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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.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(9): 869-872, 2021 Sep 10.
Artigo em Chinês | MEDLINE | ID: mdl-34487533

RESUMO

OBJECTIVE: To identify the etiology of a patient with severe symptoms of DMD and to trace its pathogenic gene, so as to provide a basis for genetic counseling and clinical intervention. METHODS: Multiple ligation-dependent probe amplification (MLPA) technique was used to analyze exon deletion/repetitive variant of DMD gene, and further analysis was performed by chromosome G-banding, fluorescence in situ hybridization (FISH) and SNP array analysis. RESULTS: The MLPA results of the proband showed that the exon 1-79 of DMD gene were deleted, the G-banding karyotype of blood sample was 46, XY, and the deletion of the short arm of X chromosome was found by FISH. SNP array results showed that 5.8Mb (29 628 158-35 434 714) deletion occurred in the Xp21.2p21.1 region of X chromosome, and the patient was diagnosed as the contiguous deletion syndrome involving the genes of IL1RAPL, MAGEB1-4, ROB, CXorf2, GM, AP3K7IP, FTHL1, DMD, FAM47A, TMEM47, and FAM47B. CONCLUSION: The exact pathogenic site of this family is the deletion of 5.8 Mb (29 628 158-35 434 714) in the Xp21.2p21.1 region of X chromosome, which can be used for prenatal diagnosis. High resolution SNP array technique plays an important role in detecting potential chromosome abnormalities in patients.


Assuntos
Distrofia Muscular de Duchenne , Distrofina/genética , Éxons , Feminino , Deleção de Genes , Humanos , Hibridização in Situ Fluorescente , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/genética , Gravidez , Diagnóstico Pré-Natal
3.
Int J Mol Sci ; 22(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34445433

RESUMO

The cornea is an anterior eye structure specialized for vision. The corneal endothelium and stroma are derived from the periocular mesenchyme (POM), which originates from neural crest cells (NCCs), while the stratified corneal epithelium develops from the surface ectoderm. Activating protein-2ß (AP-2ß) is highly expressed in the POM and important for anterior segment development. Using a mouse model in which AP-2ß is conditionally deleted in the NCCs (AP-2ß NCC KO), we investigated resulting corneal epithelial abnormalities. Through PAS and IHC staining, we observed structural and phenotypic changes to the epithelium associated with AP-2ß deletion. In addition to failure of the mutant epithelium to stratify, we also observed that Keratin-12, a marker of the differentiated epithelium, was absent, and Keratin-15, a limbal and conjunctival marker, was expanded across the central epithelium. Transcription factors PAX6 and P63 were not observed to be differentially expressed between WT and mutant. However, growth factor BMP4 was suppressed in the mutant epithelium. Given the non-NCC origin of the epithelium, we hypothesize that the abnormalities in the AP-2ß NCC KO mouse result from changes to regulatory signaling from the POM-derived stroma. Our findings suggest that stromal pathways such as Wnt/ß-Catenin signaling may regulate BMP4 expression, which influences cell fate and stratification.


Assuntos
Proteína Morfogenética Óssea 4/metabolismo , Regulação para Baixo , Epitélio Corneano/anormalidades , Deleção de Genes , Fator de Transcrição AP-2/genética , Animais , Proteína Morfogenética Óssea 4/genética , Diferenciação Celular , Epitélio Corneano/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Inativação de Genes , Queratina-12/metabolismo , Queratina-15/metabolismo , Masculino , Camundongos , Crista Neural/metabolismo , Fenótipo , Fator de Transcrição AP-2/metabolismo , Via de Sinalização Wnt
4.
Nucleic Acids Res ; 49(15): 8535-8555, 2021 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-34358317

RESUMO

Gene deletion and gene expression alteration can lead to growth defects that are amplified or reduced when a second mutation is present in the same cells. We performed 154 genetic interaction mapping (GIM) screens with query mutants related with RNA metabolism and estimated the growth rates of about 700 000 double mutant Saccharomyces cerevisiae strains. The tested targets included the gene deletion collection and 900 strains in which essential genes were affected by mRNA destabilization (DAmP). To analyze the results, we developed RECAP, a strategy that validates genetic interaction profiles by comparison with gene co-citation frequency, and identified links between 1471 genes and 117 biological processes. In addition to these large-scale results, we validated both enhancement and suppression of slow growth measured for specific RNA-related pathways. Thus, negative genetic interactions identified a role for the OCA inositol polyphosphate hydrolase complex in mRNA translation initiation. By analysis of suppressors, we found that Puf4, a Pumilio family RNA binding protein, inhibits ribosomal protein Rpl9 function, by acting on a conserved UGUAcauUA motif located downstream the stop codon of the RPL9B mRNA. Altogether, the results and their analysis should represent a useful resource for discovery of gene function in yeast.


