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1.
Zool Res ; 42(5): 637-649, 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34472225

RESUMO

The insect brain is the central part of the neurosecretory system, which controls morphology, physiology, and behavior during the insect's lifecycle. Lepidoptera are holometabolous insects, and their brains develop during the larval period and metamorphosis into the adult form. As the only fully domesticated insect, the Lepidoptera silkworm Bombyx mori experienced changes in larval brain morphology and certain behaviors during the domestication process. Hormonal regulation in insects is a key factor in multiple processes. However, how juvenile hormone (JH) signals regulate brain development in Lepidoptera species, especially in the larval stage, remains elusive. We recently identified the JH receptor Methoprene tolerant 1 ( Met1) as a putative domestication gene. How artificial selection on Met1 impacts brain and behavioral domestication is another important issue addressing Darwin's theory on domestication. Here, CRISPR/Cas9-mediated knockout of Bombyx Met1 caused developmental retardation in the brain, unlike precocious pupation of the cuticle. At the whole transcriptome level, the ecdysteroid (20-hydroxyecdysone, 20E) signaling and downstream pathways were overactivated in the mutant cuticle but not in the brain. Pathways related to cell proliferation and specialization processes, such as extracellular matrix (ECM)-receptor interaction and tyrosine metabolism pathways, were suppressed in the brain. Molecular evolutionary analysis and in vitro assay identified an amino acid replacement located in a novel motif under positive selection in B. mori, which decreased transcriptional binding activity. The B. mori MET1 protein showed a changed structure and dynamic features, as well as a weakened co-expression gene network, compared with B. mandarina. Based on comparative transcriptomic analyses, we proposed a pathway downstream of JH signaling (i.e., tyrosine metabolism pathway) that likely contributed to silkworm larval brain development and domestication and highlighted the importance of the biogenic amine system in larval evolution during silkworm domestication.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Bombyx/metabolismo , Proteínas de Insetos/metabolismo , Hormônios Juvenis/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Bombyx/crescimento & desenvolvimento , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Sistemas CRISPR-Cas , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento , Genótipo , Proteínas de Insetos/genética , Tegumento Comum/fisiologia , Larva/crescimento & desenvolvimento , Larva/metabolismo , Filogenia , Conformação Proteica
2.
Nat Commun ; 12(1): 4797, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376651

RESUMO

Sutures separate the flat bones of the skull and enable coordinated growth of the brain and overlying cranium. The coronal suture is most commonly fused in monogenic craniosynostosis, yet the unique aspects of its development remain incompletely understood. To uncover the cellular diversity within the murine embryonic coronal suture, we generated single-cell transcriptomes and performed extensive expression validation. We find distinct pre-osteoblast signatures between the bone fronts and periosteum, a ligament-like population above the suture that persists into adulthood, and a chondrogenic-like population in the dura mater underlying the suture. Lineage tracing reveals an embryonic Six2+ osteoprogenitor population that contributes to the postnatal suture mesenchyme, with these progenitors being preferentially affected in a Twist1+/-; Tcf12+/- mouse model of Saethre-Chotzen Syndrome. This single-cell atlas provides a resource for understanding the development of the coronal suture and the mechanisms for its loss in craniosynostosis.


Assuntos
Suturas Cranianas/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Osteogênese/genética , Análise de Célula Única/métodos , Transcriptoma/genética , Acrocefalossindactilia/embriologia , Acrocefalossindactilia/genética , Acrocefalossindactilia/patologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Suturas Cranianas/citologia , Suturas Cranianas/embriologia , Dura-Máter/citologia , Dura-Máter/embriologia , Dura-Máter/metabolismo , Mesoderma/citologia , Mesoderma/embriologia , Mesoderma/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Osteoblastos/citologia , Osteoblastos/metabolismo , RNA-Seq/métodos , Crânio/citologia , Crânio/embriologia , Crânio/metabolismo , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismo
3.
Int J Mol Sci ; 22(16)2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34445454

