RESUMO
Trace amine-associated receptor 1 (TAAR1) senses a spectrum of endogenous amine-containing metabolites (EAMs) to mediate diverse psychological functions and is useful for schizophrenia treatment without the side effects of catalepsy. Here, we systematically profiled the signaling properties of TAAR1 activation and present nine structures of TAAR1-Gs/Gq in complex with EAMs, clinical drugs, and synthetic compounds. These structures not only revealed the primary amine recognition pocket (PARP) harboring the conserved acidic D3.32 for conserved amine recognition and "twin" toggle switch for receptor activation but also elucidated that targeting specific residues in the second binding pocket (SBP) allowed modulation of signaling preference. In addition to traditional drug-induced Gs signaling, Gq activation by EAM or synthetic compounds is beneficial to schizophrenia treatment. Our results provided a structural and signaling framework for molecular recognition by TAAR1, which afforded structural templates and signal clues for TAAR1-targeted candidate compounds design.
Assuntos
Receptores Acoplados a Proteínas G , Transdução de Sinais , Humanos , Aminas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Esquizofrenia/metabolismoRESUMO
Physical or mental stress leads to neuroplasticity in the brain and increases the risk of depression and anxiety. Stress exposure causes the dysfunction of peripheral T lymphocytes. However, the pathological role and underlying regulatory mechanism of peripheral T lymphocytes in mood disorders have not been well established. Here, we show that the lack of CD4+ T cells protects mice from stress-induced anxiety-like behavior. Physical stress-induced leukotriene B4 triggers severe mitochondrial fission in CD4+ T cells, which further leads to a variety of behavioral abnormalities including anxiety, depression, and social disorders. Metabolomic profiles and single-cell transcriptome reveal that CD4+ T cell-derived xanthine acts on oligodendrocytes in the left amygdala via adenosine receptor A1. Mitochondrial fission promotes the de novo synthesis of purine via interferon regulatory factor 1 accumulation in CD4+ T cells. Our study implicates a critical link between a purine metabolic disorder in CD4+ T cells and stress-driven anxiety-like behavior.
Assuntos
Ansiedade/metabolismo , Comportamento Animal/fisiologia , Encefalopatias Metabólicas/metabolismo , Estresse Psicológico/metabolismo , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/patologia , Animais , Ansiedade/genética , Ansiedade/imunologia , Ansiedade/fisiopatologia , Encefalopatias Metabólicas/genética , Encefalopatias Metabólicas/fisiopatologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Modelos Animais de Doenças , Humanos , Camundongos , Dinâmica Mitocondrial/genética , Oligodendroglia/metabolismo , Oligodendroglia/patologia , Análise de Célula Única , Estresse Psicológico/genética , Estresse Psicológico/fisiopatologia , Transcriptoma/genética , Xantina/metabolismoRESUMO
Maintenance of energy level to drive movements and material exchange with the environment is a basic principle of life. AMP-activated protein kinase (AMPK) senses energy level and is a major regulator of cellular energy responses. The gamma subunit of AMPK senses elevated ratio of AMP to ATP and allosterically activates the alpha catalytic subunit to phosphorylate downstream effectors. Here, we report that knockout of AMPKγ, but not AMPKα, suppressed phosphorylation of eukaryotic translation elongation factor 2 (eEF2) induced by energy starvation. We identified PPP6C as an AMPKγ-regulated phosphatase of eEF2. AMP-bound AMPKγ sequesters PPP6C, thereby blocking dephosphorylation of eEF2 and thus inhibiting translation elongation to preserve energy and to promote cell survival. Further phosphoproteomic analysis identified additional targets of PPP6C regulated by energy stress in an AMPKγ-dependent manner. Thus, AMPKγ senses cellular energy availability to regulate not only AMPKα kinase, but also PPP6C phosphatase and possibly other effectors.