Assuntos
Genes Fúngicos , RNA Fúngico/metabolismo , Saccharomyces cerevisiae/genética , Alelos , Deleção de Genes , Pleiotropia Genética , Fosfatos de Inositol/metabolismo , Iniciação Traducional da Cadeia Peptídica , Estabilidade de RNA , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/fisiologia , Proteínas Ribossômicas/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/fisiologia
5.
FASEB J ; 35(9): e21859, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34418172

RESUMO

Cyclic nucleotide-gated (CNG) channels are important mediators in the transduction pathways of rod and cone photoreceptors. Native CNG channels are heterotetramers composed of homologous A and B subunits. Biallelic mutations in CNGA1 or CNGB1 genes result in autosomal recessive retinitis pigmentosa (RP). To investigate the pathogenic mechanism of CNG channel-associated retinal degeneration, we developed a mouse model of CNGA1 knock-out using CRISPR/Cas9 technology. We observed progressive retinal thinning and a concomitant functional deficit in vivo as typical phenotypes for RP. Immunofluorescence and TUNEL staining showed progressive degeneration in rods and cones. Moreover, microglial activation and oxidative stress damage occurred in parallel. RNA-sequencing analysis of the retinae suggested down-regulated synaptic transmission and phototransduction as early as 9 days postnatal, possibly inducing later photoreceptor degeneration. In addition, the down-regulated PI3K-AKT-mTOR pathway indicated upregulation of autophagic process, and chaperone-mediated autophagy was further shown to coincide with the time course of photoreceptor death. Taken together, our studies add to a growing body of research exploring the mechanisms of photoreceptor death during RP progression and provide a novel CNGA1 knockout mouse model for potential development of therapies.


Assuntos
Canais de Cátion Regulados por Nucleotídeos Cíclicos/deficiência , Canais de Cátion Regulados por Nucleotídeos Cíclicos/genética , Deleção de Genes , Degeneração Retiniana/genética , Animais , Caspases , Autofagia Mediada por Chaperonas , Feminino , Luz , Camundongos , Camundongos Knockout , Microglia , Neuroglia , Estresse Oxidativo/efeitos da radiação , Fenótipo , Células Fotorreceptoras de Vertebrados/metabolismo , Células Fotorreceptoras de Vertebrados/patologia , RNA-Seq , Degeneração Retiniana/patologia , Epitélio Pigmentado da Retina , Transcriptoma
6.
Int J Mol Sci ; 22(16)2021 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-34445401

RESUMO

Class I phosphoinositide 3-kinases (PI3K) are involved in the development of normal and autoimmune responses, including Experimental Autoimmune Encephalomyelitis (EAE), a mouse model for human multiple sclerosis (MS). Here, the role of the ubiquitously expressed class IA PI3K p110α catalytic subunits in EAE has been analyzed using a model of Cre/flox mediated T cell specific deletion of p110α catalytic chain (p110αΔT). Comparison of two month-old (young) and six month-old (mature) p110αΔT mice and their wild type (WT) counterparts indicated loss of spleen CD4+ T cells that increased with age, indicating a role of p110α in their homeostasis. In contrast, CD4+ T regulatory (Treg) cells were enhanced in mature p110αΔT mice when compared to WT mice. Since Myelin Oligodendrocyte Glycoprotein (MOG) peptide-induced EAE is dependent on, or mediated by CD4+ T cells and CD4+ T cell-derived cytokines and controlled by Treg cells, development of EAE in young and mature WT or p110αΔT mice was analyzed. EAE clinical symptoms and disease scores in six month p110αΔT mice were significantly lower than those of mature WT, or young WT and p110αΔT mice. Furthermore, ex vivo antigen activation of lymph node cells from MOG immunized mature p110αΔT mice induced significantly lower levels of IFN-γ and IL-17A than young p110αΔT or young and mature WT mice. Other cytokines including IL-2, IL-10 or TNF-α showed no significant differences between p110αΔT and WT mature mice. Our data show a lower incidence of MOG-induced EAE in mature p110αΔT mice linked to altered T cell homeostasis and lower secretion of inflammatory cytokines.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/genética , Encefalomielite Autoimune Experimental/imunologia , Deleção de Genes , Animais , Encefalomielite Autoimune Experimental/genética , Homeostase , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/metabolismo
7.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360709

