RESUMO
Primate-specific genes (PSGs) tend to be expressed in the brain and testis. This phenomenon is consistent with brain evolution in primates but is seemingly contradictory to the similarity of spermatogenesis among mammals. Here, using whole-exome sequencing, we identified deleterious variants of X-linked SSX1 in six unrelated men with asthenoteratozoospermia. SSX1 is a PSG expressed predominantly in the testis, and the SSX family evolutionarily expanded independently in rodents and primates. As the mouse model could not be used for studying SSX1, we used a non-human primate model and tree shrews, which are phylogenetically similar to primates, to knock down (KD) Ssx1 expression in the testes. Consistent with the phenotype observed in humans, both Ssx1-KD models exhibited a reduced sperm motility and abnormal sperm morphology. Further, RNA sequencing indicated that Ssx1 deficiency influenced multiple biological processes during spermatogenesis. Collectively, our experimental observations in humans and cynomolgus monkey and tree shrew models highlight the crucial role of SSX1 in spermatogenesis. Notably, three of the five couples who underwent intra-cytoplasmic sperm injection treatment achieved a successful pregnancy. This study provides important guidance for genetic counseling and clinical diagnosis and, significantly, describes the approaches for elucidating the functions of testis-enriched PSGs in spermatogenesis.
Assuntos
Astenozoospermia , Tupaia , Animais , Masculino , Macaca fascicularis , Primatas , Sêmen , Motilidade dos Espermatozoides , TupaiidaeRESUMO
Although the continual expansion of the brain during primate evolution accounts for our enhanced cognitive capabilities, the drivers of brain evolution have scarcely been explored in these ancestral nodes. Here, we performed large-scale comparative genomic, transcriptomic, and epigenomic analyses to investigate the evolutionary alterations acquired by brain genes and provide comprehensive listings of innovatory genetic elements along the evolutionary path from ancestral primates to human. The regulatory sequences associated with brain-expressed genes experienced rapid change, particularly in the ancestor of the Simiiformes. Extensive comparisons of single-cell and bulk transcriptomic data between primate and nonprimate brains revealed that these regulatory sequences may drive the high expression of certain genes in primate brains. Employing in utero electroporation into mouse embryonic cortex, we show that the primate-specific brain-biased gene BMP7 was recruited, probably in the ancestor of the Simiiformes, to regulate neuronal proliferation in the primate ventricular zone. Our study provides a comprehensive listing of genes and regulatory changes along the brain evolution lineage of ancestral primates leading to human. These data should be invaluable for future functional studies that will deepen our understanding not only of the genetic basis of human brain evolution but also of inherited disease.
Assuntos
Encéfalo , Primatas , Camundongos , Humanos , Animais , Primatas/genética , Encéfalo/metabolismo , Evolução MolecularRESUMO
The focal adhesion protein Kindlin2 is essential for integrin activation, a process that is fundamental to cell-extracellular matrix adhesion. Kindlin 2 (Fermt2) is widely expressed in mouse embryos, and its absence causes lethality at the peri-implantation stage due to the failure to trigger integrin activation. The function of kindlin2 during embryogenesis has not yet been fully elucidated as a result of this early embryonic lethality. Here, we showed that kindlin2 is essential for neural crest (NC) formation in Xenopus embryos. Loss-of-function assays performed with kindlin2-specific morpholino antisense oligos (MOs) or with CRISPR/Cas9 techniques in Xenopus embryos severely inhibit the specification of the NC. Moreover, integrin-binding-deficient mutants of Kindlin2 rescued the phenotype caused by loss of kindlin2, suggesting that the function of kindlin2 during NC specification is independent of integrins. Mechanistically, we found that Kindlin2 regulates the fibroblast growth factor (FGF) pathway, and promotes the stability of FGF receptor 1. Our study reveals a novel function of Kindlin2 in regulating the FGF signaling pathway and provides mechanistic insights into the function of Kindlin2 during NC specification.
Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Proteínas de Membrana/metabolismo , Crista Neural/embriologia , Proteínas de Xenopus/metabolismo , Xenopus laevis/embriologia , Animais , Sistemas CRISPR-Cas/genética , Linhagem Celular , Embrião não Mamífero/metabolismo , Desenvolvimento Embrionário/genética , Desenvolvimento Embrionário/fisiologia , Regulação da Expressão Gênica no Desenvolvimento/genética , Técnicas de Inativação de Genes , Células HEK293 , Células HeLa , Humanos , Integrinas/metabolismo , Proteínas de Membrana/genética , Morfolinos/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/metabolismo , Transdução de Sinais/genética , Proteínas de Xenopus/genéticaRESUMO
The diversity of Central Asians has been shaped by multiple migrations and cultural diffusion. Although ancient DNA studies have revealed the demographic changes of the Central Asian since the Bronze Age, the contribution of the ancient populations to the modern Central Asian remains opaque. Herein, we performed high-coverage sequencing of 131 whole genomes of Indo-European-speaking Tajik and Turkic-speaking Kyrgyz populations to explore their genomic diversity and admixture history. By integrating the ancient DNA data, we revealed more details of the origins and admixture history of Central Asians. We found that the major ancestry of present-day Tajik populations can be traced back to the admixture of the Bronze Age Bactria-Margiana Archaeological Complex and Andronovo-related populations. Highland Tajik populations further received additional gene flow from the Tarim mummies, an isolated ancient North Eurasian-related population. The West Eurasian ancestry of Kyrgyz is mainly derived from Historical Era populations in Xinjiang of China. Furthermore, the recent admixture signals detected in both Tajik and Kyrgyz are ascribed to the expansions of Eastern Steppe nomadic pastoralists during the Historical Era.
Assuntos
DNA Antigo , Múmias , Povo Asiático/genética , Etnicidade , Fluxo Gênico , Genética Populacional , HumanosRESUMO
Munronin V (1), isolated from Munronia henryi Harms, is the first example, to the best of our knowledge, of an unprecedented 7/7/6 tricarbocyclic framework featuring an unusual A,B-seco-limonoid ring. The structures of munronin V were established from extensive spectroscopic and electronic circular dichroism (ECD) analyses. The novel A,B-seco with two seven-membered lactones was formed as a result of Baeyer-Villiger oxidation. Compound 1 activated autophagy and inhibited Tau pathology as revealed by flow cytometric analyses, confocal imaging analysis and western blotting, and this effect was mediated by transcription factor EB (TFEB). These findings suggested that 1 might have potential as a compound for combating Alzheimer's disease.
Assuntos
Limoninas , Proteínas tau , Humanos , Doença de Alzheimer , Autofagia , Limoninas/química , Limoninas/farmacologia , Extratos Vegetais/química , Meliaceae/químicaRESUMO
Stimulator of IFN genes (STING) is a key molecule that binds to cyclic dinucleotides produced by the cyclic GMP-AMP synthase to activate IFN expression and autophagy in the fight against microbial infection. The regulation of STING in the activation of IFN expression has been extensively reported, whereas the regulation of STING in the initiation of autophagy is still insufficiently determined. IFN-inducible guanylate-binding proteins (GBPs) are central to the cell-autonomous immunity in defending a host against viral, bacterial, and protozoan infections. In this study using the Chinese tree shrew (Tupaia belangeri chinensis), which is genetically close to primates, we found that Tupaia GBP1 (tGBP1) combines with Tupaia STING (tSTING), promotes autophagy, and moderately inhibits HSV type 1 (HSV-1) infection. The antiviral effects of tGBP1 are IFN independent. Mechanistically, tGBP1 interacted with tSTING, Tupaia sequestosome 1, and Tupaia microtubule associated protein 1 L chain 3, forming a complex which promotes autophagy in response to HSV-1 infection. This function of tGBP1 against HSV-1 infection was lost in tSTING knockout cells. Overexpression of either tSTING or its mutant tSTING-ΔCTT that can only activate autophagy rescued the anti-HSV-1 activity of tGBP1 in tSTING knockout cells. Our study not only elucidated the underlying mechanism of tGBP1 antiviral activity against HSV-1 infection, but also uncovered the regulation of tSTING in the initiation of autophagy in response to HSV-1 infection.
Assuntos
Autofagia/imunologia , Proteínas de Ligação ao GTP/imunologia , Herpes Simples/imunologia , Herpesvirus Humano 1/imunologia , Animais , Células HEK293 , Humanos , TupaiaRESUMO
Ganoapplins A and B (1 and 2) with a 6/6/6/5/6-fused pentacyclic skeleton containing an aromatic E ring, were obtained from Ganoderma applanatum. Their structures were established through extensive spectroscopic analyses, quantum chemical calculations, including calculated chemical shifts with DP4 + analysis and electronic circular dichroism (ECD). A plausible biosynthetic pathway for 1 and 2 was proposed. Furthermore, their roles in activating autophagy were investigated and the cellular assays showed that 1 and 2 can inhibit tau pathology by inducing autophagy, suggesting their potential against Alzheimer's disease (AD).
Assuntos
Ganoderma , Estrutura Molecular , Ganoderma/química , Dicroísmo Circular , Autofagia , EsqueletoRESUMO
Eleven monoterpenoid indole alkaloids, including three new ones, tabercrassines A-C (1-3), were isolated from the seeds of Tabernaemontana crassa. Tabercrassine A (1) is an ibogan-ibogan-type bisindole alkaloid which is formed by the polymerization of two classic ibogan-type monomers through a C3 unit aliphatic chain. Their structures were established by extensive analysis of HRESIMS, NMR, and ECD spectra. Cellular assays showed that alkaloids 1-3 all reduce Aß42 production and inhibit phospho-tau (Thr217), a new biomarker of Alzheimer's disease [AD] associated with BACE1-, NCSTN-, GSK3ß-, and CDK5-mediated pathways, suggesting these alkaloids' potential against AD.
Assuntos
Antineoplásicos Fitogênicos , Alcaloides de Triptamina e Secologanina , Tabernaemontana , Alcaloides de Triptamina e Secologanina/farmacologia , Alcaloides de Triptamina e Secologanina/química , Alcaloides Indólicos/farmacologia , Tabernaemontana/química , Secretases da Proteína Precursora do Amiloide , Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Ácido Aspártico Endopeptidases , Estrutura MolecularRESUMO
The rise and expansion of Tibetan Empire in the 7th to 9th centuries AD affected the course of history across East Eurasia, but the genetic impact of Tibetans on surrounding populations remains undefined. We sequenced 60 genomes for four populations from Pakistan and Tajikistan to explore their demographic history. We showed that the genomes of Balti people from Baltistan comprised 22.6-26% Tibetan ancestry. We inferred a single admixture event and dated it to about 39-21 generations ago, a period that postdated the conquest of Baltistan by the ancient Tibetan Empire. The analyses of mitochondrial DNA, Y, and X chromosome data indicated that both ancient Tibetan males and females were involved in the male-biased dispersal. Given the fact that the Balti people adopted Tibetan language and culture in history, our study suggested the impact of Tibetan Empire on Baltistan involved dominant cultural and minor demic diffusion.
