of mortality in sepsis. In this study, we identify that the NAIP/NLRC4 inflammasome is highly expressed in both macrophages and pulmonary fibroblasts and that pyroptosis of these cells plays a critical role in lung injury. Mice challenged with gram-negative bacteria or flagellin developed lethal lung injury, characterized by reduced blood oxygen saturation, disrupted lung barrier function, and escalated inflammation. Flagellin-induced lung injury was protected in caspase-1 or GSDMD-deficient mice. These findings enhance our understanding of the NAIP/NLRC4 inflammasome's (patho)physiological function and highlight the significant role of inflammasome activation and pyroptosis in ALI during sepsis.

Cisplatin (CDDP) is a widely used chemotherapy drug for treating various solid tumors. However, resistance to CDDP significantly hampers patient outcomes. This study reveals that protein arginine methyltransferase (PRMT)5 methylates METTL3 at the R36 residue (METTL3-R36me2), which is crucial for CDDP resistance in ovarian cancer (OC) cells. Following CDDP exposure, MST4 is transactivated by nuclear factor-erythroid 2-related factor 2 (NRF2), a key regulator of antioxidant responses. MST4 stimulates PRMT5's methyltransferase activity and promotes its interaction with METTL3 via phosphorylation at Ser439 and Ser463, resulting in increased levels of METTL3-R36me2 and mRNA methylation at the N6 position of adenosine (mA). The METTL3-R36me2 is recruited to DNA damage sites to promote RAD51 recruitment for homologous recombination (HR)-mediated double-strand break repair (DSBR) and enhance CDDP resistance. Importantly, targeting METTL3-R36me2 through inhibition of PRMT5 or METTL3 disrupts HR-DSBR and augments the cytotoxic effects of CDDP in ovarian tumor xenografts. Therefore, we conclude that METTL3-R36me2 represents a viable therapeutic target for overcoming CDDP resistance in OC.

Antibody effector functions contribute to the immune response to pathogens and can influence the efficacy of antibodies as therapeutics. To date, however, there is limited information on the molecular parameters that govern fragment crystallizable (Fc) effector functions. In this study, using AI-assisted protein design, the influences of binding kinetics, epitope location, and stoichiometry of binding on cellular Fc effector functions were investigated using engineered HIV-1 envelope as a model antigen. For this antigen, stoichiometry of binding was found to be the primary molecular determinant of FcγRIIIa signaling, antibody-dependent cellular cytotoxicity, and antibody-dependent cellular phagocytosis, while epitope location and antibodybinding kinetics, at least in the ranges investigated, were of no substantial impact. These findings are of importance for informing the development of vaccination strategies against HIV-1 and, possibly, other viral pathogens.

When host cells are infected with coronaviruses, the first viral protein produced is non-structural protein 1 (Nsp1). This protein inhibits host protein synthesis and induces host mRNA degradation to enhance viral proliferation. Despite its critical role, the mechanism by which Nsp1 mediates cellular mRNA degradation remains unclear. In this study, we use cell-free translation to address how host mRNA stability is regulated by Nsp1. We reveal that SARS-CoV-2 Nsp1 binding to the ribosome is enough to trigger mRNA degradation independently of ribosome collisions or active translation. MERS-CoV Nsp1 inhibits translation without triggering degradation, highlighting mechanistic differences between the two Nsp1 counterparts. Nsp1 and viral mRNAs appear to co-evolve, rendering viral mRNAs immune to Nsp1-mediated degradation in SARS-CoV-2, MERS-CoV, and Bat-Hp viruses. By providing insights into the mode of action of Nsp1, our study helps to understand the biology of Nsp1 better and find strategies for therapeutic targeting against coronaviral infections.

