Gi- and Gs-coupled GPCRs show different modes of G-protein binding.

More than two decades ago, the activation mechanism for the membrane-bound photoreceptor and prototypical G protein-coupled receptor (GPCR) rhodopsin was uncovered. Upon light-induced changes in ligand-receptor interaction, movement of specific transmembrane helices within the receptor opens a crevice at the cytoplasmic surface, allowing for coupling of heterotrimeric guanine nucleotide-binding proteins (G proteins). The general features of this activation mechanism are conserved across the GPCR superfamily. Nevertheless, GPCRs have selectivity for distinct G-protein family members, but the mechanism of selectivity remains elusive. Structures of GPCRs in complex with the stimulatory G protein, Gs, and an accessory nanobody to stabilize the complex have been reported, providing information on the intermolecular interactions. However, to reveal the structural selectivity filters, it will be necessary to determine GPCR-G protein structures involving other G-protein subtypes. In addition, it is important to obtain structures in the absence of a nanobody that may influence the structure. Here, we present a model for a rhodopsin-G protein complex derived from intermolecular distance constraints between the activated receptor and the inhibitory G protein, Gi, using electron paramagnetic resonance spectroscopy and spin-labeling methodologies. Molecular dynamics simulations demonstrated the overall stability of the modeled complex. In the rhodopsin-Gi complex, Gi engages rhodopsin in a manner distinct from previous GPCR-Gs structures, providing insight into specificity determinants

Tools for Inclusion- Career Center Success: Addressing Job-Seeker Benefit Concerns

A primary barrier to employment of individuals with disabilities is concerns over the impact of earnings from employment on public benefits. These benefits include cash benefits from Social Security, health coverage via Medicaid and Medicare, SNAP (food stamps), subsidized housing, and others. The Social Security Administration funds Work Incentive Planning and Assistance (WIPA) programs to provide benefits counseling to individuals with disabilities. The purpose of WIPA services is to address any questions or concerns Social Security beneficiaries have regarding the impact of earnings on benefits, and to encourage them to pursue employment. However, the availability of WIPA services is limited. To expand benefits assistance, DEI grant funds enhanced access to WIPA services from BenePlan at UMass Medical School. CWICs (Community Work Incentive Counselors) from BenePlan provided benefits counseling to DEI participants who were Social Security beneficiaries. (For the purposes of this publication, we will refer to CWICs as “benefit specialists.”) This brief discusses the impact of benefits counseling, including the enhanced benefits counseling funded by DEI, on individual’s efforts to become successfully employed

Crystal structure of rhodopsin bound to arrestin by femtosecond X-ray laser.

G-protein-coupled receptors (GPCRs) signal primarily through G proteins or arrestins. Arrestin binding to GPCRs blocks G protein interaction and redirects signalling to numerous G-protein-independent pathways. Here we report the crystal structure of a constitutively active form of human rhodopsin bound to a pre-activated form of the mouse visual arrestin, determined by serial femtosecond X-ray laser crystallography. Together with extensive biochemical and mutagenesis data, the structure reveals an overall architecture of the rhodopsin-arrestin assembly in which rhodopsin uses distinct structural elements, including transmembrane helix 7 and helix 8, to recruit arrestin. Correspondingly, arrestin adopts the pre-activated conformation, with a ∼20° rotation between the amino and carboxy domains, which opens up a cleft in arrestin to accommodate a short helix formed by the second intracellular loop of rhodopsin. This structure provides a basis for understanding GPCR-mediated arrestin-biased signalling and demonstrates the power of X-ray lasers for advancing the frontiers of structural biology