Assuntos
Fluxo Gênico , Genoma Humano , Feminino , Humanos , Masculino , Paquistão , Tibet/etnologia , Sequenciamento Completo do GenomaRESUMO
BACKGROUND: Genome-wide association studies (GWASs) have identified multiple risk loci for Parkinson's disease (PD). However, identifying the functional (or potential causal) variants in the reported risk loci and elucidating their roles in PD pathogenesis remain major challenges. To identify the potential causal (or functional) variants in the reported PD risk loci and to elucidate their regulatory mechanisms, we report a functional genomics study of PD. METHODS: We first integrated chromatin immunoprecipitation sequencing (ChIP-Seq) (from neuronal cells and human brain tissues) data and GWAS-identified single-nucleotide polymorphisms (SNPs) in PD risk loci. We then conducted a series of experiments and analyses to validate the regulatory effects of these (i.e., functional) SNPs, including reporter gene assays, allele-specific expression (ASE), transcription factor (TF) knockdown, CRISPR-Cas9-mediated genome editing, and expression quantitative trait loci (eQTL) analysis. RESULTS: We identified 44 SNPs (from 11 risk loci) affecting the binding of 12 TFs and we validated the regulatory effects of 15 TF binding-disrupting SNPs. In addition, we also identified the potential target genes regulated by these TF binding-disrupting SNPs through eQTL analysis. Finally, we showed that 4 eQTL genes of these TF binding-disrupting SNPs were dysregulated in PD cases compared with controls. CONCLUSION: Our study systematically reveals the gene regulatory mechanisms of PD risk variants (including widespread disruption of CTCF binding), generates the landscape of potential PD causal variants, and pinpoints promising candidate genes for further functional characterization and drug development.
Assuntos
Estudo de Associação Genômica Ampla , Doença de Parkinson , Predisposição Genética para Doença/genética , Genômica , Humanos , Doença de Parkinson/genética , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
Melanoma differentiation-associated gene 5 (MDA5) is a key cytoplasmic dsRNA sensor. Upon binding to invading viral RNA, activated MDA5 is recruited to mitochondria and interacts with mitochondrial antiviral signaling gene (MAVS) to initiate innate antiviral immune responses. The elegant regulation of this process remains elusive. In this study, using the Chinese tree shrew (Tupaia belangeri chinensis), which is genetically close to primates, we identified the Tupaia oligoadenylate synthetases-like 1 (tOASL1) as a positive regulator of the Tupaia MDA5 (tMDA5) and Tupaia MAVS (tMAVS)-mediated IFN signaling. Overexpression of tOASL1 significantly potentiated the RNA virus-triggered induction of the type I IFNs and downstream antiviral genes. Conversely, knockdown of tOASL1 had an impaired antiviral immune response. Mechanistically, tOASL1 was associated with mitochondria and directly interacted with tMDA5 and tMAVS. Upon RNA virus infection, tOASL1 enhanced the interaction between tMDA5 and tMAVS via its OAS and UBL domains. Our results revealed a novel mechanism by which tOASL1 contributes to host antiviral responses via enhancing tMDA5 and tMAVS interaction.
Assuntos
2',5'-Oligoadenilato Sintetase/imunologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Imunidade Inata , Helicase IFIH1 Induzida por Interferon/imunologia , Infecções por Vírus de RNA/imunologia , Vírus de RNA/imunologia , RNA de Cadeia Dupla/imunologia , RNA Viral/imunologia , Animais , TupaiaRESUMO
The stimulator of IFN genes (STING; also known as MITA, TMEM173, MPYS, or ERIS) is generally regarded as a key adaptor protein for sensing pathogenic DNA genomes. However, its role in RNA viral signaling as part of the innate immunity system remains controversial. In this study, we identified two isoforms of STING (a full-length Tupaia STING [tSTING-FL] and a Tupaia STING short isoform [tSTING-mini]) in the Chinese tree shrew (Tupaia belangeri chinensis), a close relative of primates. tSTING-FL played a key role in the HSV-1-triggered type I IFN signaling pathway, whereas tSTING-mini was critical for RNA virus-induced antiviral signaling transduction. tSTING-mini, but not tSTING-FL, interacted with tMDA5-tLGP2 and tIRF3 in resting cells. Upon RNA virus infection, tSTING-mini caused a rapid enhancement of the tMDA5-tLGP2-mediated antiviral response and acted earlier than tSTING-FL. Furthermore, tSTING-mini was translocated from the cytoplasm to the nucleus during RNA virus infection and promoted tIRF3 phosphorylation through tSTING-mini-tIRF3 interaction, leading to a restriction of viral replication. After the initiation of antiviral effect, tSTING-mini underwent rapid degradation by tDTX3L-tPAPR9 via k48-linked ubiquitination through a proteasome-dependent pathway. Our results have shown alternative isoforms of STING counteract RNA virus infection in different ways.