Assuntos
Proteínas Quinases Ativadas por AMP , Biossíntese de Proteínas , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Fosforilação , Fator 2 de Elongação de Peptídeos/metabolismoRESUMO
Nutrient sensing and damage sensing are two fundamental processes in living organisms. While hyperglycemia is frequently linked to diabetes-related vulnerability to microbial infection, how body glucose levels affect innate immune responses to microbial invasion is not fully understood. Here, we surprisingly found that viral infection led to a rapid and dramatic decrease in blood glucose levels in rodents, leading to robust AMPK activation. AMPK, once activated, directly phosphorylates TBK1 at S511, which triggers IRF3 recruitment and the assembly of MAVS or STING signalosomes. Consistently, ablation or inhibition of AMPK, knockin of TBK1-S511A, or increased glucose levels compromised nucleic acid sensing, while boosting AMPK-TBK1 cascade by AICAR or TBK1-S511E knockin improves antiviral immunity substantially in various animal models. Thus, we identify TBK1 as an AMPK substrate, reveal the molecular mechanism coupling a dual sensing of glucose and nuclei acids, and report its physiological necessity in antiviral defense.
Assuntos
Proteínas Quinases Ativadas por AMP , Ácidos Nucleicos , Animais , Proteínas Quinases Ativadas por AMP/genética , Imunidade Inata , Antivirais , GlucoseRESUMO
Replication fork reversal is a global response to replication stress in mammalian cells, but precisely how it occurs remains poorly understood. Here, we show that, upon replication stress, DNA topoisomerase IIalpha (TOP2A) is recruited to stalled forks in a manner dependent on the SNF2-family DNA translocases HLTF, ZRANB3, and SMARCAL1. This is accompanied by an increase in TOP2A SUMOylation mediated by the SUMO E3 ligase ZATT and followed by recruitment of a SUMO-targeted DNA translocase, PICH. Disruption of the ZATT-TOP2A-PICH axis results in accumulation of partially reversed forks and enhanced genome instability. These results suggest that fork reversal occurs via a sequential two-step process. First, HLTF, ZRANB3, and SMARCAL1 initiate limited fork reversal, creating superhelical strain in the newly replicated sister chromatids. Second, TOP2A drives extensive fork reversal by resolving the resulting topological barriers and via its role in recruiting PICH to stalled forks.
Assuntos
DNA Helicases/metabolismo , Replicação do DNA , DNA Topoisomerases Tipo II/metabolismo , Genoma Humano , Instabilidade Genômica , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , DNA Helicases/genética , DNA Topoisomerases Tipo II/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Células HeLa , Humanos , Proteínas de Ligação a Poli-ADP-Ribose/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Missense mutations of the tumor suppressor Neurofibromin 2 (NF2/Merlin/schwannomin) result in sporadic to frequent occurrences of tumorigenesis in multiple organs. However, the underlying pathogenicity of NF2-related tumorigenesis remains mostly unknown. Here we found that NF2 facilitated innate immunity by regulating YAP/TAZ-mediated TBK1 inhibition. Unexpectedly, patient-derived individual mutations in the FERM domain of NF2 (NF2m) converted NF2 into a potent suppressor of cGAS-STING signaling. Mechanistically, NF2m gained extreme associations with IRF3 and TBK1 and, upon innate nucleic acid sensing, was directly induced by the activated IRF3 to form cellular condensates, which contained the PP2A complex, to eliminate TBK1 activation. Accordingly, NF2m robustly suppressed STING-initiated antitumor immunity in cancer cell-autonomous and -nonautonomous murine models, and NF2m-IRF3 condensates were evident in human vestibular schwannomas. Our study reports phase separation-mediated quiescence of cGAS-STING signaling by a mutant tumor suppressor and reveals gain-of-function pathogenesis for NF2-related tumors by regulating antitumor immunity.
