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1.
Dev Cell ; 56(23): 3235-3249.e4, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-34741804

RESUMO

Electrical synapses are established between specific neurons and within distinct subcellular compartments, but the mechanisms that direct gap junction assembly in the nervous system are largely unknown. Here, we show that a developmental program tunes cAMP signaling to direct the neuron-specific assembly and placement of electrical synapses in the C. elegans motor circuit. We use live-cell imaging to visualize electrical synapses in vivo and an optogenetic assay to confirm that they are functional. In ventral A class (VA) motor neurons, the UNC-4 transcription factor blocks expression of cAMP antagonists that promote gap junction miswiring. In unc-4 mutants, VA electrical synapses are established with an alternative synaptic partner and are repositioned from the VA axon to soma. cAMP counters these effects by driving gap junction trafficking into the VA axon for electrical synapse assembly. Thus, our experiments establish that cAMP regulates gap junction trafficking for the biogenesis of functional electrical synapses.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , AMP Cíclico/farmacologia , Sinapses Elétricas/fisiologia , Proteínas de Homeodomínio/metabolismo , Neurônios Motores/fisiologia , Frações Subcelulares/fisiologia , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Axônios/efeitos dos fármacos , Axônios/fisiologia , Caenorhabditis elegans/efeitos dos fármacos , Proteínas de Caenorhabditis elegans/genética , Conexinas/genética , Conexinas/metabolismo , Sinapses Elétricas/efeitos dos fármacos , Junções Comunicantes , Regulação da Expressão Gênica , Proteínas de Homeodomínio/genética , Neurônios Motores/efeitos dos fármacos , Frações Subcelulares/efeitos dos fármacos
2.
Sci Rep ; 11(1): 21500, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34728675

RESUMO

The transcriptional repressor called parkin interacting substrate (PARIS; ZNF746) was initially identified as a novel co-substrate of parkin and PINK1 that leads to Parkinson's disease (PD) by disrupting mitochondrial biogenesis through peroxisome proliferator-activated receptor gamma (PPARγ) coactivator -1α (PGC-1α) suppression. Since its initial discovery, growing evidence has linked PARIS to defective mitochondrial biogenesis observed in PD pathogenesis. Yet, dopaminergic (DA) neuron-specific mechanistic underpinnings and genome-wide PARIS binding landscape has not been explored. We employed conditional translating ribosome affinity purification (TRAP) followed by RNA sequencing (TRAP-seq) for transcriptome profiling of DA neurons in transgenic Drosophila lines expressing human PARIS wild type (WT) or mutant (C571A). We also generated genome-wide maps of PARIS occupancy using ChIP-seq in human SH-SY5Y cells. The results demonstrated that PPARγ functions as a master regulator of PARIS-induced molecular changes at the transcriptome level, confirming that PARIS acts primarily on PGC-1α to lead to neurodegeneration in PD. Moreover, we identified that PARIS actively modulates expression of PPARγ target genes by physically binding to the promoter regions. Together, our work revealed how PARIS drives adverse effects on modulation of PPAR-γ associated gene clusters in DA neurons.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Regulação da Expressão Gênica , Neuroblastoma/metabolismo , PPAR gama/metabolismo , Proteínas Repressoras/metabolismo , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Estudo de Associação Genômica Ampla , Humanos , Neuroblastoma/genética , Neuroblastoma/patologia , PPAR gama/genética , RNA-Seq , Proteínas Repressoras/genética , Células Tumorais Cultivadas
3.
Toxicol Lett ; 350: 71-80, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34252508

RESUMO

Sanguinarine, derived from the root of Sanguinaria canadensis, have multiple biological activities, such as antimicrobial, insecticidal, antitumor, anti-inflammatory and anti-angiogenesis effect, but little is known about its toxicity on normal embryonic development. Here, we study the developmental toxicity using zebrafish model. Notably, sanguinarine caused a significant increase of the malformation rate and decrease of hatching rates and body length of zebrafish embryos. Sanguinarine also impaired the normal development of heart, liver and nerve system of zebrafish embryos. Further, the ROS level and MDA concentrations were remarkably increased, while the activity of T-SOD was decreased. In addition, obvious increase of apoptosis were observed by AO staining or TUNEL assay. Further studies showed that the oxidative stress-, apoptosis-related genes were changed, while genes of nrf2 and wnt pathways were inhibited by sangunarine. To sum up, our study will be helpful to understand the adverse effect of sanguinarine on embryonic development and the underlying molecular mechanism.


Assuntos
Apoptose/efeitos dos fármacos , Benzofenantridinas/toxicidade , Isoquinolinas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Peixe-Zebra/embriologia , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Variação Genética , Genótipo , Modelos Animais , Raízes de Plantas/química , Raízes de Plantas/toxicidade , Sanguinaria/química , Sanguinaria/toxicidade
4.
Reproduction ; 162(1): F11-F22, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34042607

RESUMO

Genetic engineering (GE) of livestock initially has been accomplished primarily using pronuclear microinjection into zygotes (1985-1996). The applications of the technology were limited due to low integration efficiency, aberrant transgene expression resulting from random integration and the presence of genetic mosaicism in transgenic founder animals. Despite enormous efforts to established embryonic stem cells (ESCs) for domestic species, the ESC GE technology does not exist for livestock. Development of somatic cell nuclear transfer (SCNT) has bypassed the need in livestock ESCs and revolutionized the field of livestock transgenesis by offering the first cell-based platform for precise genetic manipulation in farm animals. For nearly two decades since the birth of Dolly (1996-2013), SCNT was the only method used for the generation of knockout and knockin livestock. Arrival of CRISPRS/Cas9 system, a new generation of gene-editing technology, gave us an ability to introduce precise genome modifications easily and efficiently. This technological advancement accelerated production of GE livestock by SCNT and reinstated zygote micromanipulation as an important GE approach. The primary advantage of the SCNT technology is the ability to confirm in vitro that the desired genetic modification is present in the somatic cells prior to animal production. The edited cells could also be tested for potential off-target mutations. Additionally, this method eliminates the risk of genetic mosaicism frequently observed following zygote micromanipulation. Despite its low efficiency, SCNT is a well-established procedure in numerous laboratories around the world and will continue to play an important role in the GE livestock field.


Assuntos
Animais Geneticamente Modificados/genética , Núcleo Celular/genética , Clonagem de Organismos/veterinária , Embrião de Mamíferos/citologia , Engenharia Genética , Gado/genética , Técnicas de Transferência Nuclear/veterinária , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Aniversários e Eventos Especiais , Clonagem de Organismos/métodos , Clonagem de Organismos/tendências , Gado/crescimento & desenvolvimento
5.
FASEB J ; 35(5): e21537, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33817834

RESUMO

Cannabidiol (CBD), a phytocannabinoid from the Cannabis sativa plant, exhibits a broad spectrum of potential therapeutic properties for neurodegenerative diseases. An accumulation of amyloid-ß (Aß) protein is one of the most important neuropathology in neurodegenerative diseases like Alzheimer's disease (AD). Data on the effect of CBD on the amelioration of Aß-induced neurite degeneration and its consequences of life and health spans is sparse. This study aimed to investigate the effects of CBD on neurite outgrowth in cells and lifespan and health span in Caenorhabditis elegans (C. elegans). In human SH-SY5Y neuronal cells, CBD prevented neurite lesion induced by Aß1-42 and increased the expression of fatty acid amide hydrolase (FAAH) and cannabinoid receptor 1 (CB1R). Furthermore, CBD both protected the reduction of dendritic spine density and rescued the activity of synaptic Ca2+ /calmodulin-dependent protein kinase II (CaMKII) from Aß1-42 toxicity in primary hippocampal neurons. In C. elegans, we used the transgenic CL2355 strain of C. elegans, which expresses the human Aß peptide throughout the nervous system and found that CBD treatment extended lifespan and improved health span. The neuroprotective effect of CBD was further explored by observing the dopaminergic neurons using transgenic dat-1: GFP strains using the confocal microscope. This study shows that CBD prevents the neurite degeneration induced by Aß, by a mechanism involving CB1R activation, and extends lifespan and improves health span in Aß-overexpressing worms. Our findings support the potential therapeutic approach of CBD for the treatment of AD patients.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Caenorhabditis elegans/crescimento & desenvolvimento , Canabidiol/farmacologia , Longevidade , Neuroblastoma/tratamento farmacológico , Crescimento Neuronal , Receptor CB1 de Canabinoide/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Anticonvulsivantes/farmacologia , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Neurônios/citologia , Neurônios/metabolismo , Fármacos Neuroprotetores , Fosforilação , Receptor CB1 de Canabinoide/genética , Fator de Transcrição STAT3/genética
6.
Reproduction ; 162(1): F23-F32, 2021 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-33852430