RESUMO

Toxoplasma gondii (T. gondii) is an important human and veterinary pathogen causing life-threatening disease in immunocompromised patients. The UBL-UBA shuttle protein family are important components of the ubiquitin-proteasome system. Here, we identified a novel UBL-UBA shuttle protein DSK2b that is charactered by an N-terminal ubiquitin-like domain (UBL) and a C-terminal ubiquitin-associated domain (UBA). DSK2b was localized in the cytoplasm and nucleus. The deletion of dsk2b did not affect the degradation of ubiquitinated proteins, parasite growth in vitro or virulence in mice. The double-gene knockout of dsk2b and its paralogs dsk2a (ΔΔdsk2adsk2b) results in a significant accumulation of ubiquitinated proteins and the asynchronous division of T. gondii. The growth of ΔΔdsk2adsk2b was significantly inhibited in vitro, while virulence in mice was not attenuated. In addition, autophagy occurred in the ΔΔdsk2adsk2b, which was speculated to degrade the accumulated ubiquitinated proteins in the parasites. Overall, DSK2b is a novel UBL-UBA shuttle protein contributing to the degradation of ubiquitinated proteins and is important for the synchronous cell division of T. gondii.


Assuntos
Divisão Celular , Proteólise , Proteínas de Protozoários/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Toxoplasma/metabolismo , Ubiquitinação , Animais , Deleção de Genes , Humanos , Camundongos , Proteínas de Protozoários/genética , Receptores Citoplasmáticos e Nucleares/genética , Toxoplasma/genética , Toxoplasma/patogenicidade
8.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360727

RESUMO

Hereditary leiomyomatosis and renal cell carcinoma (HL (RCC)) entails cutaneous and uterine leiomyomatosis with aggressive type 2 papillary RCC-like histology. HLRCC is caused by pathogenic variants in the FH gene, which encodes fumarate hydratase (FH). Here, we describe an episode of young-onset RCC caused by a genomic FH deletion that was diagnosed via clinical sequencing. A 35-year-old woman was diagnosed with RCC and multiple metastases: histopathological analyses supported a diagnosis of FH-deficient RCC. Although the patient had neither skin tumors nor a family history of HLRCC, an aggressive clinical course at her age and pathological diagnosis of FH-deficient RCC suggested a germline FH variant. After counseling, the patient provided written informed consent for germline genetic testing. She was simultaneously subjected to paired tumor profiling tests targeting the exome to identify a therapeutic target. Although conventional germline sequencing did not detect FH variants, exome sequencing revealed a heterozygous germline FH deletion. As such, paired tumor profiling, not conventional sequencing, was required to identify this genetic deletion. RCC caused by a germline FH deletion has hitherto not been described in Japan, and the FH deletion detected in this patient was presumed to be of maternal European origin. Although the genotype-phenotype correlation in HLRCC-related tumors is unclear, the patient's family was advised to undergo genetic counseling to consider additional RCC screening.


Assuntos
Fumarato Hidratase/deficiência , Deleção de Genes , Mutação em Linhagem Germinativa , Leiomiomatose/genética , Erros Inatos do Metabolismo/genética , Hipotonia Muscular/genética , Síndromes Neoplásicas Hereditárias/genética , Transtornos Psicomotores/genética , Neoplasias Cutâneas/genética , Neoplasias Uterinas/genética , Adulto , Feminino , Fumarato Hidratase/genética , Testes Genéticos , Humanos
9.
J Agric Food Chem ; 69(33): 9625-9631, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34382797

