A genetic clog in the vitamin A transport machinery.

Chou et al. discover a new mode of maternal inheritance by analyzing human mutations in plasma retinol binding protein (RBP). Mechanistically, these mutations simultaneously lower RBP's affinity for vitamin A and greatly increase its affinity for its cell-surface receptor, thus dominantly blocking the transmembrane transport of vitamin A.

MicroRNA directly enhances mitochondrial translation during muscle differentiation.

MicroRNAs are well known to mediate translational repression and mRNA degradation in the cytoplasm. Various microRNAs have also been detected in membrane-compartmentalized organelles, but the functional significance has remained elusive. Here, we report that miR-1, a microRNA specifically induced during myogenesis, efficiently enters the mitochondria where it unexpectedly stimulates, rather than represses, the translation of specific mitochondrial genome-encoded transcripts. We show that this positive effect requires specific miR:mRNA base-pairing and Ago2, but not its functional partner GW182, which is excluded from the mitochondria. We provide evidence for the direct action of Ago2 in mitochondrial translation by crosslinking immunoprecipitation coupled with deep sequencing (CLIP-seq), functional rescue with mitochondria-targeted Ago2, and selective inhibition of the microRNA machinery in the cytoplasm. These findings unveil a positive function of microRNA in mitochondrial translation and suggest a highly coordinated myogenic program via miR-1-mediated translational stimulation in the mitochondria and repression in the cytoplasm.

Direct conversion of fibroblasts to neurons by reprogramming PTB-regulated microRNA circuits.

The induction of pluripotency or trans-differentiation of one cell type to another can be accomplished with cell-lineage-specific transcription factors. Here, we report that repression of a single RNA binding polypyrimidine-tract-binding (PTB) protein, which occurs during normal brain development via the action of miR-124, is sufficient to induce trans-differentiation of fibroblasts into functional neurons. Besides its traditional role in regulated splicing, we show that PTB has a previously undocumented function in the regulation of microRNA functions, suppressing or enhancing microRNA targeting by competitive binding on target mRNA or altering local RNA secondary structure. A key event during neuronal induction is the relief of PTB-mediated blockage of microRNA action on multiple components of the REST complex, thereby derepressing a large array of neuronal genes, including miR-124 and multiple neuronal-specific transcription factors, in nonneuronal cells. This converts a negative feedback loop to a positive one to elicit cellular reprogramming to the neuronal lineage.

Stabilization of ERK-Phosphorylated METTL3 by USP5 Increases m6A Methylation.

N6-methyladenosine (m6A) is the most abundant mRNA modification and is installed by the METTL3-METTL14-WTAP methyltransferase complex. Although the importance of m6A methylation in mRNA metabolism has been well documented recently, regulation of the m6A machinery remains obscure. Through a genome-wide CRISPR screen, we identify the ERK pathway and USP5 as positive regulators of the m6A deposition. We find that ERK phosphorylates METTL3 at S43/S50/S525 and WTAP at S306/S341, followed by deubiquitination by USP5, resulting in stabilization of the m6A methyltransferase complex. Lack of METTL3/WTAP phosphorylation reduces decay of m6A-labeled pluripotent factor transcripts and traps mouse embryonic stem cells in the pluripotent state. The same phosphorylation can also be found in ERK-activated human cancer cells and contribute to tumorigenesis. Our study reveals an unrecognized function of ERK in regulating m6A methylation.

N6-Deoxyadenosine Methylation in Mammalian Mitochondrial DNA.

N6-Methyldeoxyadenosine (6mA) has recently been shown to exist and play regulatory roles in eukaryotic genomic DNA (gDNA). However, the biological functions of 6mA in mammals have yet to be adequately explored, largely due to its low abundance in most mammalian genomes. Here, we report that mammalian mitochondrial DNA (mtDNA) is enriched for 6mA. The level of 6mA in HepG2 mtDNA is at least 1,300-fold higher than that in gDNA under normal growth conditions, corresponding to approximately four 6mA modifications on each mtDNA molecule. METTL4, a putative mammalian methyltransferase, can mediate mtDNA 6mA methylation, which contributes to attenuated mtDNA transcription and a reduced mtDNA copy number. Mechanistically, the presence of 6mA could repress DNA binding and bending by mitochondrial transcription factor (TFAM). Under hypoxia, the 6mA level in mtDNA could be further elevated, suggesting regulatory roles for 6mA in mitochondrial stress response. Our study reveals DNA 6mA as a regulatory mark in mammalian mtDNA.