RESUMO

SCNT (somatic cell nuclear transfer) has complemented the toolbox of ARTs offering yet another technique to reproduce animals in an unprecedented way. Despite remarkable achievements, SCNT suffers low efficiency, high pregnancy losses and higher than normal stillbirth rates that makes it an expensive technique to reproduce animals. Moreover, due to welfare issues associated with gestation and the newborn offspring, it is banned in some countries. It has become evident that these problems are of epigenetic nature associated with incomplete genome reprogramming, observed more frequently in ruminants and less often and of minor degree in pigs and horses. Genome editing is enormously benefiting from SCNT to turn genome edited cells into animals, even if zygote microinjection of CRISPR/Cas9 will become an alternative route in some occasions. SCNT will also be a route to reprogram somatic cell to pluripotency since bona fide iPSC in livestock are missing while embryonic stem cells have been now established. This opens the way to other technologies like the development of artificial gametes or interspecies nuclear transfer. To strengthen its commercial applications, SCNT will face three major challenges, that is, intellectual property (extremely unclear in genome editing), regulatory approval by the relevant authorities of the resuting potential products and finally, acceptance by the public who will eventually decide with its behavior the life or the death of the technology.


Assuntos
Animais Geneticamente Modificados/genética , Núcleo Celular/genética , Clonagem de Organismos/veterinária , Embrião de Mamíferos/citologia , Genoma , Gado/genética , Técnicas de Transferência Nuclear/veterinária , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Aniversários e Eventos Especiais , Clonagem de Organismos/métodos , Clonagem de Organismos/tendências , Gado/crescimento & desenvolvimento
7.
Bioorg Chem ; 107: 104624, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33465669

RESUMO

Two novel monoterpenoid indole alkaloids (MIAs), gelsechizines A-B (1-2), along with four known ones (3-6) were isolated from the fruits of Gelsemium elegans. Compound 1 features a new carbon skeleton with two additional carbon atoms forming a 4-methylpyridine unit. Their structures with absolute configurations were elucidated by NMR, MS, X-ray diffraction and electronic circular dichroism (ECD) calculations. Compounds 1-3 showed significant anti-inflammatory effects in vivo and in vitro, which may be related to the inhibition of the trecruitment of neutrophils and macrophages as well as the secretion of TNF-α and IL-6. Preliminary structure-activity relationship analysis revealed that the ß-N-acrylate moiety plays an important role in the anti-inflammatory effect.


Assuntos
Anti-Inflamatórios/farmacologia , Gelsemium/química , Macrófagos/efeitos dos fármacos , Alcaloides de Triptamina e Secologanina/química , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Frutas/química , Frutas/metabolismo , Gelsemium/metabolismo , Interleucina-6/metabolismo , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/metabolismo , Espectroscopia de Ressonância Magnética , Camundongos , Conformação Molecular , Neutrófilos/citologia , Neutrófilos/patologia , Células RAW 264.7 , Alcaloides de Triptamina e Secologanina/isolamento & purificação , Alcaloides de Triptamina e Secologanina/farmacologia , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo
8.
Front Endocrinol (Lausanne) ; 11: 578885, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133021

RESUMO

In vertebrate germ cell differentiation, gonadal somatic cells and germ cells are closely related. By analyzing this relationship, it has recently been reported in mammals that primordial germ cells (PGCs), induced from pluripotent stem cells and germline stem cells, can differentiate into functional gametes when co-cultured in vitro with fetal gonadal somatic cells. In some fish species, differentiation into functional sperm by reaggregation or co-culture of gonadal somatic cells and germ cells has also been reported; however, the relationship between gonadal somatic cells and germ cells in these species is not well-understood. Here, we report the transcriptional regulation of Müllerian inhibiting substance (MIS) and the establishment of a gonadal somatic cell line using mis-GFP transgenic fish, in medaka (Oryzias latipes)-a fish model which offers many advantages for molecular genetics. MIS is a glycoprotein belonging to the transforming growth factor ß superfamily. In medaka, mis mRNA is expressed in gonadal somatic cells of both sexes before sex differentiation, and MIS regulates the proliferation of germ cells during this period. Using luciferase assays, we found that steroidogenic factor 1 (SF1) and liver receptor homolog 1 (LRH1) activate medaka mis gene transcription, probably by binding to the mis promoter. We also report that mis-GFP transgenic medaka emit GFP fluorescence specific to gonadal somatic cells in the gonads. By fusing Sertoli cells from transgenic medaka with a cell line derived from medaka hepatoma cancer, we produced a hybridoma cell line that expresses gonadal somatic cell-specific markers, including Sertoli and Leydig cell markers. Moreover, embryonic PGCs co-cultured with the established hybridoma, as feeder cells, proliferated and formed significant colonies after 1 week. PGCs cultured for 3 weeks expressed a germ cell marker dnd, as well as the meiotic markers sycp1 and sycp3. Thus, we here provide the first evidence in teleosts that we have successfully established a gonadal somatic cell-derived hybridoma that can induce both the proliferation and meiosis of germ cells.