RESUMO

Cofactor availability is often a rate-limiting factor in the bioconversion of xylose to xylitol. The overexpression of pentose phosphate pathway genes and the deletion of Embden-Meyerhof-Parnas pathway genes can modulate the glucose metabolic flux and increase the intracellular NADPH supply, enabling Escherichia coli cells to produce xylitol from corncob hydrolysates. The effects of zwf and/or gnd overexpression and pfkA, pfkB, and/or pgi deletion on the intracellular redox environment and xylitol production were examined. The NADPH-enhanced strain 2bpgi produced 162 g/L xylitol from corncob hydrolysates after a 76 h fed-batch fermentation in a 15 L bioreactor, which was 13.3% greater than the 143 g/L xylitol produced by the IS5-d control strain. Additionally, the xylitol productivity and xylitol yield per glucose for 2bpgi were 2.13 g/L/h and 2.50 g/g, respectively. Thus, the genetic modifications in 2bpgi significantly enhanced NADPH regeneration, making 2bpgi a potentially useful strain for the industrial-scale production of xylitol from detoxified corncob hydrolysates.


Assuntos
Via de Pentose Fosfato , Xilitol , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Deleção de Genes , Glucose , Glicólise , NADP/metabolismo , Fosfatos , Xilose
10.
Nat Commun ; 12(1): 5013, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-34408147

RESUMO

Human families with chromosomal rearrangements at 2q31, where the human HOXD locus maps, display mesomelic dysplasia, a severe shortening and bending of the limb. In mice, the dominant Ulnaless inversion of the HoxD cluster produces a similar phenotype suggesting the same origin for these malformations in humans and mice. Here we engineer 1 Mb inversion including the HoxD gene cluster, which positioned Hoxd13 close to proximal limb enhancers. Using this model, we show that these enhancers contact and activate Hoxd13 in proximal cells, inducing the formation of mesomelic dysplasia. We show that a secondary Hoxd13 null mutation in-cis with the inversion completely rescues the alterations, demonstrating that ectopic HOXD13 is directly responsible for this bone anomaly. Single-cell expression analysis and evaluation of HOXD13 binding sites suggests that the phenotype arises primarily by acting through genes normally controlled by HOXD13 in distal limb cells. Altogether, these results provide a conceptual and mechanistic framework to understand and unify the molecular origins of human mesomelic dysplasia associated with 2q31.


Assuntos
Anormalidades Múltiplas/genética , Doenças do Desenvolvimento Ósseo/genética , Proteínas de Homeodomínio/genética , Deformidades Congênitas dos Membros/genética , Fatores de Transcrição/genética , Anormalidades Múltiplas/embriologia , Anormalidades Múltiplas/metabolismo , Animais , Doenças do Desenvolvimento Ósseo/embriologia , Doenças do Desenvolvimento Ósseo/metabolismo , Modelos Animais de Doenças , Feminino , Deleção de Genes , Proteínas de Homeodomínio/metabolismo , Humanos , Deformidades Congênitas dos Membros/embriologia , Deformidades Congênitas dos Membros/metabolismo , Mutação com Perda de Função , Masculino , Camundongos Endogâmicos C57BL , Família Multigênica , Fatores de Transcrição/metabolismo
11.
Int J Mol Sci ; 22(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34360582

RESUMO

Although considered a rare retinal dystrophy, retinitis pigmentosa (RP) is the primary cause of hereditary blindness. Given its diverse genetic etiology (>3000 mutations in >60 genes), there is an urgent need for novel treatments that target common features of the disease. TLR2 is a key activator of innate immune response. To examine its role in RP progression we characterized the expression profile of Tlr2 and its adaptor molecules and the consequences of Tlr2 deletion in two genetically distinct models of RP: Pde6brd10/rd10 (rd10) and RhoP23H/+ (P23H/+) mice. In both models, expression levels of Tlr2 and its adaptor molecules increased in parallel with those of the proinflammatory cytokine Il1b. In rd10 mice, deletion of a single Tlr2 allele had no effect on visual function, as evaluated by electroretinography. However, in both RP models, complete elimination of Tlr2 attenuated the loss of visual function and mitigated the loss of photoreceptor cell numbers. In Tlr2 null rd10 mice, we observed decreases in the total number of microglial cells, assessed by flow cytometry, and in the number of microglia infiltrating the photoreceptor layers. Together, these results point to TLR2 as a mutation-independent therapeutic target for RP.


