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1.
Sensors (Basel) ; 23(17)2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37688091

RESUMO

Although measuring worker productivity is crucial, the measurement of the productivity of each worker is challenging due to their dispersion across various construction jobsites. This paper presents a framework for measuring productivity based on an inertial measurement unit (IMU) and activity classification. Two deep learning algorithms and three sensor combinations were utilized to identify and analyze the feasibility of the framework in masonry work. Using the proposed method, worker activity classification could be performed with a maximum accuracy of 96.70% using the convolutional neural network model with multiple sensors, and a minimum accuracy of 72.11% using the long short-term memory (LSTM) model with a single sensor. Productivity could be measured with an accuracy of up to 96.47%. The main contributions of this study are the proposal of a method for classifying detailed activities and an exploration of the effect of the number of IMU sensors used in measuring worker productivity.

2.
Hum Mutat ; 41(12): 2105-2118, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32906187

RESUMO

Holoprosencephaly (HPE) is the most common congenital anomaly affecting the forebrain and face in humans and occurs as frequently as 1:250 conceptions or 1:10,000 livebirths. Sonic Hedgehog signaling molecule is one of the best characterized HPE genes that plays crucial roles in numerous developmental processes including midline neural patterning and craniofacial development. The Frizzled class G-protein coupled receptor Smoothened (SMO), whose signaling activity is tightly regulated, is the sole obligate transducer of Hedgehog-related signals. However, except for previous reports of somatic oncogenic driver mutations in human cancers (or mosaic tumors in rare syndromes), any potential disease-related role of SMO genetic variation in humans is largely unknown. To our knowledge, ours is the first report of a human hypomorphic variant revealed by functional testing of seven distinct nonsynonymous SMO variants derived from HPE molecular and clinical data. Here we describe several zebrafish bioassays developed and guided by a systems biology analysis. This analysis strategy, and detection of hypomorphic variation in human SMO, demonstrates the necessity of integrating the genomic variant findings in HPE probands with other components of the Hedgehog gene regulatory network in overall medical interpretations.


Assuntos
Holoprosencefalia/genética , Holoprosencefalia/patologia , Mutação/genética , Receptor Smoothened/química , Receptor Smoothened/genética , Sequência de Aminoácidos , Animais , Mutação com Ganho de Função/genética , Regulação da Expressão Gênica no Desenvolvimento , Redes Reguladoras de Genes , Humanos , Mutação com Perda de Função/genética , Modelos Biológicos , Morfolinos/farmacologia , Mutagênese/genética , Fenótipo , Domínios Proteicos , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
3.
Hum Mutat ; 41(12): 2155-2166, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32939873

RESUMO

Genetic variation in the highly conserved Sonic Hedgehog (SHH) gene is one of the most common genetic causes for the malformations of the brain and face in humans described as the holoprosencephaly clinical spectrum. However, only a minor fraction of known SHH variants have been experimentally proven to lead to abnormal function. Employing a phenotypic rescue assay with synthetic human messenger RNA variant constructs in shha-/- knockout zebrafish, we evaluated 104 clinically reported in-frame and missense SHH variants. Our data helped us to classify them into loss of function variants (31), hypomorphic variants (33), and nonpathogenic variants (40). We discuss the strengths and weaknesses of currently accepted predictors of variant deleteriousness and the American College of Medical Genetics and Genomics guidelines for variant interpretation in the context of this functional model; furthermore, we demonstrate the robustness of model systems such as zebrafish as a rapid method to resolve variants of uncertain significance.