Building synaptic connections requires coordinating a host of cellular activities from cell signaling to protein turnover, placing a high demand on intracellular communication. Membrane contact sites (MCSs) formed between organelles have emerged as key signaling hubs for coordinating diverse cellular activities, yet their roles in the developing nervous system remain obscure. We investigate the in vivo function of the endoplasmic reticulum (ER) MCS tethering and lipid-transfer protein PDZD8, which was recently linked to intellectual disability, in the nervous system. We find that PDZD8 is required for activity-dependent synaptic bouton formation in multiple paradigms. PDZD8 is sufficient to drive excess synaptic bouton formation through an autophagy-dependent mechanism and required for synapse development when autophagy is limited. PDZD8 accelerates autophagic flux by promoting lysosome maturation at ER-late endosome/lysosome MCSs. We propose that PDZD8 functions in the nervous system to increase autophagy during periods of high demand, including activity-dependent synaptic growth.

Nuclear pore complexes (NPCs) are channels that control access to the genome. The number of NPCs that cells assemble varies between different cell types and in disease. However, the mechanisms regulating NPC formation in mammalian cells remain unclear. Using a genome-wide small interfering RNA (siRNA) screen, we identify translation-related factors, proteasome components, and the CCR4-NOT complex as top regulators of NPC assembly and numbers. While inhibition of ribosomal function and protein translation reduces NPC formation, blocking protein degradation or CCR4-NOT function increases NPC numbers. We demonstrate that CCR4-NOT inhibition raises global mRNA levels, increasing the pool of nucleoporin mRNAs available for translation. Upregulation of nucleoporin complexes in CCR4-NOT-inhibited cells allows for higher NPC formation, increasing total NPC numbers in normal and cancer cells. Our findings uncover that nucleoporin mRNA stability and protein homeostasis are major determinants of NPC formation and highlight a role for the CCR4-NOT complex in negatively regulating NPC assembly.

Zika virus (ZIKV) vertical transmission results in devastating congenital malformations and pregnancy complications; however, the specific receptor and host factors facilitating ZIKV maternal-fetal transmission remain elusive. Here, we employ a genome-wide CRISPR screening and identify multiple placenta-intrinsic factors modulating ZIKV infection. Our study unveils that hepatitis A virus cellular receptor 1 (HAVCR1) serves as a primary receptor governing ZIKV entry in placental trophoblasts. The GATA3-HAVCR1 axis regulates heterogeneous cell tropism in the placenta. Notably, placenta-specific Havcr1 deletion in mice significantly impairs ZIKV transplacental transmission and associated adverse pregnancy outcomes. Mechanistically, the immunoglobulin variable-like domain of HAVCR1 binds to ZIKV via domain III of envelope protein and virion-associated phosphatidylserine. Proteomic profiling and function analyses reveal that AP2S1 cooperates with HAVCR1 for ZIKV internalization through clathrin-mediated endocytosis. Overall, our work underscores the pivotal role of HAVCR1 in mediating ZIKV vertical transmission and highlights a therapeutic target for alleviating congenital Zika syndrome.

Suneil Koliwad (S.K.) and Martin Valdearcos (M.V.) spoke with Cell Reports about their scientific journeys leading to their recent paper investigating the role of microglia in shaping blood glucose homeostasis. They discuss the challenges and future directions of their work and share their publishing experience.

Hepatitis B infection can lead to liver fibrosis and hepatocellular carcinoma (HCC). Despite antiviral therapies, some patients still develop HCC. This study investigates hepatitis B virus (HBV)-induced hepatocyte-hepatic stellate cell (HSC) crosstalk and its role in liver fibrosis and HCC. Using MYC-driven liver cancer stem cell organoids, HCC-patient-derived xenograft (PDX) models, and HBV replication models, this study reveals that HBV transcription affected hepatocyte development, activated the DNA repair pathway, and promoted glycolysis. HBV activated nicotinamide phosphoribosyltransferase (NAMPT) through DNA damage receptor ATR. NAMPT-insulin receptor (INSR)-mediated hepatocyte-HSC crosstalk caused HSCs to develop a myofibroblast phenotype and activated telomere maintenance mechanisms via PARP1 multisite lactylation. Inhibition of the ATR-NAMPT-INSR-PARP1 pathway effectively blocks HBV-induced liver fibrosis and HCC progression. Targeting this pathway could be a promising strategy for chronic HBV infection management.

