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1.
Cell ; 186(7): 1352-1368.e18, 2023 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-37001500

RESUMEN

Resilience enables mental elasticity in individuals when rebounding from adversity. In this study, we identified a microcircuit and relevant molecular adaptations that play a role in natural resilience. We found that activation of parvalbumin (PV) interneurons in the primary auditory cortex (A1) by thalamic inputs from the ipsilateral medial geniculate body (MG) is essential for resilience in mice exposed to chronic social defeat stress. Early attacks during chronic social defeat stress induced short-term hyperpolarizations of MG neurons projecting to the A1 (MGA1 neurons) in resilient mice. In addition, this temporal neural plasticity of MGA1 neurons initiated synaptogenesis onto thalamic PV neurons via presynaptic BDNF-TrkB signaling in subsequent stress responses. Moreover, optogenetic mimicking of the short-term hyperpolarization of MGA1 neurons, rather than merely activating MGA1 neurons, elicited innate resilience mechanisms in response to stress and achieved sustained antidepressant-like effects in multiple animal models, representing a new strategy for targeted neuromodulation.


Asunto(s)
Corteza Auditiva , Ratones , Animales , Corteza Auditiva/metabolismo , Tálamo/fisiología , Neuronas/metabolismo , Cuerpos Geniculados , Interneuronas/fisiología , Parvalbúminas/metabolismo
2.
Cell ; 186(9): 1968-1984.e20, 2023 04 27.
Artículo en Inglés | MEDLINE | ID: mdl-37040760

RESUMEN

Somatic mutations in nonmalignant tissues accumulate with age and injury, but whether these mutations are adaptive on the cellular or organismal levels is unclear. To interrogate genes in human metabolic disease, we performed lineage tracing in mice harboring somatic mosaicism subjected to nonalcoholic steatohepatitis (NASH). Proof-of-concept studies with mosaic loss of Mboat7, a membrane lipid acyltransferase, showed that increased steatosis accelerated clonal disappearance. Next, we induced pooled mosaicism in 63 known NASH genes, allowing us to trace mutant clones side by side. This in vivo tracing platform, which we coined MOSAICS, selected for mutations that ameliorate lipotoxicity, including mutant genes identified in human NASH. To prioritize new genes, additional screening of 472 candidates identified 23 somatic perturbations that promoted clonal expansion. In validation studies, liver-wide deletion of Tbx3, Bcl6, or Smyd2 resulted in protection against hepatic steatosis. Selection for clonal fitness in mouse and human livers identifies pathways that regulate metabolic disease.


Asunto(s)
Enfermedades Metabólicas , Enfermedad del Hígado Graso no Alcohólico , Animales , Humanos , Masculino , Ratones , N-Metiltransferasa de Histona-Lisina/genética , Hígado/metabolismo , Mosaicismo , Enfermedad del Hígado Graso no Alcohólico/genética , Enfermedad del Hígado Graso no Alcohólico/metabolismo
3.
Cell ; 184(5): 1377-1391.e14, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33545088

RESUMEN

Rich fossil evidence suggests that many traits and functions related to terrestrial evolution were present long before the ancestor of lobe- and ray-finned fishes. Here, we present genome sequences of the bichir, paddlefish, bowfin, and alligator gar, covering all major early divergent lineages of ray-finned fishes. Our analyses show that these species exhibit many mosaic genomic features of lobe- and ray-finned fishes. In particular, many regulatory elements for limb development are present in these fishes, supporting the hypothesis that the relevant ancestral regulation networks emerged before the origin of tetrapods. Transcriptome analyses confirm the homology between the lung and swim bladder and reveal the presence of functional lung-related genes in early ray-finned fishes. Furthermore, we functionally validate the essential role of a jawed vertebrate highly conserved element for cardiovascular development. Our results imply the ancestors of jawed vertebrates already had the potential gene networks for cardio-respiratory systems supporting air breathing.


Asunto(s)
Evolución Biológica , Peces/genética , Aletas de Animales/fisiología , Animales , Fenómenos Fisiológicos Cardiovasculares , Sistema Cardiovascular/anatomía & histología , Extremidades/fisiología , Peces/clasificación , Genoma , Pulmón/anatomía & histología , Pulmón/fisiología , Filogenia , Receptores Odorantes/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcriptoma , Vertebrados/clasificación , Vertebrados/genética
4.
Cell ; 184(5): 1362-1376.e18, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33545087

RESUMEN

Lungfishes are the closest extant relatives of tetrapods and preserve ancestral traits linked with the water-to-land transition. However, their huge genome sizes have hindered understanding of this key transition in evolution. Here, we report a 40-Gb chromosome-level assembly of the African lungfish (Protopterus annectens) genome, which is the largest genome assembly ever reported and has a contig and chromosome N50 of 1.60 Mb and 2.81 Gb, respectively. The large size of the lungfish genome is due mainly to retrotransposons. Genes with ultra-long length show similar expression levels to other genes, indicating that lungfishes have evolved high transcription efficacy to keep gene expression balanced. Together with transcriptome and experimental data, we identified potential genes and regulatory elements related to such terrestrial adaptation traits as pulmonary surfactant, anxiolytic ability, pentadactyl limbs, and pharyngeal remodeling. Our results provide insights and key resources for understanding the evolutionary pathway leading from fishes to humans.


Asunto(s)
Adaptación Biológica , Evolución Biológica , Peces/genética , Secuenciación Completa del Genoma , Aletas de Animales/anatomía & histología , Aletas de Animales/fisiología , Animales , Extremidades/anatomía & histología , Extremidades/fisiología , Peces/anatomía & histología , Peces/clasificación , Peces/fisiología , Filogenia , Fenómenos Fisiológicos Respiratorios , Sistema Respiratorio/anatomía & histología , Vertebrados/genética
5.
Cell ; 177(3): 608-621.e12, 2019 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-30955891

RESUMEN

Normal tissues accumulate genetic changes with age, but it is unknown if somatic mutations promote clonal expansion of non-malignant cells in the setting of chronic degenerative diseases. Exome sequencing of diseased liver samples from 82 patients revealed a complex mutational landscape in cirrhosis. Additional ultra-deep sequencing identified recurrent mutations in PKD1, PPARGC1B, KMT2D, and ARID1A. The number and size of mutant clones increased as a function of fibrosis stage and tissue damage. To interrogate the functional impact of mutated genes, a pooled in vivo CRISPR screening approach was established. In agreement with sequencing results, examination of 147 genes again revealed that loss of Pkd1, Kmt2d, and Arid1a promoted clonal expansion. Conditional heterozygous deletion of these genes in mice was also hepatoprotective in injury assays. Pre-malignant somatic alterations are often viewed through the lens of cancer, but we show that mutations can promote regeneration, likely independent of carcinogenesis.


Asunto(s)
Hepatopatías/patología , Hígado/metabolismo , Regeneración , Animales , Enfermedad Crónica , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , Humanos , Hidrolasas/deficiencia , Hidrolasas/genética , Hígado/patología , Cirrosis Hepática/inducido químicamente , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Hepatopatías/genética , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Mutación , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Regeneración/fisiología , Canales Catiónicos TRPP/genética , Canales Catiónicos TRPP/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Secuenciación del Exoma
6.
Nature ; 613(7942): 145-152, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36517600

RESUMEN

Phytohormone signalling pathways have an important role in defence against pathogens mediated by cell-surface pattern recognition receptors and intracellular nucleotide-binding leucine-rich repeat class immune receptors1,2 (NLR). Pathogens have evolved counter-defence strategies to manipulate phytohormone signalling pathways to dampen immunity and promote virulence3. However, little is known about the surveillance of pathogen interference of phytohormone signalling by the plant innate immune system. The pepper (Capsicum chinense) NLR Tsw, which recognizes the effector nonstructural protein NSs encoded by tomato spotted wilt orthotospovirus (TSWV), contains an unusually large leucine-rich repeat (LRR) domain. Structural modelling predicts similarity between the LRR domain of Tsw and those of the jasmonic acid receptor COI1, the auxin receptor TIR1 and the strigolactone receptor partner MAX2. This suggested that NSs could directly target hormone receptor signalling to promote infection, and that Tsw has evolved a LRR resembling those of phytohormone receptors LRR to induce immunity. Here we show that NSs associates with COI1, TIR1 and MAX2 through a common repressor-TCP21-which interacts directly with these phytohormone receptors. NSs enhances the interaction of COI1, TIR1 or MAX2 with TCP21 and blocks the degradation of corresponding transcriptional repressors to disable phytohormone-mediated host immunity to the virus. Tsw also interacts directly with TCP21 and this interaction is enhanced by viral NSs. Downregulation of TCP21 compromised Tsw-mediated defence against TSWV. Together, our findings reveal that a pathogen effector targets TCP21 to inhibit phytohormone receptor function, promoting virulence, and a plant NLR protein has evolved to recognize this interference as a counter-virulence strategy, thereby activating immunity.


