Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Genome Res ; 21(2): 325-41, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21177967

RESUMO

The C. elegans genome has been completely sequenced, and the developmental anatomy of this model organism is described at single-cell resolution. Here we utilize strategies that exploit this precisely defined architecture to link gene expression to cell type. We obtained RNAs from specific cells and from each developmental stage using tissue-specific promoters to mark cells for isolation by FACS or for mRNA extraction by the mRNA-tagging method. We then generated gene expression profiles of more than 30 different cells and developmental stages using tiling arrays. Machine-learning-based analysis detected transcripts corresponding to established gene models and revealed novel transcriptionally active regions (TARs) in noncoding domains that comprise at least 10% of the total C. elegans genome. Our results show that about 75% of transcripts with detectable expression are differentially expressed among developmental stages and across cell types. Examination of known tissue- and cell-specific transcripts validates these data sets and suggests that newly identified TARs may exercise cell-specific functions. Additionally, we used self-organizing maps to define groups of coregulated transcripts and applied regulatory element analysis to identify known transcription factor- and miRNA-binding sites, as well as novel motifs that likely function to control subsets of these genes. By using cell-specific, whole-genome profiling strategies, we have detected a large number of novel transcripts and produced high-resolution gene expression maps that provide a basis for establishing the roles of individual genes in cellular differentiation.


Assuntos
Caenorhabditis elegans/genética , Regulação da Expressão Gênica no Desenvolvimento , Animais , Biologia Computacional , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/genética , Masculino , Meiose/genética , Dados de Sequência Molecular , Oogênese/genética , Fases de Leitura Aberta/genética , Transcrição Gênica , Regiões não Traduzidas/genética , Inativação do Cromossomo X/genética
2.
Proc Natl Acad Sci U S A ; 108(1): 254-9, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21173231

RESUMO

CO(2) is both a critical regulator of animal physiology and an important sensory cue for many animals for host detection, food location, and mate finding. The free-living soil nematode Caenorhabditis elegans shows CO(2) avoidance behavior, which requires a pair of ciliated sensory neurons, the BAG neurons. Using in vivo calcium imaging, we show that CO(2) specifically activates the BAG neurons and that the CO(2)-sensing function of BAG neurons requires TAX-2/TAX-4 cyclic nucleotide-gated ion channels and the receptor-type guanylate cyclase GCY-9. Our results delineate a molecular pathway for CO(2) sensing and suggest that activation of a receptor-type guanylate cyclase is an evolutionarily conserved mechanism by which animals detect environmental CO(2).


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/fisiologia , Dióxido de Carbono/metabolismo , Quimiotaxia/fisiologia , Guanilato Ciclase/metabolismo , Canais Iônicos/metabolismo , Neurônios/metabolismo , Receptores Acoplados a Guanilato Ciclase/metabolismo , Olfato/fisiologia , Animais , Sequência de Bases , Evolução Biológica , Caenorhabditis elegans/enzimologia , Dióxido de Carbono/toxicidade , Quimiotaxia/efeitos dos fármacos , Análise por Conglomerados , Primers do DNA/genética , Componentes do Gene , Microscopia Confocal , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Olfato/genética , Transgenes/genética
3.
Neuron ; 100(6): 1414-1428.e10, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30392795

RESUMO

Finding food and remaining at a food source are crucial survival strategies. We show how neural circuits and signaling molecules regulate these food-related behaviors in Caenorhabditis elegans. In the absence of food, AVK interneurons release FLP-1 neuropeptides that inhibit motorneurons to regulate body posture and velocity, thereby promoting dispersal. Conversely, AVK photoinhibition promoted dwelling behavior. We identified FLP-1 receptors required for these effects in distinct motoneurons. The DVA interneuron antagonizes signaling from AVK by releasing cholecystokinin-like neuropeptides that potentiate cholinergic neurons, in response to dopaminergic neurons that sense food. Dopamine also acts directly on AVK via an inhibitory dopamine receptor. Both AVK and DVA couple to head motoneurons by electrical and chemical synapses to orchestrate either dispersal or dwelling behavior, thus integrating environmental and proprioceptive signals. Dopaminergic regulation of food-related behavior, via similar neuropeptides, may be conserved in mammals.


Assuntos
Dopamina/farmacologia , Alimentos , Locomoção/efeitos dos fármacos , Vias Neurais/fisiologia , Neuropeptídeos/farmacologia , Sensação/fisiologia , Células Receptoras Sensoriais/efeitos dos fármacos , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Cálcio/metabolismo , Channelrhodopsins/genética , Channelrhodopsins/metabolismo , Dopamina/metabolismo , Vias Neurais/efeitos dos fármacos , Neuropeptídeos/metabolismo , Optogenética , Receptores Dopaminérgicos/genética , Receptores Dopaminérgicos/fisiologia , Células Receptoras Sensoriais/fisiologia
4.
Elife ; 52016 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-27697151

RESUMO

The ability of a neuron to regenerate its axon after injury depends in part on its intrinsic regenerative potential. Here, we identify novel intrinsic regulators of axon regeneration: poly(ADP-ribose) glycohodrolases (PARGs) and poly(ADP-ribose) polymerases (PARPs). PARGs, which remove poly(ADP-ribose) from proteins, act in injured C. elegans GABA motor neurons to enhance axon regeneration. PARG expression is regulated by DLK signaling, and PARGs mediate DLK function in enhancing axon regeneration. Conversely, PARPs, which add poly(ADP-ribose) to proteins, inhibit axon regeneration of both C. elegans GABA neurons and mammalian cortical neurons. Furthermore, chemical PARP inhibitors improve axon regeneration when administered after injury. Our results indicate that regulation of poly(ADP-ribose) levels is a critical function of the DLK regeneration pathway, that poly-(ADP ribosylation) inhibits axon regeneration across species, and that chemical inhibition of PARPs can elicit axon regeneration.


Assuntos
ADP Ribose Transferases/metabolismo , Axônios/fisiologia , Glicosídeo Hidrolases/metabolismo , Poli ADP Ribosilação , Regeneração , Animais , Caenorhabditis elegans/enzimologia , Caenorhabditis elegans/fisiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA