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1.
Cell ; 167(5): 1252-1263.e10, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27863243

RESUMO

Many animal tissues/cells are photosensitive, yet only two types of photoreceptors (i.e., opsins and cryptochromes) have been discovered in metazoans. The question arises as to whether unknown types of photoreceptors exist in the animal kingdom. LITE-1, a seven-transmembrane gustatory receptor (GR) homolog, mediates UV-light-induced avoidance behavior in C. elegans. However, it is not known whether LITE-1 functions as a chemoreceptor or photoreceptor. Here, we show that LITE-1 directly absorbs both UVA and UVB light with an extinction coefficient 10-100 times that of opsins and cryptochromes, indicating that LITE-1 is highly efficient in capturing photons. Unlike typical photoreceptors employing a prosthetic chromophore to capture photons, LITE-1 strictly depends on its protein conformation for photon absorption. We have further identified two tryptophan residues critical for LITE-1 function. Interestingly, unlike GPCRs, LITE-1 adopts a reversed membrane topology. Thus, LITE-1, a taste receptor homolog, represents a distinct type of photoreceptor in the animal kingdom.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/metabolismo , Proteínas de Membrana/metabolismo , Animais , Caenorhabditis elegans/efeitos da radiação , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/isolamento & purificação , Proteínas de Membrana/química , Proteínas de Membrana/isolamento & purificação , Fótons , Conformação Proteica , Triptofano/metabolismo , Raios Ultravioleta
3.
Neuroimage ; 285: 120499, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38097055

RESUMO

Anxious depression is a common subtype of major depressive disorder (MDD) associated with adverse outcomes and severely impaired social function. It is important to clarify the underlying neurobiology of anxious depression to refine the diagnosis and stratify patients for therapy. Here we explored associations between anxiety and brain structure/function in MDD patients. A total of 260 MDD patients and 127 healthy controls underwent three-dimensional T1-weighted structural scanning and resting-state functional magnetic resonance imaging. Demographic data were collected from all participants. Differences in gray matter volume (GMV), (fractional) amplitude of low-frequency fluctuation ((f)ALFF), regional homogeneity (ReHo), and seed point-based functional connectivity were compared between anxious MDD patients, non-anxious MDD patients, and healthy controls. A random forest model was used to predict anxiety in MDD patients using neuroimaging features. Anxious MDD patients showed significant differences in GMV in the left middle temporal gyrus and ReHo in the right superior parietal gyrus and the left precuneus than HCs. Compared with non-anxious MDD patients, patients with anxious MDD showed significantly different GMV in the left inferior temporal gyrus, left superior temporal gyrus, left superior frontal gyrus (orbital part), and left dorsolateral superior frontal gyrus; fALFF in the left middle temporal gyrus; ReHo in the inferior temporal gyrus and the superior frontal gyrus (orbital part); and functional connectivity between the left superior temporal gyrus(temporal pole) and left medial superior frontal gyrus. A diagnostic predictive random forest model built using imaging features and validated by 10-fold cross-validation distinguished anxious from non-anxious MDD with an AUC of 0.802. Patients with anxious depression exhibit dysregulation of brain regions associated with emotion regulation, cognition, and decision-making, and our diagnostic model paves the way for more accurate, objective clinical diagnosis of anxious depression.


Assuntos
Transtorno Depressivo Maior , Humanos , Depressão , Imageamento por Ressonância Magnética/métodos , Encéfalo , Neuroimagem , Aprendizado de Máquina
4.
PLoS Genet ; 17(1): e1009295, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33428618

RESUMO

Environmental factors such as temperature affect neuronal activity and development. However, it remains unknown whether and how they affect synaptic subcellular specificity. Here, using the nematode Caenorhabditis elegans AIY interneurons as a model, we found that high cultivation temperature robustly induces defects in synaptic subcellular specificity through glutamatergic neurotransmission. Furthermore, we determined that the functional glutamate is mainly released by the ASH sensory neurons and sensed by two conserved inhibitory glutamate-gated chloride channels GLC-3 and GLC-4 in AIY. Our work not only presents a novel neurotransmission-dependent mechanism underlying the synaptic subcellular specificity, but also provides a potential mechanistic insight into high-temperature-induced neurological defects.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Canais de Cloreto/genética , Ácido Glutâmico/metabolismo , Interneurônios/metabolismo , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/fisiologia , Ácido Glutâmico/genética , Transdução de Sinais/genética , Sinapses/genética , Sinapses/metabolismo , Transmissão Sináptica/genética , Temperatura
5.
BMC Psychiatry ; 23(1): 949, 2023 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-38104061

RESUMO

BACKGROUND: Insomnia symptoms in patients with major depressive disorder (MDD) are common and deleterious. Childhood trauma, personality traits, interpersonal distress, and social support contribute to insomnia, but how they interact to affect insomnia remains uncertain. METHODS: A total of 791 patients with MDD completed the Insomnia Severity Index, Eysenck Personality Questionnaire, Interpersonal Relationship Comprehensive Diagnostic Scale, Childhood Trauma Questionnaire, Social Support Rating Scale and Hamilton Depression Scale-17. This study utilized network analyses to identify the central symptoms of insomnia and their associations with psychosocial factors. RESULTS: Worrying about sleep was identified as the central symptom in the insomnia network, insomnia and associated personality network, insomnia and associated interpersonal disturbance network, insomnia and associated childhood trauma network, insomnia and associated social support network, and the integrated network of insomnia symptoms and associated psychosocial factors. In the networks of insomnia symptoms and individual psychosocial factors, most psychosocial factors (other than childhood trauma) were directly or indirectly related to insomnia symptoms; however, neuroticism was the only factor directly associated with insomnia symptoms before and after controlling for covariates. In the final integrated network of insomnia symptoms and psychosocial factors, neuroticism was a bridge node and mediated the relationships of social support and interpersonal disturbances with insomnia symptoms, which is clearly presented in the shortest pathways. CONCLUSIONS: Worrying about sleep and neuroticism were prominent in the integrated network of insomnia symptoms and associated psychosocial factors, and the edge between them connected psychosocial factors and insomnia symptoms in MDD patients.


Assuntos
Transtorno Depressivo Maior , Distúrbios do Início e da Manutenção do Sono , Humanos , Depressão/complicações , Depressão/psicologia , Distúrbios do Início e da Manutenção do Sono/complicações , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/psicologia , Personalidade
6.
J Nurs Manag ; 30(6): 1949-1959, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35509174

RESUMO

AIM: This study aimed to investigate eHealth literacy about coronavirus disease 2019 (COVID-19) among older adults during the pandemic. BACKGROUND: The COVID-19 pandemic promoted the development of online health care. Higher demand for accessing information from the Internet was seen. METHODS: This was a sequential explanatory mixed-method study, involving a survey of older adults to explore the status and influencing factors of eHealth literacy regarding COVID-19. Semi-structured interviews were used to understand experiences and challenges regarding information retrieval, judgment and utilization. RESULTS: A total of 337 older adults participated in the online questionnaire survey. Overall, older adults had slightly higher scores on eHealth literacy during the COVID-19 pandemic. Participants' location in the past month and current health issues were associated with eHealth literacy. Qualitative data were collected from nine older adults and included that some older adults retrieved health-related information during the pandemic. However, those who used non-smartphones described difficulties in information retrieval. A glut of misinformation has resulted in an 'infodemic', which has not only increased the difficulty of judging information but also posed challenges in information utilization for older adults. CONCLUSION: Improving older adults' eHealth literacy is essential in promoting an improved response to major public health events and in providing better health care for this group in the future. It is essential that government health agencies and health care providers provide evidence-based health information via social media platforms. Further efforts are needed to combine aspects of traditional and online health care services and provide reliable and updated online information and resources for older adults. IMPLICATIONS FOR NURSING MANAGEMENT: Providing evidence to eHealth literacy improvement and health management of older adults in the context of public health events.