Asunto(s)
Capsicum , Enfermedades de las Plantas , Reguladores del Crecimiento de las Plantas , Inmunidad de la Planta , Proteínas de Plantas , Receptores de Reconocimiento de Patrones , Leucina , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/virología , Reguladores del Crecimiento de las Plantas/metabolismo , Inmunidad de la Planta/inmunología , Proteínas de Plantas/química , Proteínas de Plantas/inmunología , Proteínas de Plantas/metabolismo , Receptores de Reconocimiento de Patrones/química , Receptores de Reconocimiento de Patrones/inmunología , Receptores de Reconocimiento de Patrones/metabolismo , Reconocimiento de Inmunidad Innata , Capsicum/inmunología , Capsicum/metabolismo , Capsicum/virología , Virulencia
7.
Nature ; 609(7929): 959-963, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36171376

RESUMEN

Paired fins are a major innovation1,2 that evolved in the jawed vertebrate lineage after divergence from living jawless vertebrates3. Extinct jawless armoured stem gnathostomes show a diversity of paired body-wall extensions, ranging from skeletal processes to simple flaps4. By contrast, osteostracans (a sister group to jawed vertebrates) are interpreted to have the first true paired appendages in a pectoral position, with pelvic appendages evolving later in association with jaws5. Here we show, on the basis of articulated remains of Tujiaaspis vividus from the Silurian period of China, that galeaspids (a sister group to both osteostracans and jawed vertebrates) possessed three unpaired dorsal fins, an approximately symmetrical hypochordal tail and a pair of continuous, branchial-to-caudal ventrolateral fins. The ventrolateral fins are similar to paired fin flaps in other stem gnathostomes, and specifically to the ventrolateral ridges of cephalaspid osteostracans that also possess differentiated pectoral fins. The ventrolateral fins are compatible with aspects of the fin-fold hypothesis for the origin of vertebrate paired appendages6-10. Galeaspids have a precursor condition to osteostracans and jawed vertebrates in which paired fins arose initially as continuous pectoral-pelvic lateral fins that our computed fluid-dynamics experiments show passively generated lift. Only later in the stem lineage to osteostracans and jawed vertebrates did pectoral fins differentiate anteriorly. This later differentiation was followed by restriction of the remaining field of fin competence to a pelvic position, facilitating active propulsion and steering.


Asunto(s)
Aletas de Animales , Evolución Biológica , Fósiles , Vertebrados , Aletas de Animales/anatomía & histología , Animales , China , Maxilares/anatomía & histología , Filogenia , Vertebrados/anatomía & histología
8.
Nature ; 609(7929): 964-968, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36171375

RESUMEN

Mandibular teeth and dentitions are features of jawed vertebrates that were first acquired by the Palaeozoic ancestors1-3 of living chondrichthyans and osteichthyans. The fossil record currently points to the latter part of the Silurian period4-7 (around 425 million years ago) as a minimum date for the appearance of gnathostome teeth and to the evolution of growth and replacement mechanisms of mandibular dentitions in the subsequent Devonian period2,8-10. Here we provide, to our knowledge, the earliest direct evidence for jawed vertebrates by describing Qianodus duplicis, a new genus and species of an early Silurian gnathostome based on isolated tooth whorls from Guizhou province, China. The whorls possess non-shedding teeth arranged in a pair of rows that demonstrate a number of features found in modern gnathostome groups. These include lingual addition of teeth in offset rows and maintenance of this patterning throughout whorl development. Our data extend the record of toothed gnathostomes by 14 million years from the late Silurian into the early Silurian (around 439 million years ago) and are important for documenting the initial diversification of vertebrates. Our analyses add to mounting fossil evidence that supports an earlier emergence of jawed vertebrates as part of the Great Ordovician Biodiversification Event (approximately 485-445 million years ago).