Transcriptome-wide Mapping of Internal N7-Methylguanosine Methylome in Mammalian mRNA.

N7-methylguanosine (m7G) is a positively charged, essential modification at the 5' cap of eukaryotic mRNA, regulating mRNA export, translation, and splicing. m7G also occurs internally within tRNA and rRNA, but its existence and distribution within eukaryotic mRNA remain to be investigated. Here, we show the presence of internal m7G sites within mammalian mRNA. We then performed transcriptome-wide profiling of internal m7G methylome using m7G-MeRIP sequencing (MeRIP-seq). To map this modification at base resolution, we developed a chemical-assisted sequencing approach that selectively converts internal m7G sites into abasic sites, inducing misincorporation at these sites during reverse transcription. This base-resolution m7G-seq enabled transcriptome-wide mapping of m7G in human tRNA and mRNA, revealing distribution features of the internal m7G methylome in human cells. We also identified METTL1 as a methyltransferase that installs a subset of m7G within mRNA and showed that internal m7G methylation could affect mRNA translation.

Soil moisture decline in China's monsoon loess critical zone: More a result of land-use conversion than climate change.

Soil moisture (SM) is essential for sustaining services from Earth's critical zone, a thin-living skin spanning from the canopy to groundwater. In the Anthropocene epoch, intensive afforestation has remarkably contributed to global greening and certain service improvements, often at the cost of reduced SM. However, attributing the response of SM in deep soil to such human activities is a great challenge because of the scarcity of long-term observations. Here, we present a 37 y (1985 to 2021) analysis of SM dynamics at two scales across China's monsoon loess critical zone. Site-scale data indicate that land-use conversion from arable cropland to forest/grassland caused an 18% increase in SM deficit over 0 to 18 m depth (P < 0.01). Importantly, this SM deficit intensified over time, despite limited climate change influence. Across the Loess Plateau, SM storage in 0 to 10 m layer exhibited a significant decreasing trend from 1985 to 2021, with a turning point in 1999 when starting afforestation. Compared with SM storage before 1999, the relative contributions of climate change and afforestation to SM decline after 1999 were -8% and 108%, respectively. This emphasizes the pronounced impacts of intensifying land-use conversions as the principal catalyst of SM decline. Such a decline shifts 18% of total area into an at-risk status, mainly in the semiarid region, thereby threatening SM security. To mitigate this risk, future land management policies should acknowledge the crucial role of intensifying land-use conversions and their interplay with climate change. This is imperative to ensure SM security and sustain critical zone services.

Activation of STAT6 by STING is critical for antiviral innate immunity.

STAT6 plays a prominent role in adaptive immunity by transducing signals from extracellular cytokines. We now show that STAT6 is required for innate immune signaling in response to virus infection. Viruses or cytoplasmic nucleic acids trigger STING (also named MITA/ERIS) to recruit STAT6 to the endoplasmic reticulum, leading to STAT6 phosphorylation on Ser(407) by TBK1 and Tyr(641), independent of JAKs. Phosphorylated STAT6 then dimerizes and translocates to the nucleus to induce specific target genes responsible for immune cell homing. Virus-induced STAT6 activation is detected in all cell-types tested, in contrast to the cell-type specific role of STAT6 in cytokine signaling, and Stat6(-/-) mice are susceptible to virus infection. Thus, STAT6 mediates immune signaling in response to both cytokines at the plasma membrane, and virus infection at the endoplasmic reticulum.

Observation of gauge invariance in a 71-site Bose-Hubbard quantum simulator.

The modern description of elementary particles, as formulated in the standard model of particle physics, is built on gauge theories1. Gauge theories implement fundamental laws of physics by local symmetry constraints. For example, in quantum electrodynamics Gauss's law introduces an intrinsic local relation between charged matter and electromagnetic fields, which protects many salient physical properties, including massless photons and a long-ranged Coulomb law. Solving gauge theories using classical computers is an extremely arduous task2, which has stimulated an effort to simulate gauge-theory dynamics in microscopically engineered quantum devices3-6. Previous achievements implemented density-dependent Peierls phases without defining a local symmetry7,8, realized mappings onto effective models to integrate out either matter or electric fields9-12, or were limited to very small systems13-16. However, the essential gauge symmetry has not been observed experimentally. Here we report the quantum simulation of an extended U(1) lattice gauge theory, and experimentally quantify the gauge invariance in a many-body system comprising matter and gauge fields. These fields are realized in defect-free arrays of bosonic atoms in an optical superlattice of 71 sites. We demonstrate full tunability of the model parameters and benchmark the matter-gauge interactions by sweeping across a quantum phase transition. Using high-fidelity manipulation techniques, we measure the degree to which Gauss's law is violated by extracting probabilities of locally gauge-invariant states from correlated atom occupations. Our work provides a way to explore gauge symmetry in the interplay of fundamental particles using controllable large-scale quantum simulators.