Assuntos
Imunidade Inata , Proteínas de Membrana/metabolismo , Mutação de Sentido Incorreto , Neoplasias/metabolismo , Neurofibromina 2/metabolismo , Nucleotidiltransferases/metabolismo , Evasão Tumoral , Animais , Feminino , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Células HEK293 , Humanos , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/metabolismo , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/metabolismo , Melanoma Experimental/patologia , Proteínas de Membrana/genética , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/patologia , Neurofibromina 2/genética , Nucleotidiltransferases/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de SinaisRESUMO
Mitochondrial morphology shifts rapidly to manage cellular metabolism, organelle integrity, and cell fate. It remains unknown whether innate nucleic acid sensing, the central and general mechanisms of monitoring both microbial invasion and cellular damage, can reprogram and govern mitochondrial dynamics and function. Here, we unexpectedly observed that upon activation of RIG-I-like receptor (RLR)-MAVS signaling, TBK1 directly phosphorylated DRP1/DNM1L, which disabled DRP1, preventing its high-order oligomerization and mitochondrial fragmentation function. The TBK1-DRP1 axis was essential for assembly of large MAVS aggregates and healthy antiviral immunity and underlay nutrient-triggered mitochondrial dynamics and cell fate determination. Knockin (KI) strategies mimicking TBK1-DRP1 signaling produced dominant-negative phenotypes reminiscent of human DRP1 inborn mutations, while interrupting the TBK1-DRP1 connection compromised antiviral responses. Thus, our findings establish an unrecognized function of innate immunity governing both morphology and physiology of a major organelle, identify a lacking loop during innate RNA sensing, and report an elegant mechanism of shaping mitochondrial dynamics.
Assuntos
Dinaminas/metabolismo , Mitocôndrias/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , RNA/metabolismo , Peixe-Zebra/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteína DEAD-box 58/genética , Proteína DEAD-box 58/metabolismo , Dinaminas/genética , Células HCT116 , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Mutação , Proteínas Serina-Treonina Quinases/genética , RNA/genética , Transdução de Sinais/genética , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismoRESUMO
YAP/TAZ transcriptional co-activators play pivotal roles in tumorigenesis. In the Hippo pathway, diverse signals activate the MST-LATS kinase cascade that leads to YAP/TAZ phosphorylation, and subsequent ubiquitination and proteasomal degradation by SCFß-TrCP . When the MST-LATS kinase cascade is inactive, unphosphorylated or dephosphorylated YAP/TAZ translocate into the nucleus to mediate TEAD-dependent gene transcription. Hippo signaling-independent YAP/TAZ activation in human malignancies has also been observed, yet the mechanism remains largely elusive. Here, we report that the ubiquitin E3 ligase HERC3 can promote YAP/TAZ activation independently of its enzymatic activity. HERC3 directly binds to ß-TrCP, blocks its interaction with YAP/TAZ, and thus prevents YAP/TAZ ubiquitination and degradation. Expression levels of HERC3 correlate with YAP/TAZ protein levels and expression of YAP/TAZ target genes in breast tumor cells and tissues. Accordingly, knockdown of HERC3 expression ameliorates tumorigenesis of breast cancer cells. Our results establish HERC3 as a critical regulator of the YAP/TAZ stability and a potential therapeutic target for breast cancer.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Neoplasias da Mama , Humanos , Feminino , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Transativadores/genética , Transativadores/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Sinalização YAP , Proteínas Contendo Repetições de beta-Transducina/genética , Proteínas Contendo Repetições de beta-Transducina/metabolismo , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transformação Celular Neoplásica/genética , Carcinogênese/genética , Ubiquitinação , Neoplasias da Mama/genética , Ubiquitinas/metabolismo , Ligases/genética , Fosfoproteínas/genética , Fosfoproteínas/metabolismoRESUMO
The transcriptional regulators YAP and TAZ play important roles in development, physiology, and tumorigenesis and are negatively controlled by the Hippo pathway. It is yet unknown why the YAP/ TAZ proteins are frequently activated in human malignancies in which the Hippo pathway is still active. Here, by a gain-of-function cancer metastasis screen, we discovered OTUB2 as a cancer stemness and metastasis-promoting factor that deubiquitinates and activates YAP/TAZ. We found OTUB2 to be poly-SUMOylated on lysine 233, and this SUMOylation enables it to bind YAP/TAZ. We also identified a yet-unknown SUMO-interacting motif (SIM) in YAP and TAZ required for their association with SUMOylated OTUB2. Importantly, EGF and oncogenic KRAS induce OTUB2 poly-SUMOylation and thereby activate YAP/TAZ. Our results establish OTUB2 as an essential modulator of YAP/TAZ and also reveal a novel mechanism via which YAP/TAZ activity is induced by oncogenic KRAS.