The prelimbic cortex is involved in operant reward seeking. However, the precise nature of its activity patterns and whether/how they differ between different types of rewards are largely unknown. We use miniscope calcium imaging to observe prelimbic activity during both food and cocaine seeking in freely behaving mice. We find that neurobehavioral representations remain stable across days within individual mice. Unexpectedly, our data reveal significant individual differences: some mice display high similarity in their prelimbic cortex activity patterns for both food and cocaine seeking, while others show no such overlap. These findings suggest that individual differences in the neural mechanisms underlying food and cocaine seeking could be a critical factor to consider when developing future addiction treatment strategies.

Sorafenib, the targeted therapy for hepatocellular carcinoma (HCC), has been utilized in clinics for over a decade. However, its effectiveness is severely hindered by acquired drug resistance, the mechanisms of which remain largely elusive. In this study, we identify that carbonic anhydrase 2 (CA2) is a key regulator of sorafenib resistance. Mechanistically, sorafenib treatment decreases intracellular pH (pH) by suppressing monocarboxylate transporter 4 (MCT4) expression, while high levels of CA2 counteract MCT4-mediated pH dysregulation upon sorafenib treatment, maintaining pH homeostasis to facilitate cell survival and sorafenib resistance. Targeting CA2 re-sensitizes resistant HCC cells to sorafenib both in vitro and in vivo. Importantly, analysis of clinical samples shows a strong correlation between CA2 expression levels and the therapeutic efficacy of sorafenib in HCC patients. Our findings highlight the significance of CA2 in facilitating sorafenib resistance and propose targeting CA2 as a potential strategy for overcoming sorafenib resistance in HCC patients.

Latent learning is a process that enables the brain to transform experiences into "cognitive maps," a form of implicit memory, without requiring reinforced training. To investigate its neural mechanisms, we record from hippocampal neurons in mice during latent learning of spatial maps and observe that the high-dimensional neural state space gradually transforms into a low-dimensional manifold that closely resembles the physical environment. This transformation process is associated with the neural reactivation of navigational experiences during sleep. Additionally, we identify a subset of hippocampal neurons that, rather than forming place fields in a novel environment, maintain weak spatial tuning but gradually develop correlated activity with other neurons. The elevated correlation introduces redundancy into the ensemble code, transforming the neural state space into a low-dimensional manifold that effectively links discrete place fields of place cells into a map-like structure. These results suggest a potential mechanism for latent learning of spatial maps in the hippocampus.

Macroautophagy (autophagy) involves the formation of phagophores that mature into autophagosomes. The impact of inhibiting autophagosome closure remains unclear. Here, we report the generation and analysis of mice with impaired autophagosome closure by targeting the ubiquitin E2 variant-like (UEVL) β strands of the endosomal sorting complex required for transport (ESCRT) I subunit VPS37A. The VPS37A UEVL mutation (Δ43-139) impairs bulk autophagic flux without disrupting ESCRT-I complex assembly and endosomal function. Homozygous mutant mice exhibit signs of autophagy impairment, including p62/SQSTM1 and ubiquitinated protein accumulation, neuronal dysfunction, growth retardation, antioxidant gene upregulation, and tissue abnormalities. However, about half of the mutant neonates survive to adulthood without severe liver injury. LC3 proximity proteomics reveals that the VPS37A UEVL mutation leads to active TANK-binding kinase 1 (TBK1) accumulation on phagophores, resulting in increased p62 phosphorylation and inclusion formation. These findings reveal a previously unappreciated role of LC3-conjugated phagophores in facilitating protein aggregation and sequestration, potentially alleviating proteotoxicity.

We performed a large-scale genome-wide analysis aiming to investigate the prevalence and strain-level diversity of Bifidobacteriaceae species in the human microbiome. We considered 9,528 publicly available human metagenomes and integrated them with 1,192 isolate genomes from different sources. The prevalence and abundance of Bifidobacteriaceae species in humans was linked to multiple host characteristics: they were reduced in older people and enriched in populations characterized by Westernized lifestyles with geography-specific patterns. Phylogenetic analysis highlighted 110 Bifidobacteriaceae species-level genome bins (SGBs), with 32 found in humans and 8 in food and probiotic sources. Functional annotation revealed a great diversity in carbohydrate-active enzyme families across these SGBs. We found potential subspecies for most of the SGBs prevalent in humans and identified patterns driven by age and geography. We provided evidence that strains used in probiotics were rarely identified in humans, with the only exception represented by Bifidobacterium animalis. We finally evaluated that the abundance of Bifidobacteriaceae species exhibited moderate and variable capabilities to predict health status in case-control studies.