Assuntos
Animais Geneticamente Modificados/metabolismo , Hormônio Antimülleriano/metabolismo , Proteínas de Peixes/metabolismo , Regulação da Expressão Gênica , Células Germinativas/metabolismo , Gônadas/metabolismo , Oryzias/metabolismo , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Hormônio Antimülleriano/genética , Diferenciação Celular , Células Cultivadas , Proteínas de Peixes/genética , Células Germinativas/citologia , Gônadas/citologia , Oryzias/genética , Oryzias/crescimento & desenvolvimento
10.
PLoS One ; 15(7): e0235433, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32726316

RESUMO

ADP-ribosylhydrolase-like 1 (Adprhl1) is a pseudoenzyme expressed in the developing heart myocardium of all vertebrates. In the amphibian Xenopus laevis, knockdown of the two cardiac Adprhl1 protein species (40 and 23 kDa) causes failure of chamber outgrowth but this has only been demonstrated using antisense morpholinos that interfere with RNA-splicing. Transgenic production of 40 kDa Adprhl1 provides only part rescue of these defects. CRISPR/Cas9 technology now enables targeted mutation of the adprhl1 gene in G0-generation embryos with routine cleavage of all alleles. Testing multiple gRNAs distributed across the locus reveals exonic locations that encode critical amino acids for Adprhl1 function. The gRNA recording the highest frequency of a specific ventricle outgrowth phenotype directs Cas9 cleavage of an exon 6 sequence, where microhomology mediated end-joining biases subsequent DNA repairs towards three small in-frame deletions. Mutant alleles encode discrete loss of 1, 3 or 4 amino acids from a di-arginine (Arg271-Arg272) containing peptide loop at the centre of the ancestral ADP-ribosylhydrolase site. Thus despite lacking catalytic activity, it is the modified (adenosine-ribose) substrate binding cleft of Adprhl1 that fulfils an essential role during heart formation. Mutation results in striking loss of myofibril assembly in ventricle cardiomyocytes. The defects suggest Adprhl1 participation from the earliest stage of cardiac myofibrillogenesis and are consistent with previous MO results and Adprhl1 protein localization to actin filament Z-disc boundaries. A single nucleotide change to the gRNA sequence renders it inactive. Mice lacking Adprhl1 exons 3-4 are normal but production of the smaller ADPRHL1 species is unaffected, providing further evidence that cardiac activity is concentrated at the C-terminal protein portion.


Assuntos
Ventrículos do Coração/crescimento & desenvolvimento , Coração/crescimento & desenvolvimento , Desenvolvimento Muscular/genética , N-Glicosil Hidrolases/genética , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Catálise , Domínio Catalítico/genética , Coração/fisiopatologia , Ventrículos do Coração/patologia , Humanos , Camundongos , Camundongos Knockout , Morfolinos/genética , Oligodesoxirribonucleotídeos Antissenso/genética , Oligodesoxirribonucleotídeos Antissenso/farmacologia , Organogênese/genética , Xenopus laevis/genética , Xenopus laevis/crescimento & desenvolvimento
11.
Development ; 147(11)2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32439759

RESUMO

The anchor cell (AC) in C. elegans secretes an epidermal growth factor (EGF) homolog that induces adjacent vulval precursor cells (VPCs) to differentiate. The EGF receptor in the nearest VPC sequesters the limiting EGF amounts released by the AC to prevent EGF from spreading to distal VPCs. Here, we show that not only EGFR localization in the VPCs but also EGF polarity in the AC is necessary for robust fate specification. The AC secretes EGF in a directional manner towards the nearest VPC. Loss of AC polarity causes signal spreading and, when combined with MAPK pathway hyperactivation, the ectopic induction of distal VPCs. In a screen for genes preventing distal VPC induction, we identified sra-9 and nlp-26 as genes specifically required for polarized EGF secretion. sra-9(lf) and nlp-26(lf) mutants exhibit errors in vulval fate specification, reduced precision in VPC to AC alignment and increased variability in MAPK activation. sra-9 encodes a seven-pass transmembrane receptor acting in the AC and nlp-26 a neuropeptide-like protein expressed in the VPCs. SRA-9 and NLP-26 may transduce a feedback signal to channel EGF secretion towards the nearest VPC.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Fator de Crescimento Epidérmico/metabolismo , Vulva/metabolismo , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Sistemas CRISPR-Cas/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/antagonistas & inibidores , Proteínas de Caenorhabditis elegans/genética , Fator de Crescimento Epidérmico/antagonistas & inibidores , Fator de Crescimento Epidérmico/genética , Receptores ErbB/metabolismo , Feminino , Edição de Genes , Larva/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutagênese , Netrinas/genética , Netrinas/metabolismo , Interferência de RNA , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/metabolismo , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo , Vulva/citologia , Vulva/crescimento & desenvolvimento , Proteínas Ativadoras de ras GTPase/antagonistas & inibidores , Proteínas Ativadoras de ras GTPase/genética , Proteínas Ativadoras de ras GTPase/metabolismo
12.
Development ; 147(12)2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32439761

RESUMO

The development of the biliary system is a complex yet poorly understood process, with relevance to multiple diseases, including biliary atresia, choledochal cysts and gallbladder agenesis. We present here a crucial role for Hippo-Yap/Taz signaling in this context. Analysis of sav1 mutant zebrafish revealed dysplastic morphology and expansion of both intrahepatic and extrahepatic biliary cells, and ultimately larval lethality. Biliary dysgenesis, but not larval lethality, is driven primarily by Yap signaling. Re-expression of Sav1 protein in sav1-/- hepatocytes is able to overcome these initial deficits and allows sav1-/- fish to survive, suggesting cell non-autonomous signaling from hepatocytes. Examination of sav1-/- rescued adults reveals loss of gallbladder and formation of dysplastic cell masses expressing biliary markers, suggesting roles for Hippo signaling in extrahepatic biliary carcinomas. Deletion of stk3 revealed that the phenotypes observed in sav1 mutant fish function primarily through canonical Hippo signaling and supports a role for phosphatase PP2A, but also suggests Sav1 has functions in addition to facilitating Stk3 activity. Overall, this study defines a role for Hippo-Yap signaling in the maintenance of both intra- and extrahepatic biliary ducts.


Assuntos
Sistema Biliar/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transativadores/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Aciltransferases , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Sistema Biliar/anatomia & histologia , Sistema Biliar/crescimento & desenvolvimento , Sistemas CRISPR-Cas/genética , Hidrolases de Éster Carboxílico/metabolismo , Vesícula Biliar/anatomia & histologia , Vesícula Biliar/crescimento & desenvolvimento , Vesícula Biliar/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Fígado/anatomia & histologia , Fígado/metabolismo , Fenótipo , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Serina-Treonina Quinase 3 , Transdução de Sinais , Transativadores/genética , Fatores de Transcrição/genética , Proteínas de Sinalização YAP , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/deficiência , Proteínas de Peixe-Zebra/genética
13.
Development ; 147(12)2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32467235

RESUMO

The transcription factor Stat3 is required for proliferation and pluripotency of embryonic stem cells; we have prepared and characterized fluorescent Stat3-reporter zebrafish based on repeats of minimal responsive elements. These transgenic lines mimic in vivo Stat3 expression patterns and are responsive to exogenous Stat3; notably, fluorescence is inhibited by both stat3 knockout and IL6/Jak/STAT inhibitors. At larval stages, Stat3 reporter activity correlates with proliferating regions of the brain, haematopoietic tissue and intestine. In the adult gut, the reporter is active in sparse proliferating cells, located at the base of intestinal folds, expressing the stemness marker sox9b and having the morphology of mammalian crypt base columnar cells; noteworthy, zebrafish stat3 mutants show defects in intestinal folding. Stat3 reporter activity in the gut is abolished with mutation of T cell factor 4 (Tcf7l2), the intestinal mediator of Wnt/ß-catenin-dependent transcription. The Wnt/ß-catenin dependence of Stat3 activity in the gut is confirmed by abrupt expansion of Stat3-positive cells in intestinal adenomas of apc heterozygotes. Our findings indicate that Jak/Stat3 signalling is needed for intestinal stem cell maintenance and possibly crucial in controlling Wnt/ß-catenin-dependent colorectal cancer cell proliferation.