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Neoplasias da Mama/enzimologia , Movimento Celular , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células-Tronco Neoplásicas/enzimologia , Fosfoproteínas/metabolismo , Tioléster Hidrolases/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/agonistas , Receptores ErbB/metabolismo , Feminino , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Lisina , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Metástase Neoplásica , Células-Tronco Neoplásicas/patologia , Fenótipo , Fosfoproteínas/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Proteólise , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais , Sumoilação , Tioléster Hidrolases/genética , Fatores de Tempo , Transativadores , Fatores de Transcrição , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas de Sinalização YAPRESUMO
Congenital scoliosis (CS), affecting approximately 0.5 to 1 in 1,000 live births, is commonly caused by congenital vertebral malformations (CVMs) arising from aberrant somitogenesis or somite differentiation. While Wnt/ß-catenin signaling has been implicated in somite development, the function of Wnt/planar cell polarity (Wnt/PCP) signaling in this process remains unclear. Here, we investigated the role of Vangl1 and Vangl2 in vertebral development and found that their deletion causes vertebral anomalies resembling human CVMs. Analysis of exome sequencing data from multiethnic CS patients revealed a number of rare and deleterious variants in VANGL1 and VANGL2, many of which exhibited loss-of-function and dominant-negative effects. Zebrafish models confirmed the pathogenicity of these variants. Furthermore, we found that Vangl1 knock-in (p.R258H) mice exhibited vertebral malformations in a Vangl gene dose- and environment-dependent manner. Our findings highlight critical roles for PCP signaling in vertebral development and predisposition to CVMs in CS patients, providing insights into the molecular mechanisms underlying this disorder.
Assuntos
Proteínas de Transporte , Polaridade Celular , Proteínas de Membrana , Coluna Vertebral , Peixe-Zebra , Animais , Peixe-Zebra/genética , Peixe-Zebra/embriologia , Humanos , Camundongos , Polaridade Celular/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Coluna Vertebral/anormalidades , Coluna Vertebral/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo , Escoliose/genética , Escoliose/congênito , Escoliose/metabolismo , Via de Sinalização Wnt/genética , Predisposição Genética para Doença , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , FemininoRESUMO
The transforming growth factor ß (TGF-ß) superfamily controls a wide spectrum of biological processes in metazoans, including cell proliferation, apoptosis, differentiation, cell-fate determination, and embryonic development. Deregulation of TGF-ß-Smad signaling contributes to developmental anomalies and a variety of disorders and diseases such as tumorigenesis, fibrotic disorders, and immune diseases. In cancer, TGF-ß has dual effects through its antiproliferative and prometastatic actions. At the cellular level, TGF-ß functions mainly through the canonical Smad-dependent pathway in a cell type-specific and context-dependent manner. Accumulating evidence has demonstrated that ubiquitination plays a vital role in regulating TGF-ß-Smad signaling. We summarize current progress on ubiquitination (Ub) and the ubiquitin ligases that regulate TGF-ß-Smad signaling.
Assuntos
Fenômenos Biológicos , Fator de Crescimento Transformador beta , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Transdução de Sinais/fisiologiaRESUMO
Protein lipidation, which regulates numerous biological pathways and plays crucial roles in the pharmaceutical industry, is not encoded by the genetic code but synthesized post-translationally. In the present study, we report a computational approach for designing lipidation mimics that fully recapitulate the biochemical properties of natural lipidation in membrane association and albumin binding. Furthermore, we establish an engineered system for co-translational incorporation of these lipidation mimics into virtually any desired position of proteins in Escherichia coli and mammalian cells. We demonstrate the utility of these length-tunable lipidation mimics in diverse applications, including improving the half-life and activity of therapeutic proteins in living mice, anchoring functional proteins to membrane by substituting natural lipidation, functionally characterizing proteins carrying different lengths of lipidation and determining the plasma membrane-binding capacity of a given compound. Our strategy enables gain-of-function studies of lipidation in hundreds of proteins and facilitates the creation of superior therapeutic candidates.
Assuntos
Mamíferos , Proteínas , Camundongos , Animais , Proteínas/química , Membrana Celular/metabolismoRESUMO
The parasite Plasmodium vivax preferentially invades human reticulocytes. Its merozoite surface protein 1 paralog (PvMSP1P), particularly the 19-kDa C-terminal region (PvMSP1P-19), has been shown to bind to reticulocytes, and this binding can be inhibited by antisera obtained by PvMSP1P-19 immunization. The molecular mechanism of interactions between PvMSP1P-19 and reticulocytes during P. vivax invasion, however, remains unclear. In this study, we analyzed the ability of MSP1P-19 to bind to different concentrations of reticulocytes and confirmed its reticulocyte preference. LC-MS analysis was used to identify two potential reticulocyte receptors, band3 and CD71, that interact with MSP1P-19. Both PvMSP1P-19 and its sister taxon Plasmodium cynomolgi MSP1P-19 were found to bind to the extracellular loop (loop 5) of band3, where the interaction of MSP1P-19 with band3 was chymotrypsin sensitive. Antibodies against band3-P5, CD71, and MSP1P-19 reduced the binding activity of PvMSP1P-19 and Plasmodium cynomolgi MSP1P-19 to reticulocytes, while MSP1P-19 proteins inhibited Plasmodium falciparum invasion in vitro in a concentration-dependent manner. To sum up, identification and characterization of the reticulocyte receptor is important for understanding the binding of reticulocytes by MSP1P-19.
Assuntos
Antígenos CD , Plasmodium vivax , Proteínas de Protozoários , Receptores da Transferrina , Reticulócitos , Plasmodium vivax/metabolismo , Plasmodium vivax/genética , Reticulócitos/metabolismo , Reticulócitos/parasitologia , Humanos , Proteínas de Protozoários/metabolismo , Proteínas de Protozoários/genética , Antígenos CD/metabolismo , Antígenos CD/genética , Receptores da Transferrina/metabolismo , Receptores da Transferrina/genética , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Proteína 1 de Troca de Ânion do Eritrócito/genética , Ligação Proteica , Proteína 1 de Superfície de Merozoito/metabolismo , Proteína 1 de Superfície de Merozoito/genética , Malária Vivax/parasitologia , Malária Vivax/metabolismo , AnimaisRESUMO
Anthocyanin is an important pigment responsible for plant coloration and beneficial to human health. Kale (Brassica oleracea var. acephala), a primary cool-season flowers and vegetables, is an ideal material to study anthocyanin biosynthesis and regulation mechanisms due to its anthocyanin-rich leaves. However, the underlying molecular mechanism of anthocyanin accumulation in kale remains poorly understood. Previously, we demonstrated that BoDFR1 is a key gene controlling anthocyanin biosynthesis in kale. Here, we discovered a 369-bp InDel variation in the BoDFR1 promoter between the two kale inbred lines with different pink coloration, which resulted in reduced transcriptional activity of the BoDFR1 gene in the light-pink line. With the 369-bp insertion as a bait, an R2R3-MYB repressor BoMYB4b was identified using the yeast one-hybrid screening. Knockdown of the BoMYB4b gene led to increased BoDFR1 expression and anthocyanin accumulation. An E3 ubiquitin ligase, BoMIEL1, was found to mediate the degradation of BoMYB4b, thereby promoting anthocyanin biosynthesis. Furthermore, the expression level of BoMYB4b was significantly reduced by light signals, which was attributed to the direct repression of the light-signaling factor BoMYB1R1 on the BoMYB4b promoter. Our study revealed that a novel regulatory module comprising BoMYB1R1, BoMIEL1, BoMYB4b, and BoDFR1 finely regulates anthocyanin accumulation in kale. The findings aim to establish a scientific foundation for genetic improvement of leaf color traits in kale, meanwhile, providing a reference for plant coloration studies.