Asunto(s)
Fósiles , Diente , Vertebrados , Animales , China , Peces/anatomía & histología , Historia Antigua , Filogenia , Diente/anatomía & histología , Vertebrados/anatomía & histología , Vertebrados/clasificación
9.
Nature ; 609(7929): 969-974, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36171377

RESUMEN

Modern representatives of chondrichthyans (cartilaginous fishes) and osteichthyans (bony fishes and tetrapods) have contrasting skeletal anatomies and developmental trajectories1-4 that underscore the distant evolutionary split5-7 of the two clades. Recent work on upper Silurian and Devonian jawed vertebrates7-10 has revealed similar skeletal conditions that blur the conventional distinctions between osteichthyans, chondrichthyans and their jawed gnathostome ancestors. Here we describe the remains (dermal plates, scales and fin spines) of a chondrichthyan, Fanjingshania renovata gen. et sp. nov., from the lower Silurian of China that pre-date the earliest articulated fossils of jawed vertebrates10-12. Fanjingshania possesses dermal shoulder girdle plates and a complement of fin spines that have a striking anatomical similarity to those recorded in a subset of stem chondrichthyans5,7,13 (climatiid 'acanthodians'14). Uniquely among chondrichthyans, however, it demonstrates osteichthyan-like resorptive shedding of scale odontodes (dermal teeth) and an absence of odontogenic tissues in its spines. Our results identify independent acquisition of these conditions in the chondrichthyan stem group, adding Fanjingshania to an increasing number of taxa7,15 nested within conventionally defined acanthodians16. The discovery of Fanjingshania provides the strongest support yet for a proposed7 early Silurian radiation of jawed vertebrates before their widespread appearance5 in the fossil record in the Lower Devonian series.


Asunto(s)
Peces , Fósiles , Filogenia , Animales , China , Peces/anatomía & histología , Peces/clasificación , Maxilares/anatomía & histología , Diente
10.
Nature ; 609(7929): 954-958, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36171378

RESUMEN

Molecular studies suggest that the origin of jawed vertebrates was no later than the Late Ordovician period (around 450 million years ago (Ma))1,2. Together with disarticulated micro-remains of putative chondrichthyans from the Ordovician and early Silurian period3-8, these analyses suggest an evolutionary proliferation of jawed vertebrates before, and immediately after, the end-Ordovician mass extinction. However, until now, the earliest complete fossils of jawed fishes for which a detailed reconstruction of their morphology was possible came from late Silurian assemblages (about 425 Ma)9-13. The dearth of articulated, whole-body fossils from before the late Silurian has long rendered the earliest history of jawed vertebrates obscure. Here we report a newly discovered Konservat-Lagerstätte, which is marked by the presence of diverse, well-preserved jawed fishes with complete bodies, from the early Silurian (Telychian age, around 436 Ma) of Chongqing, South China. The dominant species, a 'placoderm' or jawed stem gnathostome, which we name Xiushanosteus mirabilis gen. et sp. nov., combines characters from major placoderm subgroups14-17 and foreshadows the transformation of the skull roof pattern from the placoderm to the osteichthyan condition10. The chondrichthyan Shenacanthus vermiformis gen. et sp. nov. exhibits extensive thoracic armour plates that were previously unknown in this lineage, and include a large median dorsal plate as in placoderms14-16, combined with a conventional chondrichthyan bauplan18,19. Together, these species reveal a previously unseen diversification of jawed vertebrates in the early Silurian, and provide detailed insights into the whole-body morphology of the jawed vertebrates of this period.


Asunto(s)
Fósiles , Maxilares , Vertebrados , Animales , China , Peces/anatomía & histología , Peces/clasificación , Maxilares/anatomía & histología , Filogenia , Cráneo/anatomía & histología , Vertebrados/anatomía & histología , Vertebrados/clasificación
11.
Nucleic Acids Res ; 52(D1): D1519-D1529, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38000385

RESUMEN

The explosive amount of multi-omics data has brought a paradigm shift both in academic research and further application in life science. However, managing and reusing the growing resources of genomic and phenotype data points presents considerable challenges for the research community. There is an urgent need for an integrated database that combines genome-wide association studies (GWAS) with genomic selection (GS). Here, we present CropGS-Hub, a comprehensive database comprising genotype, phenotype, and GWAS signals, as well as a one-stop platform with built-in algorithms for genomic prediction and crossing design. This database encompasses a comprehensive collection of over 224 billion genotype data and 434 thousand phenotype data generated from >30 000 individuals in 14 representative populations belonging to 7 major crop species. Moreover, the platform implemented three complete functional genomic selection related modules including phenotype prediction, user model training and crossing design, as well as a fast SNP genotyper plugin-in called SNPGT specifically built for CropGS-Hub, aiming to assist crop scientists and breeders without necessitating coding skills. CropGS-Hub can be accessed at https://iagr.genomics.cn/CropGS/.