Assuntos
COVID-19 , Letramento em Saúde , Idoso , COVID-19/epidemiologia , Estudos Transversais , Eletrônica , Humanos , Internet , Pandemias , Inquéritos e Questionários
7.
Neural Plast ; 2021: 2348072, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34462632

RESUMO

At present, the etiology and pathogenesis of major depressive disorder (MDD) are still not clear. Studies have found that the risk of first-degree relatives of MDD is 2-3 times that of the general population. Diffusion tensor imaging (DTI) has been previously used to explore the pathogenesis of MDD. The purpose of this study is to explore the etiology of MDD by DTI and further to explore the correlation between its clinical characteristics and the structural changes of white matter in the brain. The study included 27 first-episode, drug-naive patients with MDD, 16 first-degree relatives without MDD, and 28 healthy control subjects with no family history of MDD (HC). Results showed that the fractional anisotropy (FA) differences among the three groups were mainly in the left anterior thalamic radiation (LATR), right anterior thalamic radiation (RATR), left corticospinal tracts (LCST), forceps major (FMa), right inferior longitudinal fasciculus (RILF), and left superior longitudinal fasciculus (temporal) (LSLF(T)). Among the 6 sites, LCST, FMa, and LSLF(T) showed significant differences between MDD and First-degree relatives compared to HC. MDD patients had significant emotional symptoms, somatic symptoms, and cognitive impairment. FMa FA was significantly positively correlated with delayed memory score (r = 0.43, P = 0.031), and RILF FA was significantly negatively correlated with the FSS score (r = -0.42, P = 0.028). These results revealed that the white matter characteristics of MDD-susceptible patients were LCST, FMa, and LSLF(T) lesions, all of which may be quality indicators of MDD.


Assuntos
Transtorno Depressivo Maior/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Tratos Piramidais/diagnóstico por imagem , Indicadores de Qualidade em Assistência à Saúde , Tálamo/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Masculino , Adulto Jovem
8.
Neural Plast ; 2021: 7088856, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335734

RESUMO

Suicidal ideation (SI) is a direct risk factor for suicide in patients with depression. Regarding the emergence of SI, previous studies have discovered many risk factors, including childhood abuse as the major public problem. Previous imaging studies have demonstrated that SI or childhood abuse has effects on brain structure and function, respectively, but the interaction effects between them have not been fully studied. To explore the interaction effect between SI and childhood abuse, 215 patients with major depressive disorder completed the Childhood Trauma Questionnaire to evaluate childhood abuse and Beck's Scale for Suicidal Ideation to evaluate SI. Then, they completed magnetic resonance imaging (MRI) within one week after completing questionnaires. Respectively, we preprocessed the structural and functional images and analyzed gray matter volumes (GMV) and mean fractional amplitude of low-frequency fluctuation (mfALFF) values. Results showed that the changes of GMV in the cuneus, precuneus, paracentric lobule, inferior frontal gyrus, and caudate nucleus and local activity in cuneal and middle temporal gyrus are in relation with SI and childhood abuse. And in left caudate, SI and childhood abuse interact with each other on the influence of GMV. That is, the influence of SI in GMV was related to childhood abuse, and the influence of childhood abuse in GMV was also related to SI. Therefore, the combination of SI and childhood abuse based on imaging should help us better understand the suicide ideation developing mechanism and propose more effective targeted prevention strategies for suicide prevention.