Assuntos
Processamento Alternativo/genética , Fator Regulador 3 de Interferon/genética , Helicase IFIH1 Induzida por Interferon/genética , Proteínas de Membrana/genética , RNA Helicases/genética , Vírus de RNA/genética , Tupaia/genética , Animais , Linhagem Celular , Chlorocebus aethiops , Células HEK293 , Humanos , Imunidade Inata/genética , RNA Viral/genética , Transdução de Sinais/genética , Células Vero , Replicação Viral/genéticaRESUMO
Hepatitis C virus (HCV) infection is the cause of severe liver disease in many people. The restricted species tropism of HCV hinders the research and development of drugs and vaccines. The Chinese tree shrew (Tupaia belangeri chinensis) is a close relative of primates and can be infected by HCV, but the underlying mechanisms are unknown. In this study, we have characterized the functions of tree shrew MAVS (tMAVS) in response to HCV infection and defined the capacity of HCV replication. HCV was shown to be colocalized with tMAVS in primary tree shrew hepatocytes and cleaved tMAVS at site Cys508 via its NS3/4A protease, with a modulating effect by site Glu506 of tMAVS. The tMAVS cleavage by HCV NS3/4A impaired the IRF3-mediated induction of IFN-ß but maintained the activated NF-κB signaling in the tree shrew primary cells. Activation of the tMAVS-dependent NF-κB signaling inversely inhibited HCV replication and might limit the establishment of persistent infection. Overall, our study has revealed an elegant example of the balance between the host defenses and HCV infection via the MAVS-mediated antiviral signaling and has provided an insight into the mechanisms underpinning HCV infection in the Chinese tree shrew.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/imunologia , Hepacivirus/fisiologia , Hepatite C/imunologia , Evasão da Resposta Imune , Imunidade Inata , NF-kappa B/imunologia , Tupaia/imunologia , Replicação Viral/imunologia , Animais , Hepatite C/veterináriaRESUMO
Genome-wide association studies (GWASs) and genome-wide linkage studies (GWLSs) have identified numerous risk genes affecting the susceptibility to leprosy. However, most of the reported GWAS hits are noncoding variants and account for only part of the estimated heritability for this disease. In order to identify additional risk genes and map the potentially functional variants within the GWAS loci, we performed a three-stage study combining whole-exome sequencing (WES; discovery stage), targeted next-generation sequencing (NGS; screening stage), and refined validation of risk missense variants in 1,433 individuals with leprosy and 1,625 healthy control individuals from Yunnan Province, Southwest China. We identified and validated a rare damaging variant, rs142179458 (c.1045G>A [p.Asp349Asn]) in HIF1A, as contributing to leprosy risk (p = 4.95 × 10-9, odds ratio [OR] = 2.266). We were able to show that affected individuals harboring the risk allele presented with multibacillary leprosy at an earlier age (p = 0.025). We also confirmed the association between missense variant rs3764147 (c.760A>G [p.Ile254Val]) in the GWAS hit LACC1 (formerly C13orf31) and leprosy (p = 6.11 × 10-18, OR = 1.605). By using the population attributable fraction, we have shown that HIF1A and LACC1 are the major genes with missense variants contributing to leprosy risk in our study groups. Consistently, mRNA expression levels of both HIF1A and LACC1 were upregulated in the skin lesions of individuals with leprosy and in Mycobacterium leprae-stimulated cells, indicating an active role of HIF1A and LACC1 in leprosy pathogenesis.