ARF6 plays a general role in targeting palmitoylated proteins from the Golgi to the plasma membrane.

Protein palmitoylation is a post-translational lipid modification of proteins. Accumulating evidence reveals that palmitoylation functions as a sorting signal to direct proteins to destinations; however, the sorting mechanism remains largely unknown. Here, we show that ARF6 plays a general role in targeting palmitoylated proteins from the Golgi to the plasma membrane (PM). Through shRNA screening, we identified ARF6 as the key small GTPase in targeting CD36, a palmitoylated protein, from the Golgi to the PM. We found that the N-terminal myristoylation of ARF6 is required for its binding with palmitoylated CD36, and the GTP-bound form of ARF6 facilitates the delivery of CD36 to the PM. Analysis of stable isotope labeling by amino acids in cell culture revealed that ARF6 might facilitate the sorting of 359 of the 531 palmitoylated PM proteins, indicating a general role of ARF6. Our study has thus identified a sorting mechanism for targeting palmitoylated proteins from the Golgi to the PM.

PQSDC: a parallel lossless compressor for quality scores data via sequences partition and run-length prediction mapping.

MOTIVATION: The quality scores data (QSD) account for 70% in compressed FastQ files obtained from the short and long reads sequencing technologies. Designing effective compressors for QSD that counterbalance compression ratio, time cost, and memory consumption is essential in scenarios such as large-scale genomics data sharing and long-term data backup. This study presents a novel parallel lossless QSD-dedicated compression algorithm named PQSDC, which fulfills the above requirements well. PQSDC is based on two core components: a parallel sequences-partition model designed to reduce peak memory consumption and time cost during compression and decompression processes, as well as a parallel four-level run-length prediction mapping model to enhance compression ratio. Besides, the PQSDC algorithm is also designed to be highly concurrent using multicore CPU clusters. RESULTS: We evaluate PQSDC and four state-of-the-art compression algorithms on 27 real-world datasets, including 61.857 billion QSD characters and 632.908 million QSD sequences. (1) For short reads, compared to baselines, the maximum improvement of PQSDC reaches 7.06% in average compression ratio, and 8.01% in weighted average compression ratio. During compression and decompression, the maximum total time savings of PQSDC are 79.96% and 84.56%, respectively; the maximum average memory savings are 68.34% and 77.63%, respectively. (2) For long reads, the maximum improvement of PQSDC reaches 12.51% and 13.42% in average and weighted average compression ratio, respectively. The maximum total time savings during compression and decompression are 53.51% and 72.53%, respectively; the maximum average memory savings are 19.44% and 17.42%, respectively. (3) Furthermore, PQSDC ranks second in compression robustness among the tested algorithms, indicating that it is less affected by the probability distribution of the QSD collections. Overall, our work provides a promising solution for QSD parallel compression, which balances storage cost, time consumption, and memory occupation primely. AVAILABILITY AND IMPLEMENTATION: The proposed PQSDC compressor can be downloaded from https://github.com/fahaihi/PQSDC.

CRF regulates pain sensation by enhancement of corticoaccumbal excitatory synaptic transmission.