Assuntos
Sobreviventes Adultos de Maus-Tratos Infantis , Encéfalo/efeitos dos fármacos , Transtorno Depressivo Maior/diagnóstico por imagem , Ideação Suicida , Adulto , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão/fisiologia , Adulto Jovem
9.
J Neurogenet ; 34(3-4): 363-368, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33325279

RESUMO

Mechanosensation such as touch, hearing and proprioception, is functionally regulated by mechano-gated ion channels through the process of transduction. Mechano-gated channels are a subtype of gated ion channels engaged in converting mechanical stimuli to chemical or electrical signals thereby modulating sensation. To date, a few families of mechano-gated channels (DEG/ENaC, TRPN, K2P, TMC and Piezo) have been identified in eukaryotes. Using a tractable genetic model organism Caenorhabditis elegans, the molecular mechanism of mechanosensation have been the focus of much research to comprehend the process of mechanotransduction. Comprising of almost all metazoans classes of ion channels, transporters and receptors, C. elegans is a powerful genetic model to explore mechanosensitive behaviors such as touch sensation and proprioception. The nematode relies primarily on its sensory abilities to survive in its natural environment. Genetic screening, calcium imaging and electrophysiological analysis have established that ENaC proteins and TRPN channel (TRP-4 protein) can characterize mechano-gated channels in C. elegans. A recent study reported that TMCs are likely the pore-forming subunit of a mechano-gated channel in C. elegans. Nevertheless, it still remains unclear whether Piezo as well as other candidate proteins can form mechano-gated channels in C. elegans.


Assuntos
Proteínas de Caenorhabditis elegans/fisiologia , Caenorhabditis elegans/fisiologia , Mecanorreceptores/fisiologia , Mecanotransdução Celular/fisiologia , Animais , Caenorhabditis elegans/citologia , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Genes de Helmintos , Ativação do Canal Iônico/fisiologia , Canais Iônicos/classificação , Canais Iônicos/genética , Canais Iônicos/fisiologia , Mamíferos/fisiologia , Família Multigênica , Especificidade da Espécie
10.
Brain Behav Immun ; 87: 11-17, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32240764

RESUMO

The severe 2019 outbreak of novel coronavirus disease (COVID-19), which was first reported in Wuhan, would be expected to impact the mental health of local medical and nursing staff and thus lead them to seek help. However, those outcomes have yet to be established using epidemiological data. To explore the mental health status of medical and nursing staff and the efficacy, or lack thereof, of critically connecting psychological needs to receiving psychological care, we conducted a quantitative study. This is the first paper on the mental health of medical and nursing staff in Wuhan. Notably, among 994 medical and nursing staff working in Wuhan, 36.9% had subthreshold mental health disturbances (mean PHQ-9: 2.4), 34.4% had mild disturbances (mean PHQ-9: 5.4), 22.4% had moderate disturbances (mean PHQ-9: 9.0), and 6.2% had severe disturbance (mean PHQ-9: 15.1) in the immediate wake of the viral epidemic. The noted burden fell particularly heavily on young women. Of all participants, 36.3% had accessed psychological materials (such as books on mental health), 50.4% had accessed psychological resources available through media (such as online push messages on mental health self-help coping methods), and 17.5% had participated in counseling or psychotherapy. Trends in levels of psychological distress and factors such as exposure to infected people and psychological assistance were identified. Although staff accessed limited mental healthcare services, distressed staff nonetheless saw these services as important resources to alleviate acute mental health disturbances and improve their physical health perceptions. These findings emphasize the importance of being prepared to support frontline workers through mental health interventions at times of widespread crisis.


Assuntos
Transtornos de Ansiedade/psicologia , Infecções por Coronavirus/terapia , Transtorno Depressivo/psicologia , Enfermeiras e Enfermeiros/psicologia , Médicos/psicologia , Pneumonia Viral/terapia , Distúrbios do Início e da Manutenção do Sono/psicologia , Adaptação Psicológica , Adolescente , Adulto , Ansiedade/epidemiologia , Ansiedade/psicologia , Transtornos de Ansiedade/epidemiologia , Betacoronavirus , COVID-19 , China/epidemiologia , Infecções por Coronavirus/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Depressão/psicologia , Transtorno Depressivo/epidemiologia , Surtos de Doenças , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Saúde Mental , Serviços de Saúde Mental , Pessoa de Meia-Idade , Enfermeiras e Enfermeiros/estatística & dados numéricos , Pandemias , Questionário de Saúde do Paciente , Médicos/estatística & dados numéricos , Pneumonia Viral/epidemiologia , Angústia Psicológica , SARS-CoV-2 , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Inquéritos e Questionários , Adulto Jovem
11.
Cell Mol Life Sci ; 76(21): 4221-4232, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31584127