Assuntos
Sistemas CRISPR-Cas/genética , Variação Genética , Proteínas Hedgehog/genética , Holoprosencefalia/genética , Proteínas de Peixe-Zebra/genética , Peixe-Zebra/genética , Alelos , Animais , Modelos Animais de Doenças , Família , Estudos de Associação Genética , Guias como Assunto , Humanos , Mutação com Perda de Função/genética , Mutação/genética , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sociedades Científicas
4.
Am J Med Genet A ; 179(10): 2075-2082, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31361404

RESUMO

Zinc finger protein 462 (ZNF462) is a relatively newly discovered vertebrate specific protein with known critical roles in embryonic development in animal models. Two case reports and a case series study have described the phenotype of 10 individuals with ZNF462 loss of function variants. Herein, we present 14 new individuals with loss of function variants to the previous studies to delineate the syndrome of loss of function in ZNF462. Collectively, these 24 individuals present with recurring phenotypes that define a multiple congenital anomaly syndrome. Most have some form of developmental delay (79%) and a minority has autism spectrum disorder (33%). Characteristic facial features include ptosis (83%), down slanting palpebral fissures (58%), exaggerated Cupid's bow/wide philtrum (54%), and arched eyebrows (50%). Metopic ridging or craniosynostosis was found in a third of study participants and feeding problems in half. Other phenotype characteristics include dysgenesis of the corpus callosum in 25% of individuals, hypotonia in half, and structural heart defects in 21%. Using facial analysis technology, a computer algorithm applying deep learning was able to accurately differentiate individuals with ZNF462 loss of function variants from individuals with Noonan syndrome and healthy controls. In summary, we describe a multiple congenital anomaly syndrome associated with haploinsufficiency of ZNF462 that has distinct clinical characteristics and facial features.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas do Tecido Nervoso/genética , Fatores de Transcrição/genética , Adolescente , Adulto , Criança , Pré-Escolar , Fácies , Feminino , Humanos , Lactente , Masculino , Fenótipo , Síndrome
5.
Am J Hum Genet ; 104(5): 990-993, 2019 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-31006510

RESUMO

Holoprosencephaly is the incomplete separation of the forebrain during embryogenesis. Both genetic and environmental etiologies have been determined for holoprosencephaly; however, a genetic etiology is not found in most cases. In this report, we present two unrelated individuals with semilobar holoprosencephaly who have the identical de novo missense variant in the gene CCR4-NOT transcription complex, subunit 1 (CNOT1). The variant (c.1603C>T [p.Arg535Cys]) is predicted to be deleterious and is not present in public databases. CNOT1 has not been previously associated with holoprosencephaly or other brain malformations. In situ hybridization analyses of mouse embryos show that Cnot1 is expressed in the prosencephalic neural folds at gestational day 8.25 during the critical period for subsequent forebrain division. Combining human and mouse data, we show that CNOT1 is associated with incomplete forebrain division.


Assuntos
Holoprosencefalia/genética , Holoprosencefalia/patologia , Mutação de Sentido Incorreto , Prosencéfalo/anormalidades , Fatores de Transcrição/genética , Animais , Criança , Feminino , Humanos , Lactente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fenótipo , Prosencéfalo/metabolismo
6.
Hum Mutat ; 39(10): 1416-1427, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29992659

RESUMO

Here, we applied targeted capture to examine 153 genes representative of all the major vertebrate developmental pathways among 333 probands to rank their relative significance as causes for holoprosencephaly (HPE). We now show that comparisons of variant transmission versus nontransmission among 136 HPE Trios indicates some reported genes now lack confirmation, while novel genes are implicated. Furthermore, we demonstrate that variation of modest intrinsic effect can synergize with these driver mutations as gene modifiers.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Predisposição Genética para Doença , Proteínas Hedgehog/metabolismo , Holoprosencefalia/genética , Holoprosencefalia/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Fatores de Crescimento de Fibroblastos/genética , Frequência do Gene , Estudos de Associação Genética , Genótipo , Proteínas Hedgehog/genética , Holoprosencefalia/diagnóstico , Humanos , Padrões de Herança , Mutação , Fenótipo , Síndrome , Fator de Crescimento Transformador beta/genética
7.
Hum Mol Genet ; 27(11): 1989-1998, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29584859

RESUMO

The utilization of next generation sequencing has been shown to accelerate gene discovery in human disease. However, our confidence in the correct disease-associations of rare variants continues to depend on functional analysis. Here, we employ a sensitive assay of human FGF8 variants in zebrafish to demonstrate that the spectrum of isoforms of FGF8 produced by alternative splicing can provide key insights into the genetic susceptibility to human malformations. In addition, we describe novel mutations in the FGF core structure that have both subtle and profound effects on ligand posttranslational processing and biological activity. Finally, we solve a case of apparent digenic inheritance of novel variants in SHH and FGF8, two genes known to functionally coregulate each other in the developing forebrain, as a simpler case of FGF8 diminished function.


Assuntos
Processamento Alternativo/genética , Fator 8 de Crescimento de Fibroblasto/genética , Fatores de Crescimento de Fibroblastos/genética , Holoprosencefalia/genética , Proteínas de Peixe-Zebra/genética , Animais , Regulação da Expressão Gênica no Desenvolvimento , Predisposição Genética para Doença , Proteínas Hedgehog/genética , Holoprosencefalia/fisiopatologia , Humanos , Hibridização In Situ , Mutação/genética , Fatores de Risco , Transdução de Sinais/genética , Peixe-Zebra/genética
8.
Biol Psychiatry ; 80(12): 943-954, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27692237

RESUMO

BACKGROUND: Genetic factors predispose individuals to attention-deficit/hyperactivity disorder (ADHD). Previous studies have reported linkage and association to ADHD of gene variants within ADGRL3. In this study, we functionally analyzed noncoding variants in this gene as likely pathological contributors. METHODS: In silico, in vitro, and in vivo approaches were used to identify and characterize evolutionary conserved elements within the ADGRL3 linkage region (~207 Kb). Family-based genetic analyses of 838 individuals (372 affected and 466 unaffected patients) identified ADHD-associated single nucleotide polymorphisms harbored in some of these conserved elements. Luciferase assays and zebrafish green fluorescent protein transgenesis tested conserved elements for transcriptional enhancer activity. Electromobility shift assays were used to verify transcription factor-binding disruption by ADHD risk alleles. RESULTS: An ultraconserved element was discovered (evolutionary conserved region 47) that functions as a transcriptional enhancer. A three-variant ADHD risk haplotype in evolutionary conserved region 47, formed by rs17226398, rs56038622, and rs2271338, reduced enhancer activity by 40% in neuroblastoma and astrocytoma cells (pBonferroni < .0001). This enhancer also drove green fluorescent protein expression in the zebrafish brain in a tissue-specific manner, sharing aspects of endogenous ADGRL3 expression. The rs2271338 risk allele disrupts binding of YY1 transcription factor, an important factor in the development and function of the central nervous system. Expression quantitative trait loci analysis of postmortem human brain tissues revealed an association between rs2271338 and reduced ADGRL3 expression in the thalamus. CONCLUSIONS: These results uncover the first functional evidence of common noncoding variants with potential implications for the pathology of ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Predisposição Genética para Doença , Receptores Acoplados a Proteínas G/genética , Receptores de Peptídeos/genética , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Linhagem , Polimorfismo de Nucleotídeo Único , Adulto Jovem
9.
Hum Mol Genet ; 25(10): 1912-1922, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26931467

RESUMO

Mutations in FGFR1 have recently been associated with Hartsfield syndrome, a clinically distinct syndromic form of holoprosencephaly (HPE) with ectrodactly, which frequently includes combinations of craniofacial, limb and brain abnormalities not typical for classical HPE. Unrelated clinical conditions generally without craniofacial or multi-system malformations include Kallmann syndrome and idiopathic hypogonadotropic hypogonadism. FGFR1 is a principal cause for these less severe diseases as well. Here we demonstrate that of the nine FGFR1 mutations recently detected in our screen of over 200 HPE probands by next generation sequencing, only five distinct mutations in the kinase domain behave as dominant-negative mutations in zebrafish over-expression assays. Three FGFR1 mutations seen in HPE probands behave identical to wild-type FGFR1 in rescue assays, including one apparent de novo variation. Interestingly, in one HPE family, a deleterious FGFR1 allele was transmitted from one parent and a loss-of-function allele in FGF8 from the other parent to both affected daughters. This family is one of the clearest examples to date of gene:gene synergistic interactions causing HPE in humans.