Assuntos
Povo Asiático/genética , Etnicidade/genética , Predisposição Genética para Doença , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Hanseníase/genética , Mutação de Sentido Incorreto/genética , Proteínas/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Criança , Estudos de Coortes , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Fatores de Risco , Transativadores/genética , Regulação para Cima/genética , Sequenciamento do Exoma , Adulto JovemRESUMO
BACKGROUND: Over 200 schizophrenia risk loci have been identified by genome-wide association studies (GWASs). However, the majority of risk loci were identified in populations of European ancestry (EUR), potentially missing important biological insights. It is important to perform 5 GWASs in non-European populations. METHODS: To identify novel schizophrenia risk loci, we conducted a GWAS in Han Chinese population (3493 cases and 4709 controls). We then performed a large-scale meta-analysis (a total of 143,438 subjects) through combining our results with previous GWASs conducted in EAS and EUR. In addition, we also carried out comprehensive post-GWAS analysis, including heritability partitioning, enrichment of schizophrenia associations in tissues and cell types, trancscriptome-wide association study (TWAS), expression quantitative trait loci (eQTL) and differential expression analysis. RESULTS: We identified two new schizophrenia risk loci, including associations in SHISA9 (rs7192086, P = 4.92 × 10-08) and PES1 (rs57016637, P = 2.33 × 10-11) in Han Chinese population. A fixed-effect meta-analysis (a total of 143,438 subjects) with summary statistics from EAS and EUR identifies 15 novel genome-wide significant risk loci. Heritability partitioning with linkage disequilibrium score regression (LDSC) reveals a significant enrichment of schizophrenia heritability in conserved genomic regions, promoters, and enhancers. Tissue and cell-type enrichment analyses show that schizophrenia associations are significantly enriched in human brain tissues and several types of neurons, including cerebellum neurons, telencephalon inhibitory, and excitatory neurons. Polygenic risk score profiling reveals that GWAS summary statistics from trans-ancestry meta-analysis (EAS + EUR) improves prediction performance in predicting the case/control status of our sample. Finally, transcriptome-wide association study (TWAS) identifies risk genes whose cis-regulated expression change may have a role in schizophrenia. CONCLUSIONS: Our study identifies 17 novel schizophrenia risk loci and highlights the importance and necessity of conducting genetic study in different populations. These findings not only provide new insights into genetic etiology of schizophrenia, but also facilitate to delineate the pathophysiology of schizophrenia and develop new therapeutic targets.
Assuntos
Estudo de Associação Genômica Ampla , Esquizofrenia , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Proteínas de Ligação a RNA , Esquizofrenia/genética , TranscriptomaRESUMO
Previous genotyping-based assays have identified non-coding variants of several interleukins (ILs) being associated with genetic susceptibility to leprosy. However, understanding of the involvement of coding variants within all IL family genes in leprosy was still limited. To obtain the full mutation spectrum of all ILs in leprosy, we performed a targeted deep sequencing of coding regions of 58 ILs genes in 798 leprosy patients (age 56.2 ± 14.4; female 31.5%) and 990 healthy controls (age 38.1 ± 14.0; female 44.3%) from Yunnan, Southwest China. mRNA expression alterations of ILs in leprosy skin lesions or in response to M. leprae treatment were estimated by using publicly available expression datasets. Two coding variants in IL27 (rs17855750, p.S59A, p = 4.02 × 10-8 , odds ratio [OR] = 1.748) and IL1RN (rs45507693, p.A106T, p = 1.45 × 10-5 , OR = 3.629) were significantly associated with leprosy risk. mRNA levels of IL27 and IL1RN were upregulated in whole blood cells after M. leprae stimulation. These data showed that IL27 and IL1RN are leprosy risk genes. Further functional study is required for characterizing the exact role of ILs in leprosy.
Assuntos
Predisposição Genética para Doença/genética , Interleucinas/genética , Hanseníase/genética , Polimorfismo de Nucleotídeo Único/genética , Povo Asiático/genética , Estudos de Casos e Controles , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genéticaRESUMO
Chinese tree shrews (Tupaia belangeri chinensis) are increasingly used as an alternative experimental animal to non-human primates in studying viral infections. Guanylate-binding proteins (GBP) belong to interferon (IFN)-inducible GTPases and defend the mammalian cell interior against diverse invasive pathogens. Previously, we identified five tree shrew GBP genes (tGBP1, tGBP2, tGBP4, tGBP5, and tGBP7) and found that tGBP1 showed antiviral activity against vesicular stomatitis virus (VSV) and type 1 herpes simplex virus (HSV-1) infections. Here, we showed that the anti-VSV activity of tGBP1 was independent of its GTPase activity and isoprenylation. In response to VSV infection, instead of regulating IFN expression and autophagy, tGBP1 competed with the VSV nucleocapsid (N) protein in binding to the VSV phosphoprotein (VSV-P), leading to the repression of the primary transcription of the VSV genome. These observations constitute the first report of the potential mechanism underlying the inhibition of VSV by GBP1.