RESUMO

In the past two decades, transmembrane channel-like (TMC) proteins have attracted a significant amount of research interest, because mutations of Tmc1 lead to hereditary deafness. As evolutionarily conserved membrane proteins, TMC proteins are widely involved in diverse sensorimotor functions of many species, such as hearing, chemosensation, egg laying, and food texture detection. Interestingly, recent structural and physiological studies suggest that TMC channels may share a similar membrane topology with the Ca2+-activated Cl- channel TMEM16 and the mechanically activated OSCA1.2/TMEM63 channel. Namely, these channels form dimers and each subunit consists of ten transmembrane segments. Despite this important structural insight, a key question remains: what is the gating mechanism of TMC channels? The major technical hurdle to answer this question is that the reconstitution of TMC proteins as functional ion channels has been challenging in mammalian heterologous systems. Since TMC channels are conserved across taxa, genetic studies of TMC channels in model organisms such as C. elegans, Drosophila, and zebrafish may provide us critical information on the physiological function and regulation of TMCs. Here, we present a comparative overview on the diverse functions of TMC channels in different species.


Assuntos
Canais Iônicos/metabolismo , Animais , Perda Auditiva/genética , Perda Auditiva/patologia , Humanos , Canais Iônicos/química , Canais Iônicos/genética , Mecanotransdução Celular , Mutação de Sentido Incorreto , Neurônios/metabolismo , Propriocepção , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo
12.
Pflugers Arch ; 471(2): 357-363, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30206705

RESUMO

Serotonin plays an essential role in both the invertebrate and vertebrate nervous systems. ADF, an amphid neuron with dual ciliated sensory endings, is considered to be the only serotonergic sensory neuron in the hermaphroditic Caenorhabditis elegans. This neuron is known to be involved in a range of behaviors including pharyngeal pumping, dauer formation, sensory transduction, and memory. However, whether ADF neuron is directly activated by environmental cues and how it processes these information remains unknown. In this study, we found that ADF neuron responds reliably to noxious stimuli such as repulsive odors, copper, sodium dodecyl sulfonate (SDS), and mechanical perturbation. This response is mediated by cell-autonomous and non-cell autonomous mechanisms. Furthermore, we show that ADF can modulate avoidance behaviors by inhibiting ASH, an amphid neuron with single ciliated ending. This work greatly furthers our understanding of 5-HT's contributions to sensory information perception, processing, and the resulting behavioral responses.


Assuntos
Aprendizagem da Esquiva/fisiologia , Caenorhabditis elegans/fisiologia , Células Receptoras Sensoriais/fisiologia , Neurônios Serotoninérgicos/fisiologia , Animais , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Cobre/metabolismo , Sistema Nervoso/metabolismo , Sistema Nervoso/fisiopatologia , Células Receptoras Sensoriais/metabolismo , Neurônios Serotoninérgicos/metabolismo , Serotonina/metabolismo , Transdução de Sinais/fisiologia , Dodecilsulfato de Sódio/metabolismo
13.
BMC Psychiatry ; 18(1): 339, 2018 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-30340472