Both peripheral and central corticotropin-releasing factor (CRF) systems have been implicated in regulating pain sensation. However, compared with the peripheral, the mechanisms underlying central CRF system in pain modulation have not yet been elucidated, especially at the neural circuit level. The corticoaccumbal circuit, a structure rich in CRF receptors and CRF-positive neurons, plays an important role in behavioral responses to stressors including nociceptive stimuli. The present study was designed to investigate whether and how CRF signaling in this circuit regulated pain sensation under physiological and pathological pain conditions. Our studies employed the viral tracing and circuit-, and cell-specific electrophysiological methods to label the CRF-containing circuit from the medial prefrontal cortex to the nucleus accumbens shell (mPFCCRF-NAcS) and record its neuronal propriety. Combining optogenetic and chemogenetic manipulation, neuropharmacological methods, and behavioral tests, we were able to precisely manipulate this circuit and depict its role in regulation of pain sensation. The current study found that the CRF signaling in the NAc shell (NAcS), but not NAc core, was necessary and sufficient for the regulation of pain sensation under physiological and pathological pain conditions. This process was involved in the CRF-mediated enhancement of excitatory synaptic transmission in the NAcS. Furthermore, we demonstrated that the mPFCCRF neurons monosynaptically connected with the NAcS neurons. Chronic pain increased the protein level of CRF in NAcS, and then maintained the persistent NAcS neuronal hyperactivity through enhancement of this monosynaptic excitatory connection, and thus sustained chronic pain behavior. These findings reveal a novel cell- and circuit-based mechanistic link between chronic pain and the mPFCCRF → NAcS circuit and provide a potential new therapeutic target for chronic pain.

Extracellular vesicle proteome unveils cathepsin B connection to Alzheimer's disease pathogenesis.

Extracellular vesicles (EVs) are membrane vesicles that are released extracellularly and considered to be implicated in the pathogenesis of neurodegenerative diseases including Alzheimer's disease. Here, CSF EVs of 16 ATN-classified cases were subjected to quantitative proteome analysis. In these CSF EVs, levels of 11 proteins were significantly altered during the ATN stage transitions (P < 0.05 and fold-change > 2.0). These proteins were thought to be associated with Alzheimer's disease pathogenesis and represent candidate biomarkers for pathogenic stage classification. Enzyme-linked immunosorbent assay analysis of CSF and plasma EVs revealed altered levels of cathepsin B (CatB) during the ATN transition (seven ATN groups in validation set, n = 136). The CSF and plasma EV CatB levels showed a negative correlation with CSF amyloid-ß42 concentrations. This proteomic landscape of CSF EVs in ATN classifications can depict the molecular framework of Alzheimer's disease progression, and CatB may be considered a promising candidate biomarker and therapeutic target in Alzheimer's disease amyloid pathology.

Structural and functional abnormalities in first-episode drug-naïve pediatric idiopathic generalized epilepsy.

The aim of this study was to investigate brain structure and corresponding static and dynamic functional connectivity (sFC & dFC) abnormalities in untreated, first-episode pediatric idiopathic generalized epilepsy (IGE), with the goal of better understanding the underlying pathological mechanisms of IGE. Thirty-one children with IGE and 31 age-matched healthy controls (HC) were recruited. Structural magnetic resonance imaging (sMRI) data were acquired, and voxel-based morphometry (VBM) analysis were performed to reveal abnormal gray matter volume (GMV). Moreover, sFC and dFC analyses were conducted using the brain areas exhibiting abnormal GMV as seed regions to explore abnormal functional couplings. Compared to HC, the IGE group exhibited increased GMV in left middle cingulate cortex (MCC) and right parahippocampus (ParaHipp). In addition, the analyses of dFC and sFC with MCC and ParaHipp as seeds revealed more extensive functional connectivity (FC) changes in dFC. Notably, the structurally and functionally abnormal brain areas were primarily localized in the default mode network (DMN). However, our study did not find any significant associations between these altered neuroimaging measurements and clinical outcomes. This study uncovered microstructural changes as well as corresponding sFC and dFC changes in patients with new-onset, untreated pediatric IGE. The affected brain regions were primarily located within the DMN, highlighting the DMN's crucial role in the development of pediatric IGE.

Mapping individual structural covariance network in development brain with dynamic time warping.

A conspicuous property of brain development or maturity is coupled with coordinated or synchronized brain structural co-variation. However, there is still a lack of effective approach to map individual structural covariance network. Here, we developed a novel individual structural covariance network method using dynamic time warping algorithm and applied it to delineate developmental trajectories of topological organizations of structural covariance network from childhood to early adulthood with a large sample of 655 individuals from Human Connectome Project-Development dataset. We found that the individual structural covariance network exhibited small-worldness property and the network global topological characteristics including small-worldness, global efficiency, local efficiency, and modularity linearly increase with age while the shortest path length linearly decreases with age. The nodal topological properties including betweenness and degree increased with age in language and emotion regulation related brain areas, while it decreased with age mainly in visual cortex, sensorimotor area, and hippocampus. Moreover, the topological attributes of structural covariance network as features could predict the age of each individual. Taken together, our results demonstrate that dynamic time warping can effectively map individual structural covariance network to uncover the developmental trajectories of network topology, which may facilitate future investigations to establish the links of structural co-variations with respect to cognition and disease vulnerability.

Sex-related cortical asymmetry in antipsychotic-naïve first-episode schizophrenia.

Schizophrenia has been considered to exhibit sex-related clinical differences that might be associated with distinctly abnormal brain asymmetries between sexes. One hundred and thirty-two antipsychotic-naïve first-episode patients with schizophrenia and 150 healthy participants were recruited in this study to investigate whether cortical asymmetry would exhibit sex-related abnormalities in schizophrenia. After a 1-yr follow-up, patients were rescanned to obtain the effect of antipsychotic treatment on cortical asymmetry. Male patients were found to show increased lateralization index while female patients were found to exhibit decreased lateralization index in widespread regions when compared with healthy participants of the corresponding sex. Specifically, the cortical asymmetry of male and female patients showed contrary trends in the cingulate, orbitofrontal, parietal, temporal, occipital, and insular cortices. This result suggested male patients showed a leftward shift of asymmetry while female patients showed a rightward shift of asymmetry in these above regions that related to language, vision, emotion, and cognition. Notably, abnormal lateralization indices remained stable after antipsychotic treatment. The contrary trends in asymmetry between female and male patients with schizophrenia together with the persistent abnormalities after antipsychotic treatment suggested the altered brain asymmetries in schizophrenia might be sex-related disturbances, intrinsic, and resistant to the effect of antipsychotic therapy.

Argonaute CLIP Defines a Deregulated miR-122-Bound Transcriptome that Correlates with Patient Survival in Human Liver Cancer.

MicroRNA-122, an abundant and conserved liver-specific miRNA, regulates hepatic metabolism and functions as a tumor suppressor, yet systematic and direct biochemical elucidation of the miR-122 target network remains incomplete. To this end, we performed Argonaute crosslinking immunoprecipitation (Argonaute [Ago]-CLIP) sequencing in miR-122 knockout and control mouse livers, as well as in matched human hepatocellular carcinoma (HCC) and benign liver tissue to identify miRNA target sites transcriptome-wide in two species. We observed a majority of miR-122 binding on 3' UTRs and coding exons followed by extensive binding to other genic and non-genic sites. Motif analysis of miR-122-dependent binding revealed a G-bulged motif in addition to canonical motifs. A large number of miR-122 targets were found to be species specific. Upregulation of several common mouse and human targets, most notably BCL9, predicted survival in HCC patients. These results broadly define the molecular consequences of miR-122 downregulation in hepatocellular carcinoma.

The neutralizing breadth of antibodies targeting diverse conserved epitopes between SARS-CoV and SARS-CoV-2.

Antibody therapeutics for the treatment of COVID-19 have been highly successful. However, the recent emergence of the Omicron variant has posed a challenge, as it evades detection by most existing SARS-CoV-2 neutralizing antibodies (nAbs). Here, we successfully generated a panel of SARS-CoV-2/SARS-CoV cross-neutralizing antibodies by sequential immunization of the two pseudoviruses. Of the potential candidates, we found that nAbs X01, X10, and X17 offer broad neutralizing potential against most variants of concern, with X17 further identified as a Class 5 nAb with undiminished neutralization against the Omicron variant. Cryo-electron microscopy structures of the three antibodies together in complex with each of the spike proteins of the prototypical SARS-CoV, SARS-CoV-2, and Delta and Omicron variants of SARS-CoV-2 defined three nonoverlapping conserved epitopes on the receptor-binding domain. The triple-antibody mixture exhibited enhanced resistance to viral evasion and effective protection against infection of the Beta variant in hamsters. Our findings will aid the development of antibody therapeutics and broad vaccines against SARS-CoV-2 and its emerging variants.

Association of healthy lifestyle behaviours with incident irritable bowel syndrome: a large population-based prospective cohort study.