Assuntos
Modelos Animais de Doenças , Deleção de Genes , Microglia/metabolismo , Fármacos Neuroprotetores , Degeneração Retiniana/prevenção & controle , Retinite Pigmentosa/complicações , Receptor 2 Toll-Like/fisiologia , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/citologia , Degeneração Retiniana/etiologia , Degeneração Retiniana/metabolismo , Degeneração Retiniana/patologia
12.
Int J Mol Sci ; 22(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34360594

RESUMO

Glucocorticoids provide indispensable anti-inflammatory therapies. However, metabolic adverse effects including muscle wasting restrict their use. The enzyme 11beta-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) modulates peripheral glucocorticoid responses through pre-receptor metabolism. This study investigates how 11ß-HSD1 influences skeletal muscle responses to glucocorticoid therapy for chronic inflammation. We assessed human skeletal muscle biopsies from patients with rheumatoid arthritis and osteoarthritis for 11ß-HSD1 activity ex vivo. Using the TNF-α-transgenic mouse model (TNF-tg) of chronic inflammation, we examined the effects of corticosterone treatment and 11ß-HSD1 global knock-out (11ßKO) on skeletal muscle, measuring anti-inflammatory gene expression, muscle weights, fiber size distribution, and catabolic pathways. Muscle 11ß-HSD1 activity was elevated in patients with rheumatoid arthritis and correlated with inflammation markers. In murine skeletal muscle, glucocorticoid administration suppressed IL6 expression in TNF-tg mice but not in TNF-tg11ßKO mice. TNF-tg mice exhibited reductions in muscle weight and fiber size with glucocorticoid therapy. In contrast, TNF-tg11ßKO mice were protected against glucocorticoid-induced muscle atrophy. Glucocorticoid-mediated activation of catabolic mediators (FoxO1, Trim63) was also diminished in TNF-tg11ßKO compared to TNF-tg mice. In summary, 11ß-HSD1 knock-out prevents muscle atrophy associated with glucocorticoid therapy in a model of chronic inflammation. Targeting 11ß-HSD1 may offer a strategy to refine the safety of glucocorticoids.


Assuntos
11-beta-Hidroxiesteroide Desidrogenase Tipo 1/genética , Artrite Reumatoide/tratamento farmacológico , Deleção de Genes , Glucocorticoides/efeitos adversos , Atrofia Muscular/prevenção & controle , Osteoartrite do Quadril/tratamento farmacológico , Animais , Artrite Reumatoide/patologia , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/genética , Atrofia Muscular/patologia , Osteoartrite do Quadril/patologia
13.
FASEB J ; 35(8): e21826, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34320244

RESUMO

In pancreatic cancer, autocrine insulin-like growth factor-1 (IGF-1) and paracrine insulin stimulate both IGF-1 receptor (IGF1R) and insulin receptor (IR) to increase tumor growth and glycolysis. In pancreatic cancer patients, cancer-induced glycolysis increases hepatic gluconeogenesis, skeletal muscle proteolysis, and fat lipolysis and, thereby, causes cancer cachexia. As a protein coexisting with IGF1R and IR, caveolin-1 (cav-1) may be involved in pancreatic cancer-induced cachexia. We undertook the present study to test this hypothesis. Out of wild-type MiaPaCa2 and AsPC1 human pancreatic cancer cell lines, we created their stable sub-lines whose cav-1 expression was diminished with RNA interference or increased with transgene expression. When these cells were studied in vitro, we found that cav-1 regulated IGF1R/IR expression and activation and also regulated cellular glycolysis. We transplanted the different types of MiaPaCa2 cells in growing athymic mice for 8 weeks, using intact athymic mice as tumor-free controls. We found that cav-1 levels in tumor grafts were correlated with expression levels of the enzymes that regulated hepatic gluconeogenesis, skeletal muscle proteolysis, and fat lipolysis in the respective tissues. When the tumors had original or increased cav-1, their carriers' body weight gain was less than the tumor-free reference. When cav-1 was diminished in tumors, the tumor carriers' body weight gain was not changed significantly, compared to the tumor-free reference. In conclusion, cav-1 in pancreatic cancer cells stimulated IGF1R/IR and glycolysis in the cancer cells and triggered cachectic states in the tumor carrier.