Assuntos
Mucosa Intestinal/metabolismo , Fator de Transcrição STAT3/metabolismo , Via de Sinalização Wnt , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Intestinos/crescimento & desenvolvimento , Intestinos/fisiologia , Janus Quinase 1 , Larva/crescimento & desenvolvimento , Larva/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Fatores de Transcrição SOX9/metabolismo , Fator de Transcrição STAT3/antagonistas & inibidores , Fator de Transcrição STAT3/deficiência , Fator de Transcrição STAT3/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/deficiência , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/metabolismo , Transcrição Gênica/efeitos dos fármacos , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Peixe-Zebra/crescimento & desenvolvimento , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/deficiência , Proteínas de Peixe-Zebra/genética , beta Catenina/metabolismo
14.
Hum Mol Genet ; 29(4): 674-688, 2020 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-31943010

RESUMO

Huntington's disease (HD) is caused by an expansion of a poly glutamine (polyQ) stretch in the huntingtin protein (HTT) that is necessary to cause pathology and formation of HTT aggregates. Here we ask whether expanded polyQ is sufficient to cause pathology and aggregate formation. By addressing the sufficiency question, one can identify cellular processes and structural parameters that influence HD pathology and HTT subcellular behavior (i.e. aggregation state and subcellular location). Using Drosophila, we compare the effects of expressing mutant full-length human HTT (fl-mHTT) to the effects of mutant human HTTexon1 and to two commonly used synthetic fragments, HTT171 and shortstop (HTT118). Expanded polyQ alone is not sufficient to cause inclusion formation since full-length HTT and HTTex1 with expanded polyQ are both toxic although full-length HTT remains diffuse while HTTex1 forms inclusions. Further, inclusions are not sufficient to cause pathology since HTT171-120Q forms inclusions but is benign and co-expression of HTT171-120Q with non-aggregating pathogenic fl-mHTT recruits fl-mHTT to aggregates and rescues its pathogenicity. Additionally, the influence of sequences outside the expanded polyQ domain is revealed by finding that small modifications to the HTT118 or HTT171 fragments can dramatically alter their subcellular behavior and pathogenicity. Finally, mutant HTT subcellular behavior is strongly modified by different cell and tissue environments (e.g. fl-mHTT appears as diffuse nuclear in one tissue and diffuse cytoplasmic in another but toxic in both). These observations underscore the importance of cellular and structural context for the interpretation and comparison of experiments using different fragments and tissues to report the effects of expanded polyQ.


Assuntos
Núcleo Celular/patologia , Drosophila melanogaster/crescimento & desenvolvimento , Proteína Huntingtina/genética , Mutação , Neurônios/patologia , Peptídeos/genética , Traqueia/patologia , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , Humanos , Proteína Huntingtina/metabolismo , Doença de Huntington/genética , Doença de Huntington/metabolismo , Doença de Huntington/patologia , Corpos de Inclusão , Masculino , Neurônios/metabolismo , Traqueia/metabolismo
15.
Sci Rep ; 9(1): 9819, 2019 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-31285449

RESUMO

5'adenosine monophosphate-activated protein kinase (AMPK) is a master regulator of energy homeostasis in eukaryotes. This study identified expansions in the AMPK-α, -ß and -γ families of salmonid fishes due to a history of genome duplication events, including five novel salmonid-specific AMPK subunit gene paralogue pairs. We tested the hypothesis that the expanded AMPK gene system of salmonids is transcriptionally regulated by growth and immunological status. As a model, we studied immune-stimulated coho salmon (Oncorhynchus kisutch) from three experiment groups sharing the same genetic background, but showing highly-divergent growth rates and nutritional status. Specifically, we compared wild-type and GH-transgenic fish, the latter achieving either enhanced or wild-type growth rate via ration manipulation. Transcript levels for the fifteen unique salmonid AMPK subunit genes were quantified in skeletal muscle after stimulation with bacterial or viral mimics to alter immune status. These analyses revealed a constitutive up-regulation of several AMPK-α and -γ subunit-encoding genes in GH-transgenic fish achieving accelerated growth. Further, immune stimulation caused a decrease in the expression of several AMPK subunit-encoding genes in GH-transgenic fish specifically. The dynamic expression responses observed suggest a role for the AMPK system in balancing energetic investment into muscle growth according to immunological status in salmonid fishes.


Assuntos
Proteínas Quinases Ativadas por AMP/genética , Hormônio do Crescimento/genética , Músculo Esquelético/metabolismo , Oncorhynchus kisutch/crescimento & desenvolvimento , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/fisiologia , Evolução Molecular , Proteínas de Peixes/genética , Duplicação Gênica , Hormônio do Crescimento/metabolismo , Homeostase , Estado Nutricional , Oncorhynchus kisutch/genética , Oncorhynchus kisutch/fisiologia , Filogenia , Especificidade da Espécie
16.
Int J Dev Biol ; 63(6-7): 259-270, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31250909

RESUMO

Mechanisms of programmed cell death differ between animals, plants and fungi. In animals, apoptotic cell death depends on caspases and Bcl-2 family proteins. These protein families are only found in multicellular animals, including cnidarians, insects and mammals. In contrast, members of the TMBIM-family of transmembrane proteins are conserved across all eukaryotes. Sequence comparisons of cell death related proteins between phyla indicate strong conservation of the genes involved. However, often it is not known whether this is paralleled by conservation of function. Here we present the first study to support an anti-apoptotic function of Bcl-2 like proteins in the cnidarian Hydra within a physiological context. We used transgenic Hydra expressing GFP-tagged HyBcl-2-like 4 protein in epithelial cells. The protein was localised to mitochondria and able to protect Hydra epithelial cells from apoptosis induced by either the PI(3) kinase inhibitor wortmannin or by starvation. Moreover, we identified members of the TMBIM-family in Hydra including HyBax-Inhibitor-1, HyLifeguard-1a and -1b and HyLifeguard 4. Expressing these TMBIM-family members in Hydra and human HEK cells, we found HyBax-inhibitor-1 protein localised to ER-membranes and HyLifeguard-family members localised to the plasma membrane and Golgi-vesicles. Moreover, HyBax-inhibitor-1 protected human cells from camptothecin induced apoptosis. This work illustrates that the investigated Bcl-2- and TMBIM-family members represent evolutionarily conserved mitochondrial, ER, Golgi and plasma membrane proteins with anti-apoptotic functions. The participation of ER and Golgi proteins in the regulation of programmed cell death might be a very ancient feature.


Assuntos
Animais Geneticamente Modificados/metabolismo , Apoptose , Regulação da Expressão Gênica , Hydra/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Células HEK293 , Humanos , Hydra/efeitos dos fármacos , Hydra/genética , Imunossupressores/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Homologia de Sequência , Inanição , Wortmanina/farmacologia , Proteína X Associada a bcl-2/genética
17.
Molecules ; 24(7)2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30939726

RESUMO

Bombyx mori nucleopolyhedrovirus (BmNPV) is the most prevalent threat to silkworms. Hence, there is a need for antiviral agents in sericulture. The PI3K-Akt pathway is essential for the efficient replication of the baculovirus. In an attempt to screen antiviral drugs against BmNPV, we summarized the commercial compounds targeting PI3K-Akt and selected the following seven oral drugs for further analyses: afuresertib, AZD8835, AMG319, HS173, AS605240, GDC0941, and BEZ235. Cell viability assay revealed that the cytotoxicity of these drugs at 10 µM concentration was not strong. Viral fluorescence observation and qPCR analysis showed that these candidate drugs significantly inhibited BmNPV in BmE cells. Only AMG319 and AZD8835 inhibited viral proliferation in silkworm larvae. The mortality of AZD8835-treated silkworms was lower than that of the control silkworms. Western blotting showed that AMG319 and AZD8835 decreased p-Akt expression after BmNPV infection. These results suggest that AZD8835 has application potential in sericulture.