RESUMO

BACKGROUND: Studies have confirmed that the thalamus and the primary somatosensory cortex (SI) are associated with cognitive function. These two brain regions are closely related in structure and function. The interactions between SI and the thalamus are of crucial significance for the cognitive process. Patients with major depressive disorder (MDD) have significant cognitive impairment. Based on these observations, we used resting-state functional magnetic resonance imaging (rs-fMRI) to investigate whether there is an abnormality in the SI-thalamic functional connection in MDD. Furthermore, we explored the clinical symptoms related to this abnormality. METHODS: We included 31 patients with first-episode major depressive disorder and 28 age-, gender-, and education-matched healthy controls (HC). The SI-thalamic functional connectivity was compared between the MDD and HC groups. The correlation analyses were performed between areas with abnormal connectivity and clinical characteristics. RESULTS: Compared with healthy subjects, the MDD patients had enhanced functional connectivity between the thalamus and SI (p < 0.05, corrected). Brain areas with significantly different levels of connectivity had a negative correlation with the Assessment of Neuropsychological Status total score (r = - 0.383, p = 0.033), delayed memory score (r = - 0.376, p = 0.037) and two-digit continuous operation test score (r = - 0.369, p = 0.041) in MDD patients. CONCLUSIONS: These results demonstrate that SI-thalamic functional connectivity is abnormal and associated with the core clinical symptoms in MDD. The SI-thalamic functional connectivity functions as a neurobiological feature and potential biomarker for MDD.


Assuntos
Transtorno Depressivo Maior/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/fisiopatologia , Córtex Somatossensorial/fisiopatologia , Tálamo/fisiopatologia , Adulto , Estudos de Casos e Controles , Transtorno Depressivo Maior/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Rede Nervosa/diagnóstico por imagem , Córtex Somatossensorial/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Adulto Jovem
14.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 47(3): 307-312, 2018 05 25.
Artigo em Zh | MEDLINE | ID: mdl-30226334

RESUMO

Olfactory adaptation is an important physiological function of animals, which can protect their own neurons from overstimulation, and be better to deal with all kinds of stimuli in the surrounding environment. In this article, we discuss the neuronal basis of olfactory adaptation in Caenorhabditis elegans. Up to now, several intracellular regulatory factors have been discovered to be associated with olfactory adaptation in Caenorhabditis elegans, including cyclic guanosine monophosphate (cGMP) signaling in the olfactory neurons AWC, OSM-9 in transient receptor potential vanilloid (TRPV) channel, arrestin ARR-1, diglyceride (DAG) pathway in G protein signaling pathways, etc. However, the neural circuits of the olfactory adaptation remains largely unknown. This paper reviews molecular and cell biological mechanism of olfactory adaptation in Caenorhabditis elegans, so as to provide reference for studies on olfactory sensation in advanced animals.


Assuntos
Adaptação Fisiológica , Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Adaptação Fisiológica/genética , Animais , Proteínas de Caenorhabditis elegans/metabolismo , Células Receptoras Sensoriais/fisiologia
15.
J Cell Physiol ; 232(11): 2946-2956, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28121014

RESUMO

Acting in the interfaces between environment and membrane compartments, membrane ion channels, and receptors transduce various physical and chemical cues into downstream signaling events. Not surprisingly, these membrane proteins play essential roles in a wide range of cellular processes such as sensory perception, synaptic transmission, cellular growth and development, fate determination, and apoptosis. However, except insulin and insulin-like growth factor receptors, the functions of membrane receptors in animal lifespan modulation have not been well appreciated. On the other hand, although ion channels are popular therapeutic targets for many age-related diseases, their potential roles in aging itself are largely neglected. In this review, we will discuss our current understanding of the conserved functions and mechanisms of membrane ion channels and receptors in the modulation of lifespan across multiple species including Caenorhabditis elegans, Drosophila, mouse, and human.