Assuntos
Caquexia/etiologia , Caveolina 1/metabolismo , Glicólise/fisiologia , Neoplasias Pancreáticas/metabolismo , Receptor IGF Tipo 1/metabolismo , Receptor de Insulina/metabolismo , Animais , Caveolina 1/genética , Linhagem Celular Tumoral , Deleção de Genes , Regulação da Expressão Gênica/fisiologia , Humanos , Camundongos , Camundongos Nus , Neoplasias Experimentais/metabolismo , Receptor IGF Tipo 1/genética , Receptor de Insulina/genética
14.
Nucleic Acids Res ; 49(13): 7537-7553, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34197600

RESUMO

The synaptonemal complex (SC) is a proteinaceous structure that mediates homolog engagement and genetic recombination during meiosis. In budding yeast, Zip-Mer-Msh (ZMM) proteins promote crossover (CO) formation and initiate SC formation. During SC elongation, the SUMOylated SC component Ecm11 and the Ecm11-interacting protein Gmc2 facilitate the polymerization of Zip1, an SC central region component. Through physical recombination, cytological, and genetic analyses, we found that ecm11 and gmc2 mutants exhibit chromosome-specific defects in meiotic recombination. CO frequencies on a short chromosome (chromosome III) were reduced, whereas CO and non-crossover frequencies on a long chromosome (chromosome VII) were elevated. Further, in ecm11 and gmc2 mutants, more double-strand breaks (DSBs) were formed on a long chromosome during late prophase I, implying that the Ecm11-Gmc2 (EG) complex is involved in the homeostatic regulation of DSB formation. The EG complex may participate in joint molecule (JM) processing and/or double-Holliday junction resolution for ZMM-dependent CO-designated recombination. Absence of the EG complex ameliorated the JM-processing defect in zmm mutants, suggesting a role for the EG complex in suppressing ZMM-independent recombination. Our results suggest that the SC central region functions as a compartment for sequestering recombination-associated proteins to regulate meiosis specificity during recombination.


Assuntos
Proteínas de Ciclo Celular/genética , Troca Genética , Quebras de DNA de Cadeia Dupla , Meiose/genética , Proteínas de Saccharomyces cerevisiae/genética , Complexo Sinaptonêmico/metabolismo , Cromossomos Fúngicos , Replicação do DNA , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Retroalimentação Fisiológica , Deleção de Genes , Recombinação Genética , Saccharomyces cerevisiae/genética , Temperatura , Fatores de Transcrição/genética , Ubiquitina-Proteína Ligases/genética
15.
Nucleic Acids Res ; 49(13): 7318-7329, 2021 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-34197604

RESUMO

Integrating omics data with quantification of biological traits provides unparalleled opportunities for discovery of genetic regulators by in silico inference. However, current approaches to analyze genetic-perturbation screens are limited by their reliance on annotation libraries for prioritization of hits and subsequent targeted experimentation. Here, we present iTARGEX (identification of Trait-Associated Regulatory Genes via mixture regression using EXpectation maximization), an association framework with no requirement of a priori knowledge of gene function. After creating this tool, we used it to test associations between gene expression profiles and two biological traits in single-gene deletion budding yeast mutants, including transcription homeostasis during S phase and global protein turnover. For each trait, we discovered novel regulators without prior functional annotations. The functional effects of the novel candidates were then validated experimentally, providing solid evidence for their roles in the respective traits. Hence, we conclude that iTARGEX can reliably identify novel factors involved in given biological traits. As such, it is capable of converting genome-wide observations into causal gene function predictions. Further application of iTARGEX in other contexts is expected to facilitate the discovery of new regulators and provide observations for novel mechanistic hypotheses regarding different biological traits and phenotypes.