Some insects have evolved beneficial relationships with intestinal microbes for sex pheromone production to communicate with conspecifics effectively. However, it is not clear whether the sex pheromone synthesis activity of intestinal microbes can be controlled by the host, and the molecular mechanisms need to be further unraveled. In this study, we find that rectal gland Bacillus species of male Bactrocera dorsalis specifically produce sex pheromones in the evening, which is significantly associated with glucose levels. In vitro Bacillus culture assays show that glucose levels significantly influence the amount of sex pheromone produced. Comparative rectal gland transcriptome analysis reveals that the expressions of the alpha-galactosidase gene (GLA), a Bactrocera dorsalis transcription factor (BDTF), and a pigment-dispersing factor (PDF) are responsible for producing glucose. Our findings reveal that the PDF-BDTF-GLA module influences the intestinal-microbe-produced sex pheromone by regulating glucose levels and advance our understanding of interactions between insects and their intestinal microbes.

Cerebral angiogenesis is well appreciated in development and after injury, but the extent to which it occurs across cortical regions in normal adult mice and the underlying mechanisms are incompletely understood. Using in vivo imaging, we show that angiogenesis in anterior-medial cortical regions (retrosplenial and sensorimotor cortex) was exceptionally rare. By contrast, angiogenesis was significantly elevated in posterior-lateral regions such as visual cortex, primarily within 200 μm of the cortical surface. There was no effect of sex on angiogenesis rates, nor were there regional differences in vessel pruning (for either sex). To understand the mechanisms, we surveyed gene expression and found that Notch-related genes were enriched in ultra-stable retrosplenial cortex. Using endothelial-specific knockdown of Notch1, cerebral angiogenesis was significantly increased along with genes implicated in angiogenesis (Apln, Angpt2, Cdkn1a). Our study shows that angiogenesis is regionally dependent and that manipulations of Notch1 could unlock the angiogenic potential of the mature vasculature.

Acetyl coenzyme A (acetyl-CoA), a versatile central metabolite, plays a critical role in various metabolic processes and protein acetylation. While its impact on tumor cell properties is well established, the connection between acetyl-CoA metabolism and immune evasion in tumors remains unclear. Here, we uncover a mechanism by which nucleo-cytosolic acetyl-CoA contributes to immune evasion through regulation of programmed death ligand 1 (PD-L1). Specifically, bioinformatics analysis reveals a negative correlation between acetyl-CoA metabolism and anti-tumor immunity across multiple cancers. Inhibition of the acetyl-CoA-producing enzyme ATP-citrate lyase (ACLY) leads to a re-invigoration of cytotoxic T cells and enhances the efficacy of immunotherapy. Mechanistically, nucleo-cytosolic acetyl-CoA promotes PD-L1 transcription via P300-dependent histone H3K27 acetylation at the promoter region of CD274. The ACLY-H3K27ac-PD-L1 axis is verified in clinical specimens and predicts poor immunotherapy response. Our findings suggest that targeting acetyl-CoA metabolism may act as a promising strategy to overcome immune evasion and improve the outcomes of cancer immunotherapy.

Ilaria Elia, guest editor of the cancer metabolism special issue, spoke with Cell Reports about her scientific interests and her lab's focus on investigating the metabolic interactions between cancer cells and immune cells within the tumor microenvironment. Ilaria also discussed recent developments and future directions in the field.

Ping Gao, guest editor of the cancer metabolism special issue, spoke with Cell Reports about his scientific interests and his lab's focus on investigating the metabolic reprogramming in cancer cells and immune cells in the tumor microenvironment. Ping also discussed recent developments and future directions in the field.

The genus Ruminococcus is dominant in the human gut, but higher levels of some species, such as R. gnavus, R. torques, and R. bromii, have been linked to health or disease. In this study, we analyzed >9,000 Ruminococcus metagenome-assembled genomes (MAGs) reconstructed from >5,000 subjects and revealed significant links between the prevalence of some species/subspecies and geographic origin, age, lifestyle, and disease, with subspecies prevalent in specific subpopulations showing divergent metabolic potential. Furthermore, Ruminococcus species from Lachnospiraceae encoded for carbohydrate-active enzymes (CAZy) potentially involved in the metabolism of human N- and O-glycans, whereas those from Oscillospiraceae appear to be more adapted toward fiber metabolism. These new findings contribute to elucidating the potential functional role of Ruminococcus in specific lifestyles and diseases and to decipher the diversity and the adaptation of members of this genus to the human gut.