Assuntos
Fenda Labial/genética , Fissura Palatina/genética , Dedos/anormalidades , Predisposição Genética para Doença , Deformidades Congênitas da Mão/genética , Holoprosencefalia/genética , Hipogonadismo/genética , Deficiência Intelectual/genética , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Alelos , Animais , Criança , Pré-Escolar , Fenda Labial/fisiopatologia , Fissura Palatina/fisiopatologia , Modelos Animais de Doenças , Feminino , Dedos/fisiopatologia , Regulação da Expressão Gênica , Genótipo , Deformidades Congênitas da Mão/fisiopatologia , Sequenciamento de Nucleotídeos em Larga Escala , Holoprosencefalia/fisiopatologia , Humanos , Hipogonadismo/patologia , Lactente , Deficiência Intelectual/fisiopatologia , Síndrome de Kallmann/genética , Síndrome de Kallmann/patologia , Masculino , Mutação , Linhagem , Índice de Gravidade de Doença , Peixe-Zebra/genética
10.
Mol Genet Genomic Med ; 3(5): 424-32, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26436108

RESUMO

Limb body wall complex (LBWC) and amniotic band sequence (ABS) are multiple congenital anomaly conditions with craniofacial, limb, and ventral wall defects. LBWC and ABS are considered separate entities by some, and a continuum of severity of the same condition by others. The etiology of LBWC/ABS remains unknown and multiple hypotheses have been proposed. One individual with features of LBWC and his unaffected parents were whole exome sequenced and Sanger sequenced as confirmation of the mutation. Functional studies were conducted using morpholino knockdown studies followed by human mRNA rescue experiments. Using whole exome sequencing, a de novo heterozygous mutation was found in the gene IQCK: c.667C>G; p.Q223E and confirmed by Sanger sequencing in an individual with LBWC. Morpholino knockdown of iqck mRNA in the zebrafish showed ventral defects including failure of ventral fin to develop and cardiac edema. Human wild-type IQCK mRNA rescued the zebrafish phenotype, whereas human p.Q223E IQCK mRNA did not, but worsened the phenotype of the morpholino knockdown zebrafish. This study supports a genetic etiology for LBWC/ABS, or potentially a new syndrome.

11.
PLoS One ; 8(1): e53991, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23342055

RESUMO

BACKGROUND: Fetal Alcohol Spectrum Disorders (FASD) are a collection of disorders resulting from fetal ethanol exposure, which causes a wide range of physical, neurological and behavioral deficits including heightened susceptibility for alcoholism and addictive disorders. While a number of mechanisms have been proposed for how ethanol exposure disrupts brain development, with selective groups of neurons undergoing reduced proliferation, dysfunction and death, the induction of a new neurotransmitter phenotype by ethanol exposure has not yet been reported. PRINCIPAL FINDINGS: The effects of embryonic and larval ethanol exposure on brain development were visually monitored using transgenic zebrafish expressing cell-specific green fluorescent protein (GFP) marker genes. Specific subsets of GFP-expressing neurons were highly sensitive to ethanol exposure, but only during defined developmental windows. In the med12 mutant, which affects the Mediator co-activator complex component Med12, exposure to lower concentrations of ethanol was sufficient to reduce GFP expression in transgenic embryos. In transgenic embryos and larva containing GFP driven by an oxytocin-like (oxtl) promoter, ethanol exposure dramatically up-regulated GFP expression in a small group of hindbrain neurons, while having no effect on expression in the neuroendocrine preoptic area. CONCLUSIONS: Alcohol exposure during limited embryonic periods impedes the development of specific, identifiable groups of neurons, and the med12 mutation sensitizes these neurons to the deleterious effects of ethanol. In contrast, ethanol exposure induces oxtl expression in the hindbrain, a finding with profound implications for understanding alcoholism and other addictive disorders.