Assuntos
Perfilação da Expressão Gênica , Genes Reguladores , Proteólise , Fase S/genética , Software , Transcrição Genética , Proteínas de Transporte/genética , Biologia Computacional/métodos , Replicação do DNA , Deleção de Genes , Homeostase , Mutação , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
16.
Blood ; 138(3): 221-233, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34292326

RESUMO

The Chd8 gene encodes a member of the chromodomain helicase DNA-binding (CHD) family of SNF2H-like adenosine triphosphate (ATP)-dependent chromatin remodeler, the mutations of which define a subtype of autism spectrum disorders. Increasing evidence from recent studies indicates that ATP-dependent chromatin-remodeling genes are involved in the control of crucial gene-expression programs in hematopoietic stem/progenitor cell (HSPC) regulation. In this study, we identified CHD8 as a specific and essential regulator of normal hematopoiesis. Loss of Chd8 leads to severe anemia, pancytopenia, bone marrow failure, and engraftment failure related to a drastic depletion of HSPCs. CHD8 forms a complex with ATM and its deficiency increases chromatin accessibility and drives genomic instability in HSPCs causing an activation of ATM kinase that further stabilizes P53 protein by phosphorylation and leads to increased HSPC apoptosis. Deletion of P53 rescues the apoptotic defects of HSPCs and restores overall hematopoiesis in Chd8-/- mice. Our findings demonstrate that chromatin organization by CHD8 is uniquely necessary for the maintenance of hematopoiesis by integrating the ATM-P53-mediated survival of HSPCs.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Hematopoese , Células-Tronco Hematopoéticas/citologia , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Sobrevivência Celular , Células Cultivadas , Proteínas de Ligação a DNA/genética , Deleção de Genes , Células-Tronco Hematopoéticas/metabolismo , Camundongos , Pancitopenia/genética , Pancitopenia/metabolismo , Estabilidade Proteica
17.
Nat Commun ; 12(1): 4359, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34272378

RESUMO

Histone H3 lysine 9 (H3K9) methylation is a central epigenetic modification that defines heterochromatin from unicellular to multicellular organisms. In mammalian cells, H3K9 methylation can be catalyzed by at least six distinct SET domain enzymes: Suv39h1/Suv39h2, Eset1/Eset2 and G9a/Glp. We used mouse embryonic fibroblasts (MEFs) with a conditional mutation for Eset1 and introduced progressive deletions for the other SET domain genes by CRISPR/Cas9 technology. Compound mutant MEFs for all six SET domain lysine methyltransferase (KMT) genes lack all H3K9 methylation states, derepress nearly all families of repeat elements and display genomic instabilities. Strikingly, the 6KO H3K9 KMT MEF cells no longer maintain heterochromatin organization and have lost electron-dense heterochromatin. This is a compelling analysis of H3K9 methylation-deficient mammalian chromatin and reveals a definitive function for H3K9 methylation in protecting heterochromatin organization and genome integrity.


Assuntos
Fibroblastos/metabolismo , Heterocromatina/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Animais , Sistemas CRISPR-Cas , Sequenciamento de Cromatina por Imunoprecipitação , Cromatografia Líquida , Desmetilação , Epigênese Genética , Fibroblastos/enzimologia , Deleção de Genes , Heterocromatina/enzimologia , Heterocromatina/genética , Heterocromatina/ultraestrutura , Histona-Lisina N-Metiltransferase/genética , Hibridização in Situ Fluorescente , Espectrometria de Massas , Metilação , Camundongos , Microscopia Eletrônica de Transmissão , Mutação , Processamento de Proteína Pós-Traducional/genética , RNA-Seq , Sequências Repetitivas de Ácido Nucleico/genética , Retroelementos/genética , Transdução de Sinais/genética
18.
Nat Commun ; 12(1): 4344, 2021 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-34272393

RESUMO

Poised enhancers (PEs) represent a genetically distinct set of distal regulatory elements that control the expression of major developmental genes. Before becoming activated in differentiating cells, PEs are already bookmarked in pluripotent cells with unique chromatin and topological features that could contribute to their privileged regulatory properties. However, since PEs were originally characterized in embryonic stem cells (ESC), it is currently unknown whether PEs are functionally conserved in vivo. Here, we show that the chromatin and 3D structural features of PEs are conserved among mouse pluripotent cells both in vitro and in vivo. We also uncovered that the interactions between PEs and their target genes are globally controlled by the combined action of Polycomb, Trithorax and architectural proteins. Moreover, distal regulatory sequences located close to developmental genes and displaying the typical genetic (i.e. CpG islands) and chromatin (i.e. high accessibility and H3K27me3 levels) features of PEs are commonly found across vertebrates. These putative PEs show high sequence conservation within specific vertebrate clades, with only a few being evolutionary conserved across all vertebrates. Lastly, by genetically disrupting PEs in mouse and chicken embryos, we demonstrate that these regulatory elements play essential roles during the induction of major developmental genes in vivo.