Assuntos
Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica , Genoma Viral , Fosfoproteínas/genética , Tupaia/genética , Vesiculovirus/metabolismo , Animais , Autofagia , Células HEK293 , Humanos , Interferons/metabolismo , Proteínas do Nucleocapsídeo/química , Ligação Proteica , Fatores de Transcrição/genética , Transcrição Gênica , Regulação para Cima , Proteínas Virais/química , Replicação Viral/efeitos dos fármacosRESUMO
The proto-oncogene ets1 is highly expressed in the pre-migratory and migratory neural crest (NC), and has been implicated in the delamination and migration of the NC cells. To identify the downstream target genes of Ets1 in this process, we did RNA sequencing (RNA-Seq) on wild-type and ets1 mutant X. tropicalis embryos. A list of genes with significantly differential expression was obtained by analyzing the RNA-Seq data. We validated the RNA-Seq data by quantitative PCR, and examined the expression pattern of the genes identified from this assay with whole mount in situ hybridization. A majority of the identified genes showed expression in migrating NC. Among them, the expression of microseminoprotein beta gene 3 (msmb3) was positively regulated by Ets1 in both X. laevis and X. tropicalis. Knockdown of msmb3 with antisense morpholino oligonucleotides or disruption of msmb3 by CRISPR/Cas9 both impaired the migratory streams of NC. Our study identified msmb3 as an Ets1 target gene and uncovered its function in maintaining neural crest migration pattern.
Assuntos
Embrião não Mamífero/citologia , Crista Neural/citologia , Proteínas Secretadas pela Próstata/fisiologia , Proteína Proto-Oncogênica c-ets-1/fisiologia , Xenopus/embriologia , Animais , Movimento Celular , Desenvolvimento Embrionário , Regulação da Expressão Gênica no Desenvolvimento , Proto-Oncogene Mas , RNA-SeqRESUMO
Two new quassinoids (1 and 2) were isolated from the twigs of Harrisonia perforata (Blanco) Merr. Perforalactone E (2) possesses an uncommon hexacyclic 1α,12α:5α,13α-dicyclo-9ßH-picrasane skeleton. Its structure was determined based on spectroscopic data and X-ray crystallography. Compounds 1 and 2 could significantly induce lysosomal biogenesis through transcriptional activation of lysosomal genes.
Assuntos
SimaroubaceaeRESUMO
During evolution, neural progenitor cells in the subventricular zone (SVZ) have fundamental functions, ranging from brain volume expansion to the generation of a six-layered neocortex. In lissencephalic animal models, such as rodents, the majority of neural progenitors in the SVZ are intermediate progenitor cells (IPCs). Most IPCs in rodents undergo neurogenic division, and only a small portion of them divide a very limited number of times to generate a few neurons. Meanwhile, in gyrencephalic animals, such as primates, IPCs are able to self-renew for up to five successive divisions. However, abundant IPCs with successive proliferative capacity have not been directly observed in nonprimate species. In this study, we examined the development of neural progenitors in the Chinese tree shrew (Tupaia belangeri chinensis), a lissencephalic animal with closer affinity than rodents to primates. We identified an expansion of the SVZ and the presence of outer radial glial (oRG) cells in the neocortex. We also found that IPCs have the capacity to self-amplify multiple times and therefore serve as major proliferative progenitors. To our knowledge, our study provides the first direct evidence of abundant IPCs with proliferative potential in a nonprimate species, further supporting the key role of IPCs in brain expansion.