Assuntos
Etanol/farmacologia , Imagem Molecular , Neurônios/efeitos dos fármacos , Ocitocina/genética , Rombencéfalo/efeitos dos fármacos , Ativação Transcricional/efeitos dos fármacos , Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Genes Reporter/genética , Neurônios/metabolismo , Regiões Promotoras Genéticas/genética , Rombencéfalo/citologia , Rombencéfalo/embriologia , Rombencéfalo/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo
12.
PLoS One ; 7(7): e39026, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22859937

RESUMO

Coding region alterations of ZIC2 are the second most common type of mutation in holoprosencephaly (HPE). Here we use several complementary bioinformatic approaches to identify ultraconserved cis-regulatory sequences potentially driving the expression of human ZIC2. We demonstrate that an 804 bp element in the 3' untranslated region (3'UTR) is highly conserved across the evolutionary history of vertebrates from fish to humans. Furthermore, we show that while genetic variation of this element is unexpectedly common among holoprosencephaly subjects (6/528 or >1%), it is not present in control individuals. Two of six proband-unique variants are de novo, supporting their pathogenic involvement in HPE outcomes. These findings support a general recommendation that the identification and analysis of key ultraconserved elements should be incorporated into the genetic risk assessment of holoprosencephaly cases.


Assuntos
Regiões 3' não Traduzidas , Holoprosencefalia/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genética , Animais , Sequência de Bases , Padronização Corporal , Sequência Conservada , Análise Mutacional de DNA , Redes Reguladoras de Genes , Estudos de Associação Genética , Humanos , Dados de Sequência Molecular , Prosencéfalo/crescimento & desenvolvimento , Alinhamento de Sequência , Peixe-Zebra
13.
PLoS One ; 6(4): e19076, 2011 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-21533047

RESUMO

BACKGROUND: Rhombomere boundaries form during hindbrain segmentation and are critical for maintaining segmental integrity and regulating migration in the hindbrain. Some genetic models affecting hindbrain boundary formation have been described, but involvement of components of the transcriptional mediator complex in boundary formation has not reported so far. PRINCIPAL FINDINGS: The kto/med12 mutant zebrafish, which affects the Mediator component Med12, causes specific loss of rhombomere boundary cells even though segmentation of the hindbrain takes place at least in part. In kto mutant embryos, cells forming rhombomere boundaries were largely absent as indicated by the use of several marker genes. While no obvious increase in cell death was observed, we found a notable reduction of cell proliferation in the hindbrain of kto mutant zebrafish. CONCLUSIONS: The kto/med12 mutation results in specific defects of boundary cell formation in the zebrafish hindbrain.


Assuntos
Complexo Mediador/fisiologia , Rombencéfalo/embriologia , Proteínas de Peixe-Zebra/fisiologia , Peixe-Zebra/embriologia , Animais , Padronização Corporal , Proliferação de Células , Complexo Mediador/genética , Mutação , Rombencéfalo/citologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
14.
PLoS One ; 6(4): e18858, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21526205

RESUMO

In the vertebrate embryo, the kidney is derived from the intermediate mesoderm. The LIM-class homeobox transcription factor lhx1 is expressed early in the intermediate mesoderm and is one of the first genes to be expressed in the nephric mesenchyme. In this study, we investigated the role of Lhx1 in specification of the kidney field by either overexpressing or depleting lhx1 in Xenopus embryos or depleting lhx1 in an explant culture system. By overexpressing a constitutively-active form of Lhx1, we established its capacity to expand the kidney field during the specification stage of kidney organogenesis. In addition, the ability of Lhx1 to expand the kidney field diminishes as kidney organogenesis transitions to the morphogenesis stage. In a complimentary set of experiments, we determined that embryos depleted of lhx1, show an almost complete loss of the kidney field. Using an explant culture system to induce kidney tissue, we confirmed that expression of genes from both proximal and distal kidney structures is affected by the absence of lhx1. Taken together our results demonstrate an essential role for Lhx1 in driving specification of the entire kidney field from the intermediate mesoderm.