Assuntos
Cromatina/metabolismo , Células-Tronco Embrionárias/metabolismo , Elementos Facilitadores Genéticos , Regulação da Expressão Gênica no Desenvolvimento/genética , Histonas/metabolismo , Fatores de Transcrição/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/genética , Linhagem Celular , Embrião de Galinha , Cromatina/genética , Sequenciamento de Cromatina por Imunoprecipitação , Ilhas de CpG , Células-Tronco Embrionárias/efeitos dos fármacos , Epigênese Genética , Deleção de Genes , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Camadas Germinativas/metabolismo , Homozigoto , Camundongos , Filogenia , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Fatores de Transcrição/genética
19.
Methods Mol Biol ; 2314: 301-321, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34235660

RESUMO

Phage recombination systems have been instrumental in the development of gene modification technologies for bacterial pathogens. In particular, the Che9 phage RecET system has been used successfully for over 10 years for making gene knockouts and fusions in Mycobacterium tuberculosis. This "recombineering" technology typically uses linear dsDNA substrates that contain a drug-resistance marker flanked by (up to) 500 base pairs of DNA homologous to the target site. Less often employed in mycobacterial recombineering is the use of oligonucleotides, which require only the action of the RecT annealase to align oligos to ssDNA regions of the replication fork, for subsequent incorporation into the chromosome. Despite the higher frequency of such events relative to dsDNA-promoted recombineering, oligo-mediated changes generally suffer from the disadvantage of not being selectable, thus making them harder to isolate. This chapter discusses steps and methodologies that increase the frequencies of finding oligo-mediated events, including the transfer of single nucleotide polymorphisms (SNPs) to mycobacterial chromosomes, and the use of oligos in conjunction with the mycobacterial phage Bxb1 site-specific recombination system for the easy generation of knockouts, insertion, and fusions, in a protocol known as ORBIT.


Assuntos
Deleção de Genes , Fusão Gênica , Mutagênese Insercional , Mycobacterium tuberculosis/genética , Oligonucleotídeos/genética , Polimorfismo de Nucleotídeo Único , Recombinação Genética , Cromossomos Bacterianos , Edição de Genes , Engenharia Genética , Genoma Bacteriano
20.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281173

RESUMO

Epoxides and diols of polyunsaturated fatty acids (PUFAs) are bioactive and can influence processes such as tumor cell proliferation and angiogenesis. Studies with inhibitors of the soluble epoxide hydrolase (sEH) in animals overexpressing cytochrome P450 enzymes or following the systemic administration of specific epoxides revealed a markedly increased incidence of tumor metastases. To determine whether PUFA epoxides increased metastases in a model of spontaneous breast cancer, sEH-/- mice were crossed onto the polyoma middle T oncogene (PyMT) background. We found that the deletion of the sEH accelerated the growth of primary tumors and increased both the tumor macrophage count and angiogenesis. There were small differences in the epoxide/diol content of tumors, particularly in epoxyoctadecamonoenic acid versus dihydroxyoctadecenoic acid, and marked changes in the expression of proteins linked with cell proliferation and metabolism. However, there was no consequence of sEH inhibition on the formation of metastases in the lymph node or lung. Taken together, our results confirm previous reports of increased tumor growth in animals lacking sEH but fail to substantiate reports of enhanced lymph node or pulmonary metastases.


Assuntos
Neoplasias da Mama/metabolismo , Epóxido Hidrolases/metabolismo , Animais , Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinogênese , Proliferação de Células/fisiologia , Transformação Celular Neoplásica , Sistema Enzimático do Citocromo P-450/metabolismo , Modelos Animais de Doenças , Epóxido Hidrolases/genética , Compostos de Epóxi/metabolismo , Ácidos Graxos Insaturados/metabolismo , Feminino , Deleção de Genes , Camundongos , Camundongos Knockout , Metástase Neoplásica , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo
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