Asunto(s)
Productos Agrícolas , Bases de Datos Genéticas , Genómica , Genotipo , Fenotipo , Productos Agrícolas/genética , Genoma , Estudio de Asociación del Genoma Completo , Polimorfismo de Nucleótido Simple , Internet
12.
Proc Natl Acad Sci U S A ; 120(36): e2307356120, 2023 09 05.
Artículo en Inglés | MEDLINE | ID: mdl-37639585

RESUMEN

The nuclear envelope (NE) separates genomic DNA from the cytoplasm and regulates transport between the cytosol and the nucleus in eukaryotes. Nuclear stiffening enables the cell nucleus to protect itself from extensive deformation, loss of NE integrity, and genome instability. It is known that the reorganization of actin, lamin, and chromatin can contribute to nuclear stiffening. In this work, we show that structural alteration of NE also contributes to instantaneous nuclear stiffening under indentation. In situ mechanical characterization of cell nuclei in intact cells shows that nuclear stiffening and unfolding of NE wrinkles occur simultaneously at the indentation site. A positive correlation between the initial state of NE wrinkles, the unfolding of NE wrinkles, and the stiffening ratio (stiffness fold-change) is found. Additionally, NE wrinkles unfold throughout the nucleus outside the indentation site. Finite element simulation, which involves the purely passive process of structural unfolding, shows that unfolding of NE wrinkles alone can lead to an increase in nuclear stiffness and a reduction in stress and strain levels. Together, these results provide a perspective on how cell nucleus adapts to mechanical stimuli through structural alteration of the NE.


Asunto(s)
Núcleo Celular , Membrana Nuclear , Cromatina , Citosol , Citoplasma
13.
Proc Natl Acad Sci U S A ; 120(28): e2302226120, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37399403

RESUMEN

Plant intracellular nucleotide-binding domain, leucine-rich repeat-containing receptors (NLRs) activate a robust immune response upon detection of pathogen effectors. How NLRs induce downstream immune defense genes remains poorly understood. The Mediator complex plays a central role in transducing signals from gene-specific transcription factors to the transcription machinery for gene transcription/activation. In this study, we demonstrate that MED10b and MED7 of the Mediator complex mediate jasmonate-dependent transcription repression, and coiled-coil NLRs (CNLs) in Solanaceae modulate MED10b/MED7 to activate immunity. Using the tomato CNL Sw-5b, which confers resistance to tospovirus, as a model, we found that the CC domain of Sw-5b directly interacts with MED10b. Knockout/down of MED10b and other subunits including MED7 of the middle module of Mediator activates plant defense against tospovirus. MED10b was found to directly interact with MED7, and MED7 directly interacts with JAZ proteins, which function as transcriptional repressors of jasmonic acid (JA) signaling. MED10b-MED7-JAZ together can strongly repress the expression of JA-responsive genes. The activated Sw-5b CC interferes with the interaction between MED10b and MED7, leading to the activation of JA-dependent defense signaling against tospovirus. Furthermore, we found that CC domains of various other CNLs including helper NLR NRCs from Solanaceae modulate MED10b/MED7 to activate defense against different pathogens. Together, our findings reveal that MED10b/MED7 serve as a previously unknown repressor of jasmonate-dependent transcription repression and are modulated by diverse CNLs in Solanaceae to activate the JA-specific defense pathways.