Assuntos
Padronização Corporal , Proteínas de Homeodomínio/metabolismo , Rim/citologia , Células-Tronco/citologia , Proteínas de Xenopus/metabolismo , Animais , Padronização Corporal/genética , Proliferação de Células , Embrião não Mamífero/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Inativação Gênica , Proteínas de Homeodomínio/genética , Proteínas com Homeodomínio LIM , Mesoderma/citologia , Análise de Sequência com Séries de Oligonucleotídeos , Oligonucleotídeos Antissenso/farmacologia , Técnicas de Cultura de Órgãos , Células-Tronco/metabolismo , Fatores de Tempo , Fatores de Transcrição , Xenopus/embriologia , Xenopus/genética , Proteínas de Xenopus/deficiência , Proteínas de Xenopus/genética
15.
Development ; 138(4): 787-95, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21266414

RESUMO

Vertebrate mesoderm and endoderm formation requires signaling by Nodal-related ligands from the TGFß superfamily. The factors that initiate Nodal-related gene transcription are unknown in most species and the relative contributions of Nodal-related ligands from embryonic, extraembryonic and maternal sources remain uncertain. In zebrafish, signals from the yolk syncytial layer (YSL), an extraembryonic domain, are required for mesoderm and endoderm induction, and YSL expression of nodal-related 1 (ndr1) and ndr2 accounts for a portion of this activity. A variable requirement of maternally derived Ndr1 for dorsal and anterior axis formation has also been documented. Here we show that Mxtx2 directly activates expression of ndr2 via binding to its first intron and is required for ndr2 expression in the YSL. Mxtx2 is also required for the Nodal signaling-independent expression component of the no tail a (ntla) gene, which is required for posterior (tail) mesoderm formation. Therefore, Mxtx2 defines a new pathway upstream of Nodal signaling and posterior mesoderm formation. We further show that the co-disruption of extraembryonic Ndr2, extraembryonic Ndr1 and maternal Ndr1 eliminates endoderm and anterior (head and trunk) mesoderm, recapitulating the loss of Nodal signaling phenotype. Therefore, non-embryonic sources of Nodal-related ligands account for the complete spectrum of early Nodal signaling requirements. In summary, the induction of mesoderm and endoderm depends upon the combined actions of Mxtx2 and Nodal-related ligands from non-embryonic sources.


Assuntos
Embrião não Mamífero/metabolismo , Endoderma/metabolismo , Proteínas de Homeodomínio/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Mesoderma/metabolismo , Ligantes da Sinalização Nodal/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/metabolismo , Animais , Regulação da Expressão Gênica no Desenvolvimento , Proteínas de Homeodomínio/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Ligantes , Ligantes da Sinalização Nodal/genética , Transcrição Gênica , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Proteínas de Peixe-Zebra/genética
16.
Int J Dev Biol ; 55(10-12): 917-21, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22252488

RESUMO

Immediate early response 2 (Ier2) is a downstream target of fibroblast growth factor (FGF) signaling. In zebrafish, Ier2 is involved in left-right asymmetry establishment and in convergent extension movements. We isolated the Xenopus ier2 gene based on sequence similarity searches using multiple vertebrate species. Xenopus Ier2 has high homology in the N-terminal region to other vertebrate Ier2 proteins, and Xier2 transcripts were observed from oocytes through larval stages. Except for the maternal expression of xier2, the expression of this gene in the marginal region at gastrulation and in somites and the notochord at later stages is similar to the expression pattern of zebrafish ier2. XIer2 knockdown using antisense morpholinos resulted in defects of convergent extension leading to severe neural tube defects; overexpression of Ier2 showed similar, albeit milder phenotypes. Assays in animal cap explants likewise showed inhibition of elongation after blocking XIer2 expression. These results indicate that Xenopus Ier2 is essential for the execution of convergent extension movements during early Xenopus development.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Proteínas Imediatamente Precoces/genética , Proteínas de Xenopus/genética , Sequência de Aminoácidos , Animais , DNA Complementar/metabolismo , Fatores de Crescimento de Fibroblastos/metabolismo , Perfilação da Expressão Gênica , Modelos Genéticos , Dados de Sequência Molecular , Oligonucleotídeos Antissenso/genética , Oócitos/citologia , Fenótipo , Filogenia , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Xenopus , Xenopus laevis
17.
Genes Cells ; 15(11): 1099-110, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20977546