RESUMO

The basic helix-loop-helix (bHLH) family of transcription factors is one of the most significant and biggest in plants. It is involved in the regulation of both growth and development, as well as stress response. Numerous members of the bHLH family have been found and characterized in woody plants in recent years. However, no systematic study of the bHLH gene family has been published for Hibiscus hamabo Sieb. et Zucc. In this research, we identified 162 bHLH proteins (HhbHLHs) from the genomic and transcriptomic datasets of H. hamabo, which were phylogenetically divided into 19 subfamilies. According to a gene structural study, the number of exon-introns in HhbHLHs varied between zero and seventeen. MEME research revealed that the majority of HhbHLH proteins contained three conserved motifs, 1, 4, and 5. The examination of promoter cis-elements revealed that the majority of HhbHLH genes had several cis-elements involved in plant growth and development and abiotic stress responses. In addition, the overexpression of HhbHLH2 increased salt and drought stress tolerance in Arabidopsis.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Regulação da Expressão Gênica de Plantas , Hibiscus , Proteínas de Plantas , Estresse Salino , Fatores de Transcrição Hélice-Alça-Hélice Básicos/biossíntese , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Desidratação/genética , Desidratação/metabolismo , Estudo de Associação Genômica Ampla , Hibiscus/genética , Hibiscus/metabolismo , Proteínas de Plantas/biossíntese , Proteínas de Plantas/genética
4.
Am J Hum Genet ; 108(9): 1611-1630, 2021 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-34343493

RESUMO

Genome-wide association studies (GWASs) have identified a melanoma-associated locus on chromosome band 7p21.1 with rs117132860 as the lead SNP and a secondary independent signal marked by rs73069846. rs117132860 is also associated with tanning ability and cutaneous squamous cell carcinoma (cSCC). Because ultraviolet radiation (UVR) is a key environmental exposure for all three traits, we investigated the mechanisms by which this locus contributes to melanoma risk, focusing on cellular response to UVR. Fine-mapping of melanoma GWASs identified four independent sets of candidate causal variants. A GWAS region-focused Capture-C study of primary melanocytes identified physical interactions between two causal sets and the promoter of the aryl hydrocarbon receptor (AHR). Subsequent chromatin state annotation, eQTL, and luciferase assays identified rs117132860 as a functional variant and reinforced AHR as a likely causal gene. Because AHR plays critical roles in cellular response to dioxin and UVR, we explored links between this SNP and AHR expression after both 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and ultraviolet B (UVB) exposure. Allele-specific AHR binding to rs117132860-G was enhanced following both, consistent with predicted weakened AHR binding to the risk/poor-tanning rs117132860-A allele, and allele-preferential AHR expression driven from the protective rs117132860-G allele was observed following UVB exposure. Small deletions surrounding rs117132860 introduced via CRISPR abrogates AHR binding, reduces melanocyte cell growth, and prolongs growth arrest following UVB exposure. These data suggest AHR is a melanoma susceptibility gene at the 7p21.1 risk locus and rs117132860 is a functional variant within a UVB-responsive element, leading to allelic AHR expression and altering melanocyte growth phenotypes upon exposure.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma de Células Escamosas/genética , Cromossomos Humanos Par 7 , Loci Gênicos , Melanócitos/metabolismo , Melanoma/genética , Receptores de Hidrocarboneto Arílico/genética , Neoplasias Cutâneas/genética , Alelos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinogênese/genética , Carcinogênese/metabolismo , Carcinogênese/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Cromatina/química , Cromatina/metabolismo , Regulação da Expressão Gênica , Predisposição Genética para Doença , Genoma Humano , Estudo de Associação Genômica Ampla , Humanos , Melanócitos/efeitos dos fármacos , Melanócitos/patologia , Melanócitos/efeitos da radiação , Melanoma/metabolismo , Melanoma/patologia , Dibenzodioxinas Policloradas/toxicidade , Polimorfismo de Nucleotídeo Único , Cultura Primária de Células , Regiões Promotoras Genéticas , Receptores de Hidrocarboneto Arílico/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Banho de Sol , Raios Ultravioleta/efeitos adversos
5.
Int J Mol Sci ; 22(16)2021 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-34445257