PD-1 blockade enhances anti-tumoral CD8 T cell responses via type 1 conventional dendritic cells (cDC1s), but how cDC1s change the properties of intratumoral CD8 T cells remains to be determined. Here, we identified two populations of intratumoral CD8 T cells distinguished by their expression of asialo-ganglio-N-tetraosylceramide (asGM1). asGM1 and asGM1CD8 T cells show enriched expression of genes characteristic for precursor exhausted T (Tpex) cells and terminally exhausted T (Tex) cells, respectively. The in situ expression of Flt3L or inhibition of PD-1 each promote the differentiation of asGM1CD8 T cells into asGM1CD8 T cells via interleukin-12 (IL-12) while also increasing the expression of Tpex and effector-like T cell-associated genes and their effector functions. Both interventions selectively expand CD8 T cells, but only Flt3L expression broadens their T cell receptor (TCR) repertoire. These data indicate the distinct role of Flt3L in diversifying the TCR repertoire, offering potential solutions for immune checkpoint blockade-resistant cancers.

Microglia, brain innate immune cells, participate in the spread of inflammatory signals and aggregated proteins through secretion of extracellular vesicles (EVs). Selenoprotein P (Sepp1) is a potential regulator of microglial EV secretion. Here, we investigate the effect of Sepp1 silencing on microglial transcriptomics to elucidate the Sepp1 regulatory mechanism of EV secretion and validate this effect in APP knockin mice. Silencing of Sepp1 significantly reduces EV secretion and CD63 loading to EVs from BV-2 microglia, as determined by single-vesicle flow cytometry and super-resolution microscopy. Sepp1 deficiency downregulates EV biogenesis machinery, accompanied by increased lysosomal activity and lipid metabolism. Silencing of Sepp1 in astrocytes but not neurons suppresses EV secretion in vitro. Finally, Sepp1 silencing reduces EV secretion from activated neurodegenerative microglia associated with amyloid plaques in APP mouse brains in vivo. Sepp1 is thus an emerging therapeutic target for ameliorating microglia-mediated disease spread through EV secretion in neurodegenerative disorders.

Autism spectrum disorder (ASD) consists of diverse neurodevelopmental conditions where core behavioral symptoms are critical for diagnosis. Altered dopamine (DA) neurotransmission in the striatum has been suggested to contribute to the behavioral features of ASD. Here, we examine DA neurotransmission in a mouse model of ASD characterized by elevated expression of eukaryotic initiation factor 4E (eIF4E), a key regulator of cap-dependent translation, using a comprehensive approach that encompasses genetics, behavior, synaptic physiology, and imaging. The results indicate that increased eIF4E expression leads to behavioral inflexibility and impaired striatal DA release. The loss of normal DA neurotransmission is due to a defect in nicotinic receptor signaling that regulates calcium dynamics in dopaminergic axons. These findings provide a mechanistic understanding of ASD symptoms and offer a foundation for targeted therapeutic interventions by revealing the intricate interplay between eIF4E, DA neurotransmission, and behavioral flexibility.

The thymus derives from the endoderm of pharyngeal pouches (PPs). The number and location of PPs with thymus-forming potential differ among jawed vertebrates, and ectopic thymus locations in mice and humans suggest a broader thymus-forming potential in PP endoderm than previously ascribed. We used the quail-chick chimera system to test if non-canonical pouches could form a thymus and examined the role of pharyngeal arch (PA) mesenchyme in this process. After testing several tissue associations, we identified thymus-forming potential in both non-canonical second PP and canonical third/fourth PP endoderm. We found the 3/4PA and the ventral region of 2PA mesenchyme to be capable of positively regulating this potential, while the dorsal region of 2PA exerts an inhibitory effect. Transcriptomic analysis revealed a shared genetic program associated with thymic potential in PP endoderm and uncovered distinct signaling pathways mediating cellular interactions between PP endoderm and PA mesenchyme, which modulate this thymic potential.