OBJECTIVES: To evaluate the association between healthy lifestyle behaviours and the incidence of irritable bowel syndrome (IBS). DESIGN: Population-based prospective cohort study. SETTING: The UK Biobank. PARTICIPANTS: 64 268 adults aged 37 to 73 years who had no IBS diagnosis at baseline were enrolled between 2006 and 2010 and followed up to 2022. MAIN EXPOSURE: The five healthy lifestyle behaviours studied were never smoking, optimal sleep, high level of vigorous physical activity, high dietary quality and moderate alcohol intake. MAIN OUTCOME MEASURE: The incidence of IBS. RESULTS: During a mean follow-up of 12.6 years, 961 (1.5%) incident IBS cases were recorded. Among the 64 268 participants (mean age 55.9 years, 35 342 (55.0%) female, 7604 (11.8%) reported none of the five healthy lifestyle behaviours, 20 662 (32.1%) reported 1 behaviour, 21 901 (34.1%) reported 2 behaviours and 14 101 (21.9%) reported 3 to 5 behaviours at baseline. The multivariable adjusted hazard ratios associated with having 1, 2 and 3 to 5 behaviours for IBS incidence were 0.79 (95% confidence intervals 0.65 to 0.96), 0.64 (0.53 to 0.78) and 0.58 (0.46 to 0.72), respectively (P for trend <0.001). Never smoking (0.86, 0.76 to 0.98, P=0.02), high level of vigorous physical activity (0.83, 0.73 to 0.95, P=0.006) and optimal sleep (0.73, 0.60 to 0.88, P=0.001) demonstrated significant independent inverse associations with IBS incidence. No significant interactions were observed between these associations and age, sex, employment status, geographic location, gastrointestinal infection, endometriosis, family history of IBS or lifestyle behaviours. CONCLUSIONS: Adhering to a higher number of healthy lifestyle behaviours is significantly associated with a lower incidence of IBS in the general population. Our findings suggest the potential of lifestyle modifications as a primary prevention strategy for IBS.

Disinhibition of Mesolimbic Dopamine Circuit by the Lateral Hypothalamus Regulates Pain Sensation.

Our recent study demonstrated the critical role of the mesolimbic dopamine (DA) circuit and its brain-derived neurotropic factor (BDNF) signaling in mediating neuropathic pain. The present study aims to investigate the functional role of GABAergic inputs from the lateral hypothalamus (LH) to the ventral tegmental area (VTA; LHGABA→VTA) in regulating the mesolimbic DA circuit and its BDNF signaling underlying physiological and pathologic pain. We demonstrated that optogenetic manipulation of the LHGABA→VTA projection bidirectionally regulated pain sensation in naive male mice. Optogenetic inhibition of this projection generated an analgesic effect in mice with pathologic pain induced by chronic constrictive injury (CCI) of the sciatic nerve and persistent inflammatory pain by complete Freund's adjuvant (CFA). Trans-synaptic viral tracing revealed a monosynaptic connection between LH GABAergic neurons and VTA GABAergic neurons. Functionally, in vivo calcium/neurotransmitter imaging showed an increased DA neuronal activity, decreased GABAergic neuronal activity in the VTA, and increased dopamine release in the NAc, in response to optogenetic activation of the LHGABA→VTA projection. Furthermore, repeated activation of the LHGABA→VTA projection was sufficient to increase the expression of mesolimbic BDNF protein, an effect seen in mice with neuropathic pain. Inhibition of this circuit induced a decrease in mesolimbic BDNF expression in CCI mice. Interestingly, the pain behaviors induced by activation of the LHGABA→VTA projection could be prevented by pretreatment with intra-NAc administration of ANA-12, a TrkB receptor antagonist. These results demonstrated that LHGABA→VTA projection regulated pain sensation by targeting local GABAergic interneurons to disinhibit the mesolimbic DA circuit and regulating accumbal BDNF release.SIGNIFICANCE STATEMENT The mesolimbic dopamine (DA) system and its brain-derived neurotropic factor (BDNF) signaling have been implicated in pain regulation, however, underlying mechanisms remain poorly understood. The lateral hypothalamus (LH) sends different afferent fibers into and strongly influences the function of mesolimbic DA system. Here, utilizing cell type- and projection-specific viral tracing, optogenetics, in vivo calcium and neurotransmitter imaging, our current study identified the LHGABA→VTA projection as a novel neural circuit for pain regulation, possibly by targeting the VTA GABA-ergic neurons to disinhibit mesolimbic pathway-specific DA release and BDNF signaling. This study provides a better understanding of the role of the LH and mesolimbic DA system in physiological and pathological pain.