Assuntos
Antocianinas , Brassica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Antocianinas/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Brassica/genética , Brassica/metabolismo , Regiões Promotoras Genéticas/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Folhas de Planta/metabolismo , Folhas de Planta/genética , Plantas Geneticamente Modificadas , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genéticaRESUMO
BACKGROUND AND AIMS: Epigenetic reprogramming and escape from terminal differentiation are poorly understood enabling characteristics of liver cancer. Keratin 19 (KRT19), classically known to form the intermediate filament cytoskeleton, is a marker of stemness and worse prognosis in liver cancer. This study aimed to address the functional roles of KRT19 in liver tumorigenesis and to elucidate the underlying mechanisms. APPROACH AND RESULTS: Using multiplexed genome editing of hepatocytes in vivo, we demonstrated that KRT19 promoted liver tumorigenesis in mice. Cell fractionation revealed a previously unrecognized nuclear fraction of KRT19. Tandem affinity purification identified histone deacetylase 1 and REST corepressor 1, components of the corepressor of RE-1 silencing transcription factor (CoREST) complex as KRT19-interacting proteins. KRT19 knockout markedly enhanced histone acetylation levels. Mechanistically, KRT19 promotes CoREST complex formation by enhancing histone deacetylase 1 and REST corepressor 1 interaction, thus increasing the deacetylase activity. ChIP-seq revealed hepatocyte-specific genes, such as hepatocyte nuclear factor 4 alpha ( HNF4A ), as direct targets of KRT19-CoREST. In addition, we identified forkhead box P4 as a direct activator of aberrant KRT19 expression in liver cancer. Furthermore, treatment of primary liver tumors and patient-derived xenografts in mice suggest that KRT19 expression has the potential to predict response to histone deacetylase 1 inhibitors especially in combination with lenvatinib. CONCLUSIONS: Our data show that nuclear KRT19 acts as a transcriptional corepressor through promoting the deacetylase activity of the CoREST complex, resulting in dedifferentiation of liver cancer. These findings reveal a previously unrecognized function of KRT19 in directly shaping the epigenetic landscape in cancer.
RESUMO
Somatosensory neurons are highly heterogeneous with distinct types of neural cells responding to specific stimuli. However, the distribution and roles of cell-type-specific long intergenic noncoding RNAs (lincRNAs) in somatosensory neurons remain largely unexplored. Here, by utilizing droplet-based single-cell RNA-seq (scRNA-seq) and full-length Smart-seq2, we show that lincRNAs, but not coding mRNAs, are enriched in specific types of mouse somatosensory neurons. Profiling of lincRNAs from single neurons located in dorsal root ganglia (DRG) identifies 200 lincRNAs localized in specific types or subtypes of somatosensory neurons. Among them, the conserved cell-type-specific lincRNA CLAP associates with pruritus and is abundantly expressed in somatostatin (SST)-positive neurons. CLAP knockdown reduces histamine-induced Ca2+ influx in cultured SST-positive neurons and in vivo reduces histamine-induced scratching in mice. In vivo knockdown of CLAP also decreases the expression of neuron-type-specific and itch-related genes in somatosensory neurons, and this partially depends on the RNA binding protein MSI2. Our data reveal a cell-type-specific landscape of lincRNAs and a function for CLAP in somatosensory neurons in sensory transmission.
Assuntos
Prurido , RNA Longo não Codificante , Células Receptoras Sensoriais , Animais , Camundongos , Histamina , Prurido/genética , RNA Longo não Codificante/genética , SensaçãoRESUMO
Airborne bacteria are an influential component of the Earth's microbiomes, but their community structure and biogeographic distribution patterns have yet to be understood. We analyzed the bacterial communities of 370 air particulate samples collected from 63 sites around the world and constructed an airborne bacterial reference catalog with more than 27 million nonredundant 16S ribosomal RNA (rRNA) gene sequences. We present their biogeographic pattern and decipher the interlacing of the microbiome co-occurrence network with surface environments of the Earth. While the total abundance of global airborne bacteria in the troposphere (1.72 × 1024 cells) is 1 to 3 orders of magnitude lower than that of other habitats, the number of bacterial taxa (i.e., richness) in the atmosphere (4.71 × 108 to 3.08 × 109) is comparable to that in the hydrosphere, and its maximum occurs in midlatitude regions, as is also observed in other ecosystems. The airborne bacterial community harbors a unique set of dominant taxa (24 species); however, its structure appears to be more easily perturbed, due to the more prominent role of stochastic processes in shaping community assembly. This is corroborated by the major contribution of surface microbiomes to airborne bacteria (averaging 46.3%), while atmospheric conditions such as meteorological factors and air quality also play a role. Particularly in urban areas, human impacts weaken the relative importance of plant sources of airborne bacteria and elevate the occurrence of potential pathogens from anthropogenic sources. These findings serve as a key reference for predicting planetary microbiome responses and the health impacts of inhalable microbiomes with future changes in the environment.