The synthesis of magnetic nanoparticles (FeO or FeS) within the membrane-bound organelles known as magnetosomes in magnetotactic bacteria (MTB) is a remarkable example of microbial-controlled biomineralization. Studying MTB biomineralization is crucial not only for understanding the origin and evolution of magnetoreception and bacterial organelles but also for advancing biotechnological and biomedical applications of MTB cells and magnetosomes. After decades of research, MTB have revealed unexpected diversity and complexity. The mechanisms underlying magnetosome biomineralization in MTB have been continuously documented using a few model MTB strains. In this review, we provide an overview of recent findings related to MTB diversity and focus primarily on the current understanding of magnetosome biosynthesis. Additionally, we summarize the growing biotechnological and biomedical applications derived from molecular studies of MTB and their magnetosomes.

Alzheimer's disease (AD) is the most prevalent neurodegenerative disorder characterized by extracellular amyloid plaques and neuronal Tau tangles. A recent study found that the APOE3 Christchurch (APOECh) variant could delay AD progression. However, the underlying mechanisms remain unclear. In this study, we established neuron-microglia co-cultures and neuroimmune organoids using isogenic APOE3 and APOECh microglia derived from human induced pluripotent stem cells (hiPSCs) with PSEN1 mutant neurons or brain organoids. We show that APOECh microglia are resistant to Aβ-induced lipid peroxidation and ferroptosis and therefore preserve the phagocytic activity and promote pTau clearance, providing mechanistic insights into the neuroprotective role of APOE3Ch microglia. Moreover, we show that an APOE mimetic peptide can mimic the protective effects of APOECh microglia. These findings demonstrate that the APOECh microglia plays a causal role in microglial neuroprotection, which can be exploited for therapeutic development for AD.

Kaposi sarcoma-associated herpesvirus (KSHV) is an oncogenic γ-herpesvirus. Autophagy during KSHV entry has remained unexplored. We show that LC3 lipidation as a hallmark of autophagy is induced shortly after KSHV entry. LC3 co-localizes with KSHV in amphisomes during entry and loss of LC3 lipidation increases infection. Accordingly, NDP52, a receptor of selective autophagy, was recruited to endocytosed viral particles, and its reduction increased KSHV infection. Additionally, virus particles co-localized with the endolysosome damage sensor galectin-8 upon KSHV entry and depletion of galectin-8 promoted KSHV infection. Compared with herpes simplex virus, listeriolysin, adenovirus, and influenza virus, and in contrast to what was previously thought about enveloped viruses, KSHV binding to EphA2 by its envelope protein gH causes endolysosomal membrane damage, akin to non-enveloped viruses and bacteria. Taken together, our study identifies an important anti-viral role for galectin-8, NDP52, and the autophagy machinery at virus-damaged endosomes, restricting KSHV entry by selective autophagy.

Animals constantly face microbial challenges, and microbe-mediated infection protection is crucial for host survival. Identifying specific bacteria and their interactions with host intracellular surveillance systems is important but challenging. Here, we develop a "probiotics" screening system that identifies Escherichia coli mutants, such as ΔymcB, which protect hosts from Pseudomonas aeruginosa PA14 infection by activating the mitochondrial unfolded protein response (UPR). Genetic screening reveals that MDSS-1, a neuronal transmembrane protein, is crucial for sensing ΔymcB and triggering intestinal UPR. MDSS-1 functions as a potential receptor in ASE neurons, detecting ΔymcB and transmitting signals through neuropeptides, GPCRs, Wnt signaling, and endopeptidase inhibitors to activate intestinal UPRmt and enhance protection. Constitutive activation of MDSS-1 in ASE neurons is sufficient to induce UPR and confer infection resistance. This study uncovers a neuron-intestine communication mechanism, where ASE neurons detect bacteria and modulate the intestinal mitochondrial surveillance system for host adaptation to pathogens.

Free fatty acid receptors (FFARs) play critical roles in metabolic regulation and are potential therapeutic targets for metabolic and inflammatory diseases. A comprehensive understanding of the activation mechanisms and endogenous ligand selectivity of FFARs is essential for drug discovery. Here, we report two cryoelectron microscopy structures of the human FFAR1 bound to the endogenous ligand docosahexaenoic acid (DHA) and G protein as well as FFAR2 in complex with butyrate and G at 3.2 Å and 3.3 Å resolution, respectively. These structures highlight that distinct locations and sizes of the orthosteric ligand binding pockets are crucial determinants of the endogenous ligand selectivity of this receptor subfamily. Additionally, computational analysis reveals a potential allosteric ligand binding pocket in FFAR2. Furthermore, we observe that the upward movement of helix V upon endogenous ligand binding is responsible for receptor activation. These insights will significantly aid in the development of drugs targeting this receptor family.