RESUMO

The production of pancreatic ß cells is the most challenging step for curing diabetes using next-generation treatments. Adult pancreatic endocrine cells are thought to be maintained by the self-duplication of differentiated cells, and pancreatic endocrine neogenesis can only be observed when the tissue is severely damaged. Experimentally, this can be performed using a method named partial duct ligation (PDL). As the success rate of PDL surgery is low because of difficulties in identifying the pancreatic duct, we previously proposed a method for fluorescently labeling the duct in live animals. Using this method, we performed PDL on neurogenin3 (Ngn3)-GFP transgenic mice to determine the origin of endocrine precursor cells and evaluate their potential to differentiate into multiple cell types. Ngn3-activated cells, which were marked with GFP, appeared after PDL operation. Because some GFP-positive cells were aligned proximally to the duct, we hypothesized that Ngn3-positive cells arise from the pancreatic duct. Therefore, we next developed an in vitro pancreatic duct culture system using Ngn3-GFP mice and examined whether Ngn3-positive cells emerge from this duct. We observed GFP expressions in ductal organoid cultures. GFP expressions were correlated with Ngn3 expressions and endocrine cell lineage markers. Interestingly, tuft cell markers were also correlated with GFP expressions. Our results demonstrate that in adult mice, Ngn3-positive endocrine precursor cells arise from the pancreatic ducts both in vivo and in vitro experiments indicating that the pancreatic duct could be a potential donor for therapeutic use.


Assuntos
Antígenos de Diferenciação/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Células Secretoras de Insulina/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ductos Pancreáticos/metabolismo , Células-Tronco/metabolismo , Animais , Antígenos de Diferenciação/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células Secretoras de Insulina/citologia , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Organoides/citologia , Organoides/metabolismo , Ductos Pancreáticos/citologia , Células-Tronco/citologia
6.
Stem Cell Res ; 54: 102386, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34229210

RESUMO

Neurogenin 2 encodes a neural-specific transcription factor (NGN2) able to drive neuronal fate on somatic and stem cells. NGN2 is expressed in neural progenitors within the developing central and peripheral nervous systems. Overexpression of NGN2 in human induced pluripotent stem cells (hiPSCs) or human embryonic stem cells has been shown to efficiently trigger conversion to neurons. Here we describe two gene-edited hiPSC lines harbouring a doxycycline (DOX)-inducible cassette in the AAVS1 locus driving expression of NGN2 (BIONi010-C-13) or NGN2-T2A-GFP (BIONi010-C-15). By introducing NGN2-expressing cassette, we reduce variability associated with conventional over-expression methods such as viral transduction, making these lines amenable for scale-up production and screening processes. DOX-treated hiPSCs convert to neural phenotype within one week and display the expression of structural neuronal markers such as Beta-III tubulin and tau. We performed functional characterization of NGN2-neurons co-cultured with hiPSC-derived astrocytes in a "fully-humanized" set up. Passive properties of NGN2-neurons were indistinguishable from mouse primary cells while displaying variable activity in extracellular recordings performed in multi-electrode arrays (MEAs). We demonstrate that hiPSC-derived astrocytes and neurons can be co-cultured and display functional properties comparable to the gold standard used in electrophysiology. Both lines are globally available via EBiSC repository at https://cells.ebisc.org/.


Assuntos
Células-Tronco Pluripotentes Induzidas , Animais , Astrócitos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular , Células Cultivadas , Técnicas de Cocultura , Humanos , Camundongos , Neurônios
7.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281206

RESUMO

The basic helix-loop-helix (bHLH) transcription factor family is one of the largest transcription factor gene families in Arabidopsis thaliana, and contains a bHLH motif that is highly conserved throughout eukaryotic organisms. Members of this family have two conserved motifs, a basic DNA binding region and a helix-loop-helix (HLH) region. These proteins containing bHLH domain usually act as homo- or heterodimers to regulate the expression of their target genes, which are involved in many physiological processes and have a broad range of functions in biosynthesis, metabolism and transduction of plant hormones. Although there are a number of articles on different aspects to provide detailed information on this family in plants, an overall summary is not available. In this review, we summarize various aspects of related studies that provide an overview of insights into the pleiotropic regulatory roles of these transcription factors in plant growth and development, stress response, biochemical functions and the web of signaling networks. We then provide an overview of the functional profile of the bHLH family and the regulatory mechanisms of other proteins.


Assuntos
Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Sequência de Aminoácidos , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Expressão Gênica , Genoma de Planta , Sequências Hélice-Alça-Hélice , Família Multigênica , Filogenia , Proteínas de Plantas/genética , Análise de Sequência de DNA/métodos , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
Int J Mol Sci ; 22(14)2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34299015

RESUMO

Synthetic cathinones have gained popularity among young drug users and are widely used in the clandestine market. While the cathinone-induced behavioral profile has been extensively investigated, information on their neuroplastic effects is still rather fragmentary. Accordingly, we have exposed male mice to a single injection of MDPV and α-PVP and sacrificed the animals at different time points (i.e., 30 min, 2 h, and 24 h) to have a rapid readout of the effect of these psychostimulants on neuroplasticity in the frontal lobe and hippocampus, two reward-related brain regions. We found that a single, low dose of MDPV or α-PVP is sufficient to alter the expression of neuroplastic markers in the adult mouse brain. In particular, we found increased expression of the transcription factor Npas4, increased ratio between the vesicular GABA transporter and the vesicular glutamate transporter together with changes in the expression of the neurotrophin Bdnf, confirming the widespread impact of these cathinones on brain plasticity. To sum up, exposure to low dose of cathinones can impair cortical and hippocampal homeostasis, suggesting that abuse of these cathinones at much higher doses, as it occurs in humans, could have an even more profound impact on neuroplasticity.


Assuntos
Alcaloides/farmacologia , Lobo Frontal/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Benzodioxóis/farmacologia , Fator Neurotrófico Derivado do Encéfalo/genética , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Estimulantes do Sistema Nervoso Central/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Lobo Frontal/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Pentanonas/farmacologia , Pirrolidinas/farmacologia , Ácido gama-Aminobutírico/metabolismo
9.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201511

RESUMO

Diabetes is a metabolic disease that involves the death or dysfunction of the insulin-secreting ß cells in the pancreas. Consequently, most diabetes research is aimed at understanding the molecular and cellular bases of pancreatic development, islet formation, ß-cell survival, and insulin secretion. Complex interactions of signaling pathways and transcription factor networks regulate the specification, growth, and differentiation of cell types in the developing pancreas. Many of the same regulators continue to modulate gene expression and cell fate of the adult pancreas. The transcription factor NEUROD1 is essential for the maturation of ß cells and the expansion of the pancreatic islet cell mass. Mutations of the Neurod1 gene cause diabetes in humans and mice. However, the different aspects of the requirement of NEUROD1 for pancreas development are not fully understood. In this study, we investigated the role of NEUROD1 during the primary and secondary transitions of mouse pancreas development. We determined that the elimination of Neurod1 impairs the expression of key transcription factors for α- and ß-cell differentiation, ß-cell proliferation, insulin production, and islets of Langerhans formation. These findings demonstrate that the Neurod1 deletion altered the properties of α and ß endocrine cells, resulting in severe neonatal diabetes, and thus, NEUROD1 is required for proper activation of the transcriptional network and differentiation of functional α and ß cells.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ilhotas Pancreáticas/citologia , Pâncreas/citologia , Pâncreas/embriologia , Animais , Animais Recém-Nascidos , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Diabetes Mellitus/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Insulina/metabolismo , Células Secretoras de Insulina/citologia , Células Secretoras de Insulina/metabolismo , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/ultraestrutura , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
10.
Stem Cell Res ; 54: 102432, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34214899

RESUMO

Aryl hydrocarbon receptor nuclear translocator 2 (ARNT2) is a basic helix-loop-helix (bHLH/PAS) transcription factor involved in the development of paraventricular nucleus of the hypothalamus (PVH) through the heterodimerization with Single-minded 1 (SIM1) (Michaud et al., 2000). Using a Sendai virus-based approach, the four reprogramming factors OCT3/4, SOX2, KLF4 and C-MYC were delivered into Peripheral Blood Mononuclear Cell (PBMCs) from a 14-year-old girl with early onset obesity carrying a de novo variant (p.P130A) in ARNT2. The resulting iPSC line CUIMCi003-A had a normal karyotype, showed pluripotency and three germ layer differentiation capacity in vitro and was heterozygous for the de novo ARNT2 variant.