RESUMO

Angiogenesis plays an important role in vertebrate development and tumor growth. In this process, gicerin, which is known as a kind of cell adhesion molecule, has recently been reported to play an important role but its in vivo function is still unclear in developing vasculature. To address this issue, we used gain-of-function and loss-of-function analyses of gicerin in zebrafish. In the gain of function experiments using enforced expression of various domains of gicerin constructs, extracellular domain induced angiogenic sprouting defects, most notably in the intersegmental vessels, whereas the cytoplasmic domain of gicerin did not affect angiogenic sprouting. Moreover, morpholino-mediated knockdown of gicerin in embryos resulted in angiogenic sprouting defects in intersegmental vessels. Mechanistically, the angiogenic function of gicerin was found to be genetically linked to VEGF signaling in the knock-down experiments using vegf-a mRNA, VEGFR inhibitor and gicerin morpholino. In addition to the physiological angiogenesis during development, gicerin morphants efficiently blocked the tumor angiogenesis in zebrafish. Thus, knock-down of gicerin might have an important implication in controlling tumor angiogenesis.


Assuntos
Antígeno CD146/fisiologia , Neoplasias/irrigação sanguínea , Neovascularização Patológica/metabolismo , Neovascularização Fisiológica , Animais , Animais Geneticamente Modificados , Vasos Sanguíneos/embriologia , Vasos Sanguíneos/metabolismo , Embrião não Mamífero/metabolismo , Técnicas de Silenciamento de Genes , Hibridização In Situ , Microinjeções , Neoplasias/metabolismo , Neovascularização Fisiológica/fisiologia , Oligonucleotídeos Antissenso/administração & dosagem , Oligonucleotídeos Antissenso/farmacologia , Transdução de Sinais , Fatores de Crescimento do Endotélio Vascular/metabolismo , Peixe-Zebra
18.
BMC Dev Biol ; 10: 42, 2010 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-20423468

RESUMO

BACKGROUND: Many species form extraembryonic tissues during embryogenesis, such as the placenta of humans and other viviparous mammals. Extraembryonic tissues have various roles in protecting, nourishing and patterning embryos. Prior to gastrulation in zebrafish, the yolk syncytial layer - an extraembryonic nuclear syncytium - produces signals that induce mesoderm and endoderm formation. Mesoderm and endoderm precursor cells are situated in the embryonic margin, an external ring of cells along the embryo-yolk interface. The yolk syncytial layer initially forms below the margin, in a domain called the external yolk syncytial layer (E-YSL). RESULTS: We hypothesize that key components of the yolk syncytial layer's mesoderm and endoderm inducing activity are expressed as mRNAs in the E-YSL. To identify genes expressed in the E-YSL, we used microarrays to compare the transcription profiles of intact pre-gastrula embryos with pre-gastrula embryonic cells that we had separated from the yolk and yolk syncytial layer. This identified a cohort of genes with enriched expression in intact embryos. Here we describe our whole mount in situ hybridization analysis of sixty-eight of them. This includes ten genes with E-YSL expression (camsap1l1, gata3, znf503, hnf1ba, slc26a1, slc40a1, gata6, gpr137bb, otop1 and cebpa), four genes with expression in the enveloping layer (EVL), a superficial epithelium that protects the embryo (zgc:136817, zgc:152778, slc14a2 and elovl6l), three EVL genes whose expression is transiently confined to the animal pole (elovl6l, zgc:136359 and clica), and six genes with transient maternal expression (mtf1, wu:fj59f04, mospd2, rftn2, arrdc1a and pho). We also assessed the requirement of Nodal signaling for the expression of selected genes in the E-YSL, EVL and margin. Margin expression was Nodal dependent for all genes we tested, including the concentrated margin expression of an EVL gene: zgc:110712. All other instances of EVL and E-YSL expression that we tested were Nodal independent. CONCLUSION: We have devised an effective strategy for enriching and identifying genes expressed in the E-YSL of pre-gastrula embryos. To our surprise, maternal genes and genes expressed in the EVL were also enriched by this strategy. A number of these genes are promising candidates for future functional studies on early embryonic patterning.