Asunto(s)
Proteínas de Arabidopsis , Inmunidad de la Planta , Inmunidad de la Planta/genética , Ciclopentanos , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Complejo Mediador/genética , Complejo Mediador/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
14.
J Neurosci ; 44(7)2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38124211

RESUMEN

Autism spectrum disorder (ASD) is a neurodevelopmental condition characterized by persistent deficits in social communication and stereotyped behaviors. Although major advances in basic research on autism have been achieved in the past decade, and behavioral interventions can mitigate the difficulties that individuals with autism experience, little is known about the many fundamental issues of the interventions, and no specific medication has demonstrated efficiency for the core symptoms of ASD. Intermittent hypobaric hypoxia (IHH) is characterized by repeated exposure to lowered atmospheric pressure and oxygen levels, which triggers multiple physiological adaptations in the body. Here, using two mouse models of ASD, male Shank3B -/- and Fmr1 -/y mice, we found that IHH training at an altitude of 5,000 m for 4 h per day, for 14 consecutive days, ameliorated autistic-like behaviors. Moreover, IHH training enhanced hypoxia inducible factor (HIF) 1α in the dorsal raphe nucleus (DRN) and activated the DRN serotonergic neurons. Infusion of cobalt chloride into the DRN, to mimic IHH in increasing HIF1α expression or genetically knockdown PHD2 to upregulate HIF1α expression in the DRN serotonergic neurons, alleviated autistic-like behaviors in Shank3B -/- mice. In contrast, downregulation of HIF1α in DRN serotonergic neurons induced compulsive behaviors. Furthermore, upregulating HIF1α in DRN serotonergic neurons increased the firing rates of these neurons, whereas downregulation of HIF1α in DRN serotonergic neurons decreased their firing rates. These findings suggest that IHH activated DRN serotonergic neurons via upregulation of HIF1α, and thus ameliorated autistic-like phenotypes, providing a novel therapeutic option for ASD.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Ratones , Masculino , Animales , Trastorno Autístico/genética , Trastorno Autístico/terapia , Trastorno del Espectro Autista/genética , Trastorno del Espectro Autista/terapia , Núcleo Dorsal del Rafe , Neuronas Serotoninérgicas/fisiología , Hipoxia , Fenotipo , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil
15.
J Biol Chem ; 300(3): 105782, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38395304

RESUMEN

Intracellular vesicle fusion is driven by the soluble N-ethylmaleimide-sensitive factor attachment protein receptors (SNAREs) and their cofactors, including Sec1/Munc18 (SM), α-SNAP, and NSF. α-SNAP and NSF play multiple layers of regulatory roles in the SNARE assembly, disassembling the cis-SNARE complex and the prefusion SNARE complex. How SM proteins coupled with NSF and α-SNAP regulate SNARE-dependent membrane fusion remains incompletely understood. Munc18c, an SM protein involved in the exocytosis of the glucose transporter GLUT4, binds and activates target (t-) SNAREs to accelerate the fusion reaction through a SNARE-like peptide (SLP). Here, using an in vitro reconstituted system, we discovered that α-SNAP blocks the GLUT4 SNAREs-mediated membrane fusion. Munc18c interacts with t-SNAREs to displace α-SNAP, which overcomes the fusion inhibition. Furthermore, Munc18c shields the trans-SNARE complex from NSF/α-SNAP-mediated disassembly and accelerates SNARE-dependent fusion kinetics in the presence of NSF and α-SNAP. The SLP in domain 3a is indispensable in Munc18c-assisted resistance to NSF and α-SNAP. Together, our findings demonstrate that Munc18c protects the prefusion SNARE complex from α-SNAP and NSF, promoting SNARE-dependent membrane fusion through its SLP.


Asunto(s)
Fusión de Membrana , Proteínas Munc18 , Proteínas SNARE , Proteínas Solubles de Unión al Factor Sensible a la N-Etilmaleimida , Fusión de Membrana/fisiología , Proteínas Munc18/metabolismo , Proteínas Sensibles a N-Etilmaleimida/genética , Proteínas Sensibles a N-Etilmaleimida/metabolismo , Orgánulos/metabolismo , Péptidos/metabolismo , Proteínas SNARE/metabolismo , Proteínas Solubles de Unión al Factor Sensible a la N-Etilmaleimida/genética , Animales , Ratones
16.
Circulation ; 149(4): 317-329, 2024 01 23.
Artículo en Inglés | MEDLINE | ID: mdl-37965733