Assuntos
Animais Geneticamente Modificados/crescimento & desenvolvimento , Antivirais/farmacologia , Bombyx/crescimento & desenvolvimento , Nucleopoliedrovírus/efeitos dos fármacos , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Replicação Viral/efeitos dos fármacos , Animais , Animais Geneticamente Modificados/virologia , Bombyx/efeitos dos fármacos , Bombyx/virologia , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/virologia
18.
Sci Rep ; 9(1): 3594, 2019 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-30837605

RESUMO

The mechanisms underlying zebrafish pancreatic islet vascularization have not been well characterized. We sought to determine the angiogenic factors responsible for islet vascularization and assess whether an absence of endothelial cells affects beta-cell and alpha-cell formation. We used a double transgenic zebrafish Tg(fli1:EGFP; insa:tagRFP) to label endothelial cells and beta-cells, respectively. Beta-cells developed adjacent to endothelial cells and by 72 hours post fertilization (hpf) the zebrafish pancreatic islet was highly vascularized. Zebrafish beta-cells express vascular endothelial growth factors (vegf), vegfaa and vegfab. Double knockdown of vegfaa and vegfab or the primary Vegfa receptors (Vegfr2), kdr and kdrl, resulted in vessel deficient islets. While beta-cell and alpha-cell numbers remained unchanged in vessel deficient islets, insulina expression was downregulated relative to controls. Vegfaa/Vegfab-Vegfr2 signaling is necessary for proper islet vessel development, but not for the initial formation of beta-cells and alpha-cells.


Assuntos
Animais Geneticamente Modificados/crescimento & desenvolvimento , Células Secretoras de Glucagon/citologia , Células Secretoras de Insulina/citologia , Neovascularização Fisiológica , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/metabolismo , Células Secretoras de Glucagon/metabolismo , Células Secretoras de Insulina/metabolismo , Transdução de Sinais , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética
19.
PLoS Genet ; 15(1): e1007852, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30645584

RESUMO

Most organs of multicellular organisms are built from epithelial tubes. To exert their functions, tubes rely on apico-basal polarity, on junctions, which form a barrier to separate the inside from the outside, and on a proper lumen, required for gas or liquid transport. Here we identify apnoia (apn), a novel Drosophila gene required for tracheal tube elongation and lumen stability at larval stages. Larvae lacking Apn show abnormal tracheal inflation and twisted airway tubes, but no obvious defects in early steps of tracheal maturation. apn encodes a transmembrane protein, primarily expressed in the tracheae, which exerts its function by controlling the localization of Crumbs (Crb), an evolutionarily conserved apical determinant. Apn physically interacts with Crb to control its localization and maintenance at the apical membrane of developing airways. In apn mutant tracheal cells, Crb fails to localize apically and is trapped in retromer-positive vesicles. Consistent with the role of Crb in apical membrane growth, RNAi-mediated knockdown of Crb results in decreased apical surface growth of tracheal cells and impaired axial elongation of the dorsal trunk. We conclude that Apn is a novel regulator of tracheal tube expansion in larval tracheae, the function of which is mediated by Crb.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas de Membrana/genética , Traqueia/crescimento & desenvolvimento , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Polaridade Celular/genética , Drosophila melanogaster/crescimento & desenvolvimento , Células Epiteliais/metabolismo , Mutação , Traqueia/metabolismo
20.
Cell Rep ; 25(2): 437-448, 2018 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-30304683

RESUMO

Tankyrase (Tnks) transfers poly(ADP-ribose) on substrates. Whereas studies have highlighted the pivotal roles of Tnks in cancer, cherubism, systemic sclerosis, and viral infection, the requirement for Tnks under physiological contexts remains unclear. Here, we report that the loss of Tnks or its muscle-specific knockdown impairs lifespan, stress tolerance, and energy homeostasis in adult Drosophila. We find that Tnks is a positive regulator in the JNK signaling pathway, and modest alterations in the activity of JNK signaling can strengthen or suppress the Tnks mutant phenotypes. We further identify JNK as a direct substrate of Tnks. Although Tnks-dependent poly-ADP-ribosylation is tightly coupled to proteolysis in the proteasome, we demonstrate that Tnks initiates degradation-independent ubiquitination on two lysine residues of JNK to promote its kinase activity and in vivo functions. Our study uncovers a type of posttranslational modification of Tnks substrates and provides insights into Tnks-mediated physiological roles.


Assuntos
Proteínas de Drosophila/metabolismo , Drosophila melanogaster/crescimento & desenvolvimento , Longevidade , Lisina/química , MAP Quinase Quinase 4/metabolismo , Estresse Oxidativo , Tanquirases/metabolismo , Ubiquitinação , Animais , Animais Geneticamente Modificados/genética , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Feminino , MAP Quinase Quinase 4/genética , Masculino , Poli ADP Ribosilação , Processamento de Proteína Pós-Traducional , Proteólise , Estresse Fisiológico , Tanquirases/genética
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