Assuntos
Embrião não Mamífero/metabolismo , Membranas Extraembrionárias/metabolismo , Perfilação da Expressão Gênica , Peixe-Zebra/embriologia , Animais , Gema de Ovo/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos
19.
Proc Natl Acad Sci U S A ; 106(7): 2230-5, 2009 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-19164561

RESUMO

Establishment of left-right asymmetry in vertebrates requires nodal, Wnt-PCP and FGF signaling and involves ciliogenesis in a laterality organ. Effector genes through which FGF signaling affects laterality have not been described. We isolated the zebrafish ier2 and fibp1 genes as FGF target genes and show that their protein products interact. Knock down of these factors interferes with establishment of organ laterality and causes defective cilia formation in Kupffer's Vesicle, the zebrafish laterality organ. Cilia are also lost after suppression of FGF8, but can be rescued by injection of ier2 and fibp1 mRNA. We conclude that Ier2 and Fibp1 mediate FGF signaling in ciliogenesis in Kupffer's Vesicle and in the establishment of laterality in the zebrafish embryo.


Assuntos
Padronização Corporal , Proteínas de Transporte/fisiologia , Fatores de Crescimento de Fibroblastos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Proteínas Imediatamente Precoces/fisiologia , Proteínas de Peixe-Zebra/metabolismo , Animais , Proteínas de Transporte/genética , Linhagem Celular , Biologia do Desenvolvimento , Humanos , Proteínas Imediatamente Precoces/genética , Hibridização In Situ , Modelos Biológicos , Fenótipo , RNA Mensageiro/metabolismo , Técnicas do Sistema de Duplo-Híbrido , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/fisiologia
20.
PLoS One ; 3(11): e3736, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19011686

RESUMO

BACKGROUND: Alpha 2 Macroglobulin family members have been studied extensively with respect to their roles in physiology and human disease including innate immunity and Alzheimer's disease, but little is known about a possible role in liver development loss-of-function in model systems. PRINCIPAL FINDINGS: We report the isolation of the zebrafish alpha2 macroglobulin-like (A2ML) gene and its specific expression in the liver during differentiation. Morpholino-based knock-down of A2ML did not block the initial formation of the liver primordium, but inhibited liver growth and differentiation. SIGNIFICANCE: This report on A2ML function in zebrafish development provides the first evidence for a specific role of an A2M family gene in liver formation during early embryogenesis in a vertebrate.


Assuntos
Fígado/embriologia , Fígado/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , alfa-Macroglobulinas/genética , Animais , Proliferação de Células , Embrião não Mamífero/citologia , Embrião não Mamífero/efeitos dos fármacos , Embrião não Mamífero/metabolismo , Trato Gastrointestinal/embriologia , Trato Gastrointestinal/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Hepatócitos/citologia , Hibridização In Situ , Marcação In Situ das Extremidades Cortadas , Fígado/citologia , Oligonucleotídeos Antissenso/farmacologia , Especificidade de Órgãos , Organogênese , Pâncreas/embriologia , Pâncreas/metabolismo , Fenótipo , Filogenia , alfa-Macroglobulinas/metabolismo
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