Although the gut microbiota is known to act as a bridge between dietary nutrients and the body's energy needs, the interactions between the gut microbiota, host energy metabolism, and exercise capacity remain uncertain. Here, we characterized the gut microbiota ecosystem in a cohort of healthy normo-weight humans with highly heterogeneous aerobic exercise capacities and closely related body composition and food habits. While our data support the idea that the bacterial ecosystem appears to be modestly altered between individuals with low-to-high exercise capacities and close food habits, we report that gut bacterial α diversity, density, and functional richness are significantly reduced in athletes with very high exercise capacity. By using fecal microbiota transplantation, we report that the engraftment of gut microbiota from athletes with very high exercise capacity improves insulin sensitivity and muscle glycogen stores into transplanted mice, which highlights promising therapeutic perspectives in fecal transplantation from human donors selected based on exercise capacity traits.

The clustering of multiple transcription factor binding sites (TFBSs) for the same TF has proved to be a pervasive feature of cis-regulatory elements in the eukaryotic genome. However, the contribution of binding sites within the homotypic clusters of TFBSs (HCTs) to TF binding and target gene expression remains to be understood. Here, we characterize the CHD4 enhancers that harbor unique functional ZNF410 HCTs genome wide. We uncover that ZNF410 controls chromatin accessibility and activity of the CHD4 enhancer regions. We demonstrate that ZNF410 binds to the HCTs in a collaborative fashion, further conferring transcriptional activation. In particular, three ZNF410 motifs (sub-HCTs) located at 3' end of the distal enhancer act as "switch motifs" to control chromatin accessibility and enhancer activity. Mechanistically, the SWI/SNF complex is selectively required to mediate cooperative ZNF410 binding for CHD4 expression. Together, our findings expose a complex functional hierarchy of homotypic clustered motifs, which cooperate to fine-tune target gene expression.

High-intensity alcohol drinking during binge episodes contributes to the socioeconomic burden created by alcohol use disorders (AUDs), and nociceptin receptor (NOP) antagonists have emerged as a promising intervention. To better understand the contribution of the NOP system to binge drinking, we found that nociceptin-containing neurons of the lateral septum (LS) displayed increased excitability during withdrawal from binge-like alcohol drinking. LS activation promoted active avoidance and potentiated binge-like drinking behavior, whereas silencing of this population reduced alcohol drinking. LS form robust monosynaptic inputs locally within the LS and genetic deletion of NOP or microinjection of a NOP antagonist into the LS decreased alcohol intake. LS also project to the lateral hypothalamus and supramammillary nucleus of the hypothalamus, and genetic deletion of NOP from each site reduced alcohol drinking. Together, these findings implicate the septo-hypothalamic nociceptin system in excessive alcohol consumption and support NOP antagonist development for the treatment of AUD.

G protein-coupled receptor 3 (GPR3) is a class A orphan receptor characterized by high constitutive activity in the G signaling pathway. GPR3 has been implicated in Alzheimer's disease and the regulation of thermogenesis in human adipocytes, yet the molecular mechanisms underlying its self-activation and potential endogenous modulators remain unclear. In this study, we present cryo-electron microscopy (cryo-EM) structures of GPR3 in different oligomerization states, both in the absence and presence of G protein. Notably, in addition to the monomeric form of GPR3, our findings reveal a functional GPR3 dimer with an extensive dimer interface-a feature rarely observed in class A GPCRs. Moreover, oligomerization appears to be linked to a unique autoinhibition mechanism involving intracellular loops, which may regulate GPR3 signaling. Collectively, these results provide new insights into the oligomerization-modulated activation of orphan GPCRs, advancing our understanding of their signaling properties.