Assuntos
Células-Tronco Pluripotentes Induzidas , Adolescente , Translocador Nuclear Receptor Aril Hidrocarboneto , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Feminino , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Leucócitos Mononucleares/metabolismo , Obesidade/genética
11.
Toxicol Appl Pharmacol ; 426: 115639, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34256052

RESUMO

Polychlorinated biphenyls (PCBs) are endocrine disrupting chemicals with documented, though mechanistically ill-defined, reproductive toxicity. The toxicity of dioxin-like PCBs, such as PCB126, is mediated via the aryl hydrocarbon receptor (AHR) in non-ovarian tissues. The goal of this study was to examine the uterine and ovarian effects of PCB126 and test the hypothesis that the AHR is required for PCB126-induced reproductive toxicity. Female Holzman-Sprague Dawley wild type (n = 14; WT) and Ahr knock out (n = 11; AHR-/-) rats received a single intraperitoneal injection of either corn oil vehicle (5 ml/kg: WT_O and AHR-/-_O) or PCB126 (1.63 mg/kg in corn oil: WT_PCB and AHR-/-_PCB) at four weeks of age. The estrous cycle was synchronized and ovary and uterus were collected 28 days after exposure. In WT rats, PCB126 exposure reduced (P < 0.05) body and ovary weight, uterine gland number, uterine area, progesterone, 17ß-estradiol and anti-Müllerian hormone level, secondary and antral follicle and corpora lutea number but follicle stimulating hormone level increased (P < 0.05). In AHR-/- rats, PCB126 exposure increased (P ≤ 0.05) circulating luteinizing hormone level. Ovarian or uterine mRNA abundance of biotransformation, and inflammation genes were altered (P < 0.05) in WT rats due to PCB126 exposure. In AHR-/- rats, the transcriptional effects of PCB126 were restricted to reductions (P < 0.05) in three inflammatory genes. These findings support a functional role for AHR in the female reproductive tract, illustrate AHR's requirement in PCB126-induced reprotoxicity, and highlight the potential risk of dioxin-like compounds on female reproduction.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/deficiência , Disruptores Endócrinos/toxicidade , Bifenilos Policlorados/toxicidade , Receptores de Hidrocarboneto Arílico/deficiência , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Biotransformação/genética , Peso Corporal/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Hormônios/sangue , Tamanho do Órgão/efeitos dos fármacos , Ovário/efeitos dos fármacos , Ovário/metabolismo , Ovário/patologia , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Ratos Transgênicos , Receptores de Hidrocarboneto Arílico/genética , Reprodução/efeitos dos fármacos , Útero/efeitos dos fármacos , Útero/metabolismo , Útero/patologia
12.
Plant Physiol Biochem ; 166: 1087-1095, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34303268

RESUMO

Lily (Lilium spp.), with its beautiful flower, is an important horticultural crop and a popular ornamental plant, but because the abundant pollen pollutes the flowers and surroundings, its use is restricted. To solve this problem, the mechanism of pollen development in lily needs to be analyzed. However, the complex and delicate process of anther development in lily remains largely unknown. In this study, LoUDT1, a bHLH transcription factor (TF), was isolated and identified in lily. LoUDT1 was closely related to OsUDT1 of Oryza sativa and AtDYT1 of Arabidopsis. It was localized in the cytoplasm and nucleus and showed no transcriptional activation in yeast cells. LoUDT1 interacted with another bHLH TF, LoAMS, and the interaction depended on their BIF domains. LoUDT1 and LoAMS were both expressed in the anthers but showed different expression patterns. LoUDT1 was continuously expressed during the entire development of anthers, whereas LoAMS was only highly expressed early in anther development. With overexpression of LoUDT1 in Arabidopsis, normal anther development was affected and defective pollens were produced, which caused partial male sterility of transgenic plants. These defects depended on the level of LoUDT1 accumulation. By contrast, with the appropriate expression of LoUDT1 in a dyt1-3 mutant, normal pollen grains were produced, showing partial fertility. Thus, LoUDT1 might be a key regulator of anther development in lily. By further increasing the understanding of anther development, the results of this study can provide a theoretical basis for the molecular breeding of pollen-free lilies.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos , Flores/crescimento & desenvolvimento , Lilium , Proteínas de Plantas , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/fisiologia , Flores/genética , Regulação da Expressão Gênica de Plantas , Lilium/genética , Lilium/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/fisiologia
13.
BMC Ecol Evol ; 21(1): 147, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34325655

RESUMO

BACKGROUND: hes genes are chordate homologs of Drosophila genes, hairy and enhancer of split, which encode a basic helix-loop-helix (bHLH) transcriptional repressor with a WRPW motif. Various developmental functions of hes genes, including early embryogenesis and neurogenesis, have been elucidated in vertebrates. However, their orthologous relationships remain unclear partly because of less conservation of relatively short amino acid sequences, the fact that the genome was not analyzed as it is today, and species-specific genome duplication. This results in complicated gene names in vertebrates, which are not consistent in orthologs. We previously revealed that Xenopus frogs have two clusters of hes5, named "the hes5.1 cluster" and "the hes5.3 cluster", but the origin and the conservation have not yet been revealed. RESULTS: Here, we elucidated the orthologous and paralogous relationships of all hes genes of human, mouse, chicken, gecko, zebrafish, medaka, coelacanth, spotted gar, elephant shark and three species of frogs, Xenopus tropicalis (X. tropicalis), X. laevis, Nanorana parkeri, by phylogenetic and synteny analyses. Any duplicated hes5 were not found in mammals, whereas hes5 clusters in teleost were conserved although not as many genes as the three frog species. In addition, hes5 cluster-like structure was found in the elephant shark genome, but not found in cyclostomata. CONCLUSION: These data suggest that the hes5 cluster existed in the gnathostome ancestor but became a single gene in mammals. The number of hes5 cluster genes were specifically large in frogs.


Assuntos
Fatores de Transcrição , Peixe-Zebra , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Humanos , Camundongos , Filogenia , Proteínas Repressoras/genética , Sintenia , Fatores de Transcrição/genética , Peixe-Zebra/genética
14.
Int J Mol Sci ; 22(11)2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198826

RESUMO

The aryl hydrocarbon receptor (AHR) is a cytosolic receptor which is involved in diverse cellular events in humans. The most well-characterized function of AHR is its ability to upregulate gene transcription after exposure to its ligands, such as environmental toxicants, dietary antioxidants, drugs, and endogenous ligands. The cellular content of AHR is partly controlled by its degradation via the ubiquitin-proteasome system and the lysosome-dependent autophagy. We used human cervical cancer (HeLa) cells to investigate how AHR undergoes protein degradation and how its activity is modulated. Since the glycogen synthase kinase 3 beta (GSK3ß)-mediated phosphorylation can trigger protein degradation and substrates of GSK3ß contain stretches of serine/threonine residues which can be found in AHR, we examined whether degradation and activity of AHR can be controlled by GSK3ß. We observed that AHR undergoes the GSK3ß-dependent, LC3-mediated lysosomal degradation without ligand treatment. The AHR can be phosphorylated in a GSK3ß-dependent manner at three putative sites (S436/S440/S444, S689/S693/T697, and S723/S727/T731), which leads to lysosomal degradation of the AHR protein. Inhibition of the GSK3ß activity suppresses the ligand-activated transcription of an AHR target gene in HeLa, human liver cancer (Hep3B), and human breast cancer (MCF-7) cells. Collectively, our findings support that phosphorylation of AHR by GSK3ß is essential for the optimal activation of its target gene transcription and this phosphorylation may partake as an "off" switch by subjecting the receptor to lysosomal degradation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Glicogênio Sintase Quinase 3 beta/genética , Neoplasias/genética , Receptores de Hidrocarboneto Arílico/genética , Transcrição Genética , Autofagia/genética , Células HeLa , Humanos , Lisossomos/genética , Células MCF-7 , Neoplasias/patologia , Complexo de Endopeptidases do Proteassoma/genética , Proteólise , Ubiquitina/genética
15.
Nat Commun ; 12(1): 3997, 2021 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-34183666

RESUMO

Despite obesity being a predisposing factor for pancreatic ß-cell dysfunction and loss, the mechanisms underlying its negative effect on insulin-secreting cells remain poorly understood. In this study, we identify an islet-enriched long non-coding RNA (lncRNA), which we name ß-cell function and apoptosis regulator (ßFaar). ßFaar is dramatically downregulated in the islets of the obese mice, and a low level of ßFaar is necessary for the development of obesity-associated ß-cell dysfunction and apoptosis. Mechanistically, ßFaar promote the synthesis and secretion of insulin by upregulating islet-specific genes Ins2, NeuroD1, and Creb1 through sponging miR-138-5p. In addition, using quantitative mass spectrometry, we identify TRAF3IP2 and SMURF1 as interacting proteins that are specifically associated with ßFaar. We demonstrate that SMURF1 ubiquitin ligase activity is essential for TRAF3IP2 ubiquitination and activation of NF-κB-mediate ß-cell apoptosis. Our experiments provide direct evidence that dysregulated ßFaar contributes to the development of obesity-induced ß-cell injury and apoptosis.