RESUMEN

BACKGROUND: Pathogenic variants in SCN5A can result in long QT syndrome type 3, a life-threatening genetic disease. Adenine base editors can convert targeted A T base pairs to G C base pairs, offering a promising tool to correct pathogenic variants. METHODS: We generated a long QT syndrome type 3 mouse model by introducing the T1307M pathogenic variant into the Scn5a gene. The adenine base editor was split into 2 smaller parts and delivered into the heart by adeno-associated virus serotype 9 (AAV9-ABEmax) to correct the T1307M pathogenic variant. RESULTS: Both homozygous and heterozygous T1307M mice showed significant QT prolongation. Carbachol administration induced Torsades de Pointes or ventricular tachycardia for homozygous T1307M mice (20%) but not for heterozygous or wild-type mice. A single intraperitoneal injection of AAV9-ABEmax at postnatal day 14 resulted in up to 99.20% Scn5a transcripts corrected in T1307M mice. Scn5a mRNA correction rate >60% eliminated QT prolongation; Scn5a mRNA correction rate <60% alleviated QT prolongation. Partial Scn5a correction resulted in cardiomyocytes heterogeneity, which did not induce severe arrhythmias. We did not detect off-target DNA or RNA editing events in ABEmax-treated mouse hearts. CONCLUSIONS: These findings show that in vivo AAV9-ABEmax editing can correct the variant Scn5a allele, effectively ameliorating arrhythmia phenotypes. Our results offer a proof of concept for the treatment of hereditary arrhythmias.


Asunto(s)
Trastorno del Sistema de Conducción Cardíaco , Edición Génica , Síndrome de QT Prolongado , Ratones , Animales , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/terapia , Síndrome de QT Prolongado/diagnóstico , Arritmias Cardíacas , Miocitos Cardíacos , Adenina , ARN Mensajero , Canal de Sodio Activado por Voltaje NAV1.5/genética , Mutación
17.
PLoS Pathog ; 19(12): e1011184, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38048361

RESUMEN

Polymerases encoded by segmented negative-strand RNA viruses cleave 5'-m7G-capped host transcripts to prime viral mRNA synthesis ("cap-snatching") to generate chimeric RNA, and trans-splicing occurs between viral and cellular transcripts. Bombyx mori cytoplasmic polyhedrosis virus (BmCPV), an RNA virus belonging to Reoviridae, is a major pathogen of silkworm (B. mori). The genome of BmCPV consists of 10 segmented double-stranded RNAs (S1-S10) from which viral RNAs encoding a protein are transcribed. In this study, chimeric silkworm-BmCPV RNAs, in which the sequence derived from the silkworm transcript could fuse with both the 5' end and the 3' end of viral RNA, were identified in the midgut of BmCPV-infected silkworms by RNA_seq and further confirmed by RT-PCR and Sanger sequencing. A novel chimeric RNA, HDAC11-S4 RNA 4, derived from silkworm histone deacetylase 11 (HDAC11) and the BmCPV S4 transcript encoding viral structural protein 4 (VP4), was selected for validation by in situ hybridization and Northern blotting. Interestingly, our results indicated that HDAC11-S4 RNA 4 was generated in a BmCPV RNA-dependent RNA polymerase (RdRp)-independent manner and could be translated into a truncated BmCPV VP4 with a silkworm HDAC11-derived N-terminal extension. Moreover, it was confirmed that HDAC11-S4 RNA 4 inhibited BmCPV proliferation, decreased the level of H3K9me3 and increased the level of H3K9ac. These results indicated that during infection with BmCPV, a novel mechanism, different from that described in previous reports, allows the genesis of chimeric silkworm-BmCPV RNAs with biological functions.


Asunto(s)
Bombyx , Reoviridae , Animales , Bombyx/genética , Interacciones Huésped-Patógeno , Reoviridae/genética , ARN Viral/genética , ARN Viral/metabolismo , Proliferación Celular
18.
Cell Mol Life Sci ; 81(1): 209, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710967

RESUMEN

As an integral lysosomal transmembrane protein, transmembrane protein 106B (TMEM106B) regulates several aspects of lysosomal function and is associated with neurodegenerative diseases. The TMEM106B gene mutations lead to lysosomal dysfunction and accelerate the pathological progression of Neurodegenerative diseases. Yet, the precise mechanism of TMEM106B in Neurodegenerative diseases remains unclear. Recently, different research teams discovered that TMEM106B is an amyloid protein and the C-terminal domain of TMEM106B forms amyloid fibrils in various Neurodegenerative diseases and normally elderly individuals. In this review, we discussed the physiological functions of TMEM106B. We also included TMEM106B gene mutations that cause neurodegenerative diseases. Finally, we summarized the identification and cryo-electronic microscopic structure of TMEM106B fibrils, and discussed the promising therapeutic strategies aimed at TMEM106B fibrils and the future directions for TMEM106B research in neurodegenerative diseases.