Assuntos
Envelhecimento/metabolismo , Membrana Celular/metabolismo , Moduladores de Transporte de Membrana/metabolismo , Receptores de Superfície Celular/metabolismo , Transdução de Sinais , Fatores Etários , Animais , Meio Ambiente , Humanos , Longevidade , Fenótipo , Receptores Proteína Tirosina Quinases/metabolismo
16.
EMBO J ; 31(6): 1379-93, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22252129

RESUMO

Oxygen influences behaviour in many organisms, with low levels (hypoxia) having devastating consequences for neuron survival. How neurons respond physiologically to counter the effects of hypoxia is not fully understood. Here, we show that hypoxia regulates the trafficking of the glutamate receptor GLR-1 in C. elegans neurons. Either hypoxia or mutations in egl-9, a prolyl hydroxylase cellular oxygen sensor, result in the internalization of GLR-1, the reduction of glutamate-activated currents, and the depression of GLR-1-mediated behaviours. Surprisingly, hypoxia-inducible factor (HIF)-1, the canonical substrate of EGL-9, is not required for this effect. Instead, EGL-9 interacts with the Mint orthologue LIN-10, a mediator of GLR-1 membrane recycling, to promote LIN-10 subcellular localization in an oxygen-dependent manner. The observed effects of hypoxia and egl-9 mutations require the activity of the proline-directed CDK-5 kinase and the CDK-5 phosphorylation sites on LIN-10, suggesting that EGL-9 and CDK-5 compete in an oxygen-dependent manner to regulate LIN-10 activity and thus GLR-1 trafficking. Our findings demonstrate a novel mechanism by which neurons sense and respond to hypoxia.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Hipóxia Celular/fisiologia , Neurônios/metabolismo , Receptores de AMPA/metabolismo , Receptores de Glutamato/metabolismo , Fatores de Transcrição/metabolismo , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Quinases Ciclina-Dependentes/metabolismo , Proteínas de Membrana/metabolismo , Mutação , Oxigênio/metabolismo , Fosforilação , Isoformas de Proteínas , Transporte Proteico/genética , Transporte Proteico/fisiologia
19.
ScientificWorldJournal ; 2014: 525387, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24711729

RESUMO

Biometrics plays an important role in authentication applications since they are strongly linked to holders. With an increasing growth of e-commerce and e-government, one can expect that biometric-based authentication systems are possibly deployed over the open networks in the near future. However, due to its openness, the Internet poses a great challenge to the security and privacy of biometric authentication. Biometric data cannot be revoked, so it is of paramount importance that biometric data should be handled in a secure way. In this paper we present a scheme achieving privacy-preserving fingerprint authentication between two parties, in which fingerprint minutiae matching algorithm is completed in the encrypted domain. To improve the efficiency, we exploit homomorphic encryption as well as garbled circuits to design the protocol. Our goal is to provide protection for the security of template in storage and data privacy of two parties in transaction. The experimental results show that the proposed authentication protocol runs efficiently. Therefore, the protocol can run over open networks and help to alleviate the concerns on security and privacy of biometric applications over the open networks.


Assuntos
Identificação Biométrica , Modelos Teóricos , Privacidade , Algoritmos , Humanos
20.
Neuron ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38986620

RESUMO

Transmembrane channel-like (TMC) proteins are expressed throughout the animal kingdom and are thought to encode components of ion channels. Mammals express eight TMCs (mTMC1-8), two of which (mTMC1 and mTMC2) are subunits of mechanotransduction channels. C. elegans expresses two TMCs (TMC-1 and TMC-2), which mediate mechanosensation, egg laying, and alkaline sensing. The mechanisms by which nematode TMCs contribute to such diverse physiological processes and their functional relationship to mammalian mTMCs is unclear. Here, we show that association with accessory proteins tunes nematode TMC-1 to divergent sensory functions. In addition, distinct TMC-1 domains enable touch and alkaline sensing. Strikingly, these domains are segregated in mammals between mTMC1 and mTMC3. Consistent with these findings, mammalian mTMC1 can mediate mechanosensation in nematodes, while mTMC3 can mediate alkaline sensation. We conclude that sequence diversification and association with accessory proteins has led to the emergence of TMC protein complexes with diverse properties and physiological functions.

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