Assuntos
Apoptose/genética , Células Secretoras de Insulina/metabolismo , Insulina/biossíntese , Obesidade/patologia , RNA Longo não Codificante/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Sobrevivência Celular/fisiologia , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Diabetes Mellitus Tipo 2/patologia , Humanos , Insulina/genética , Secreção de Insulina/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , MicroRNAs/genética , NF-kappa B/metabolismo , Obesidade/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação/fisiologia
16.
Toxicology ; 458: 152831, 2021 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-34097992

RESUMO

Aryl hydrocarbon receptor (AHR) activation via 2,3,7,8-tetrachlorodibenzofuran (TCDF) induces the accumulation of hepatic lipids. Here we report that AHR activation by TCDF (24  µg/kg body weight given orally for five days) induced significant elevation of hepatic lipids including ceramides in mice, was associated with increased expression of key ceramide biosynthetic genes, and increased activity of their respective enzymes. Results from chromatin immunoprecipitation (ChIP), electrophoretic mobility shift assay (EMSA) and cell-based reporter luciferase assays indicated that AHR directly activated the serine palmitoyltransferase long chain base subunit 2 (Sptlc2, encodes serine palmitoyltransferase 2 (SPT2)) gene whose product catalyzes the initial rate-limiting step in de novo sphingolipid biosynthesis. Hepatic ceramide accumulation was further confirmed by mass spectrometry-based lipidomics. Taken together, our results revealed that AHR activation results in the up-regulation of Sptlc2, leading to ceramide accumulation, thus promoting lipogenesis, which can induce hepatic lipid accumulation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ceramidas/biossíntese , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Receptores de Hidrocarboneto Arílico/metabolismo , Ativação Metabólica/efeitos dos fármacos , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Benzofuranos/farmacologia , Ceramidas/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lipidômica , Fígado/enzimologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Hidrocarboneto Arílico/genética , Serina C-Palmitoiltransferase/genética , Serina C-Palmitoiltransferase/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Triglicerídeos/metabolismo
17.
Plant Sci ; 309: 110952, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34134848

RESUMO

Linalool is an aromatic monoterpene produced in the Chinese medicinal plant Dendrobium officinale, but little information is available on the regulation of linalool biosynthesis. Here, a novel basic helix-loop-helix (bHLH) transcription factor, DobHLH4 from D. officinale, was identified and functionally characterized. The expression profile of DobHLH4 was positively correlated with that of DoTPS10 (R2 = 0.985, p < 0.01), which encodes linalool synthase that is responsible for linalool production, during floral development. DobHLH4 was highly expressed in petals, and was significantly induced by methyl jasmonate. Analysis of subcellular localization showed that DobHLH4 was located in the nucleus. Yeast one-hybrid and dual-luciferase assays indicated that DobHLH4 bound directly to the DoTPS10 promoter harboring the G-box element, and up-regulated DoTPS10 expression. A yeast two-hybrid screen confirmed that DobHLH4 physically interacted with DoJAZ1, suggesting that DobHLH4 might function in the jasmonic acid-mediated accumulation of linalool. Furthermore, transient overexpression of DobHLH4 in D. officinale petals significantly increased linalool production by triggering linalool biosynthetic pathway genes, especially DoTPS10. We suggest a hypothetical model that depicts how jasmonic acid signaling may regulate DoTPS10 by interacting with DobHLH4 and DoJAZ1. In doing so, the formation of linalool is controlled. Our results indicate that DobHLH4 is a positive regulator of linalool biosynthesis and may be a promising target for in vitro-based metabolic engineering to produce linalool.