Asunto(s)
Proteínas de la Membrana , Mutación , Proteínas del Tejido Nervioso , Enfermedades Neurodegenerativas , Humanos , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Proteínas de la Membrana/química , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/patología , Proteínas del Tejido Nervioso/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/química , Animales , Lisosomas/metabolismo , Lisosomas/genética , Amiloide/metabolismo , Amiloide/genética , Amiloide/química
19.
Proc Natl Acad Sci U S A ; 119(26): e2121513119, 2022 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-35737832

RESUMEN

Both chronic obstructive pulmonary disease (COPD) and asthma are severe respiratory diseases. Bitter receptor-mediated bronchodilation is a potential therapy for asthma, but the mechanism underlying the agonistic relaxation of airway smooth muscle (ASM) is not well defined. By exploring the ASM relaxation mechanism of bitter substances, we observed that pretreatment with the bitter substances nearly abolished the methacholine (MCh)-induced increase in the ASM cell (ASMC) calcium concentration, thereby suppressing the calcium-induced contraction release. The ASM relaxation was significantly inhibited by simultaneous deletion of three Gαt proteins, suggesting an interaction between Tas2R and AChR signaling cascades in the relaxation process. Biochemically, the Gαt released by Tas2R activation complexes with AChR and blocks the Gαq cycling of AChR signal transduction. More importantly, a bitter substance, kudinoside A, not only attenuates airway constriction but also significantly inhibits pulmonary inflammation and tissue remodeling in COPD rats, indicating its modulation of additional Gαq-associated pathological processes. Thus, our results suggest that Tas2R activation may be an ideal strategy for halting multiple pathological processes of COPD.


Asunto(s)
Asma , Músculo Liso , Enfermedad Pulmonar Obstructiva Crónica , Receptores Acoplados a Proteínas G , Activación Transcripcional , Animales , Asma/genética , Asma/metabolismo , Asma/fisiopatología , Broncodilatadores/farmacología , Calcio/metabolismo , Músculo Liso/efectos de los fármacos , Músculo Liso/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/genética , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Ratas , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transducción de Señal
20.
Artículo en Inglés | MEDLINE | ID: mdl-38871183

RESUMEN

BACKGROUND: Inhalable biologics represent a promising approach to improve the efficacy and safety of asthma treatment. Although several monoclonal antibodies (mAbs) targeting IL-4Rα have been approved or are undergoing clinical trials, the development of inhalable mAbs targeting IL-4Rα presents significant challenges. OBJECTIVE: Capitalizing on the distinctive advantages of nanobodies (Nbs) in maintaining efficacy during storage and administration, we sought to develop a novel inhalable IL-4Rα Nb for effectively treating asthma. METHODS: Three IL-4Rα immunized Nb libraries were utilized to generate specific and functional IL-4Rα Nbs. LQ036, a bivalent Nb comprising two HuNb103 units, was constructed with a high affinity and specificity for hIL-4Rα. The efficacy, pharmacokinetic and safety of inhaled LQ036 were evaluated in B-hIL4/hIL4Ra humanized mice. RESULTS: LQ036 inhibited secreted embryonic alkaline phosphatase (SEAP) reporter activity, TF-1 cell proliferation, and suppressed pSTAT6 in T cells from asthma patients. Crystal structure analysis revealed a binding region similar to Dupilumab but with higher affinity, leading to better efficacy in blocking the signaling pathway. HuNb103 competed with IL-4 and IL-13 for IL-4Rα binding. Additionally, LQ036 significantly inhibited OVA-specific IgE levels in serum, CCL17 levels in BALF, bronchial mucous cell hyperplasia, and airway goblet cell hyperplasia in B-hIL4/hIL4Ra humanized mice. Inhaled LQ036 exhibited favorable pharmacokinetics, safety and tissue distribution, with higher concentrations observed in the lungs and bronchi. CONCLUSION: These findings from preclinical studies establish the safety and efficacy of inhaled LQ036, underscoring its potential as a pioneering inhalable biologic therapy for asthma.

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