Assuntos
Acetatos/metabolismo , Monoterpenos Acíclicos/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Ciclopentanos/metabolismo , Dendrobium/genética , Oxilipinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Vias Biossintéticas , Dendrobium/química , Dendrobium/metabolismo , Flores/química , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas , Óleos Voláteis/metabolismo , Óleos Vegetais/metabolismo , Proteínas de Plantas/genética
18.
Nat Commun ; 12(1): 3876, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162856

RESUMO

Testicular development and function rely on interactions between somatic cells and the germline, but similar to other organs, regenerative capacity declines in aging and disease. Whether the adult testis maintains a reserve progenitor population remains uncertain. Here, we characterize a recently identified mouse testis interstitial population expressing the transcription factor Tcf21. We found that TCF21lin cells are bipotential somatic progenitors present in fetal testis and ovary, maintain adult testis homeostasis during aging, and act as potential reserve somatic progenitors following injury. In vitro, TCF21lin cells are multipotent mesenchymal progenitors which form multiple somatic lineages including Leydig and myoid cells. Additionally, TCF21+ cells resemble resident fibroblast populations reported in other organs having roles in tissue homeostasis, fibrosis, and regeneration. Our findings reveal that the testis, like other organs, maintains multipotent mesenchymal progenitors that can be potentially leveraged in development of future therapies for hypoandrogenism and/or infertility.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Diferenciação Celular/genética , Homeostase/genética , Células-Tronco Mesenquimais/metabolismo , Regeneração/genética , Testículo/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Linhagem da Célula/genética , Células Cultivadas , Feminino , Perfilação da Expressão Gênica/métodos , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Masculino , Células-Tronco Mesenquimais/citologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise de Célula Única/métodos , Testículo/citologia
19.
Toxicol Lett ; 349: 155-164, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34171359

RESUMO

Cytochrome P450 1A1 (CYP1A1) is a member of a subfamily of enzymes involved in the metabolism of both endogenous and exogenous substrates and the chemical activation of xenobiotics to carcinogenic derivatives. Here, the effects of nicotine, a major psychoactive compound present in cigarette smoke, on CYP1A1 expression and human hepatocellular carcinoma (HepG2) cell proliferation were investigated. Nicotine stimulated CYP1A1 expression via the transcription factors, activator protein 1, nuclear factor-kappa B, and the aryl hydrocarbon receptor (AhR) signaling pathway. Pharmacological inhibition and mutagenesis studies indicated that p38 mitogen-activated protein kinase, as well as RelA (or p65), mediated the upregulation of CYP1A1 of nicotine in HepG2 cells. The antioxidant compound, N-acetyl-cysteine, abrogated nicotine-activated production of reactive oxygen species and inhibited CYP1A1 expression by nicotine. Furthermore, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase activity was inhibited by diphenyleneiodonium (an NADPH oxidase inhibitor). Thus, these results demonstrated that AhR played an important role in nicotine-induced CYP1A1 expression. Additionally, liver hepatocellular carcinoma HepG2 cells treated with nicotine exhibited markedly enhanced proliferation via CYP1A1 expression and Akt activation.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma Hepatocelular/enzimologia , Citocromo P-450 CYP1A1/biossíntese , Neoplasias Hepáticas/enzimologia , Nicotina/toxicidade , Agonistas Nicotínicos/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Fator de Transcrição AP-1/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proliferação de Células/efeitos dos fármacos , Citocromo P-450 CYP1A1/genética , Indução Enzimática , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Transdução de Sinais , Fator de Transcrição AP-1/genética , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
20.
Nat Commun ; 12(1): 3656, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-34135347

RESUMO

Plants respond to high ambient temperature by implementing a suite of morphological changes collectively termed thermomorphogenesis. Here we show that the above and below ground tissue-response to high ambient temperature are mediated by distinct transcription factors. While the central hub transcription factor, PHYTOCHROME INTERCTING FACTOR 4 (PIF4) regulates the above ground tissue response, the below ground root elongation is primarily regulated by ELONGATED HYPOCOTYL 5 (HY5). Plants respond to high temperature by largely expressing distinct sets of genes in a tissue-specific manner. HY5 promotes root thermomorphogenesis via directly controlling the expression of many genes including the auxin and BR pathway genes. Strikingly, the above and below ground thermomorphogenesis is impaired in spaQ. Because SPA1 directly phosphorylates PIF4 and HY5, SPAs might control the stability of PIF4 and HY5 to regulate thermomorphogenesis in both tissues. These data collectively suggest that plants employ distinct combination of SPA-PIF4-HY5 module to regulate tissue-specific thermomorphogenesis.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Brassinosteroides/metabolismo , Proteínas de Ciclo Celular/metabolismo , Regulação da Expressão Gênica de Plantas , Temperatura Alta , Morfogênese/genética , Fosforilação , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Plântula/genética , Plântula/crescimento & desenvolvimento
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