Enfermedades crónicas

Adherencia al tratamiento farmacológico y relación con el control metabólico en pacientes con DM2Aluminio en pacientes con terapia de reemplazo renal crónico con hemodiálisis en Bogotá, ColombiaAmputación de extremidades inferiores: ¿están aumentando las tasas?Consumo de edulcorantes artificiales en jóvenes universitariosCómo crecen niños normales de 2 años que son sobrepeso a los 7 añosDiagnóstico con enfoque territorial de salud cardiovascular en la Región MetropolitanaEfecto a corto plazo de una intervención con ejercicio físico, en niños con sobrepesoEfectos de la cirugía bariátrica en pacientes con síndrome metabólico e IMC < 35 KG/M2Encuesta mundial de tabaquismo en estudiantes de profesiones de saludEnfermedades crónicas no transmisibles: Consecuencias sociales-sanitarias de comunidades rurales en ChileEpidemiología de las muertes hospitalarias por patologías relacionadas a muerte encefálica, Chile 2003-2007Estado nutricional y conductas alimentarias en adolescentes de 4º medio de la Región de CoquimboEstudio de calidad de vida en una muestra del plan piloto para hepatitis CEvaluación del proceso asistencial y de resultados de salud del GES de diabetes mellitus 2Factores de riesgo cardiovascular en población universitaria de la Facsal, universidad de TarapacáImplicancias psicosociales en la génesis, evolución y tratamiento de pacientes con hipertensión arterial esencialInfarto agudo al miocardio (IAM): Realidad en el Hospital de Puerto Natales, 2009-2010Introducción de nuevas TIC y mejoría de la asistencia a un programa de saludNiños obesos atendidos en el Cesfam de Puerto Natales y su entorno familiarPerfil de la mortalidad por cáncer de cuello uterino en Río de JaneiroPerfil del paciente primo-consultante del Programa de Salud Cardiovascular, Consultorio Cordillera Andina, Los AndesPrevalencia de automedicación en mujeres beneficiarias del Hospital Comunitario de Til-TiPrevalencia de caries en población preescolar y su relación con malnutrición por excesoPrevalencia de retinopatía diabética en comunas dependientes del Servicio de Salud Metropolitano Occidente (SSMOC)Problemas de adherencia farmacológica antihipertensiva en población mapuche: Un estudio cualitativoRol biológico de los antioxidantes innatos en pacientes portadores de VIH/SidaSobrepeso en empleados de un restaurante de una universidad pública del estado de São Paul

An efficient strategy for evaluating new non-invasive screening tests for colorectal cancer: the guiding principles

Objective: New screening tests for colorectal cancer (CRC) are rapidly emerging. Conducting trials with mortality reduction as the end point supporting their adoption is challenging. We re-examined the principles underlying evaluation of new non-invasive tests in view of technological developments and identification of new biomarkers. Design: A formal consensus approach involving a multidisciplinary expert panel revised eight previously established principles. Results: Twelve newly stated principles emerged. Effectiveness of a new test can be evaluated by comparison with a proven comparator non-invasive test. The faecal immunochemical test is now considered the appropriate comparator, while colonoscopy remains the diagnostic standard. For a new test to be able to meet differing screening goals and regulatory requirements, flexibility to adjust its positivity threshold is desirable. A rigorous and efficient four-phased approach is proposed, commencing with small studies assessing the test’s ability to discriminate between CRC and non-cancer states (phase I), followed by prospective estimation of accuracy across the continuum of neoplastic lesions in neoplasia-enriched populations (phase II). If these show promise, a provisional test positivity threshold is set before evaluation in typical screening populations. Phase III prospective studies determine single round intention-to-screen programme outcomes and confirm the test positivity threshold. Phase IV studies involve evaluation over repeated screening rounds with monitoring for missed lesions. Phases III and IV findings will provide the real-world data required to model test impact on CRC mortality and incidence. Conclusion: New non-invasive tests can be efficiently evaluated by a rigorous phased comparative approach, generating data from unbiased populations that inform predictions of their health impact

CONCEPTION ET CARACTERISATION DE BIOCAPTEURS BASES SUR L'ASSOCIATION DE RECEPTEURS ET CANAUX IONIQUES

ATP sensitive potassium channels (KATP) comprise two proteins: The sulfonylurea receptor (SUR, an ABC protein) and an inward rectifier potassium channel (Kir6.2). Upon binding of different types of effectors (nucleotides, pharmacological compounds), SUR, the regulatory subunit, modulates the gating of Kir6.2. The KATP channel links the metabolic state of the cell to its electrical excitability. Thereby, it acts as a metabolic sensor and is involved in physiological functions such as insulin secretion, cardioprotection, vascular tone control... Thus, the KATP channel constitutes a therapeutic target. In this work, we studied the effects of benzothiazine derivatives on SUR1 + Kir6.2 and SUR2A + Kir6.2. We also investigated the effects of two pesticides, amitraz and diflubenzuron on the KATP channel. To extend the concept of Ion Channel-Coupled Receptor (ICCR) initiated in the laboratory, we designed new constructs by engineering fusion between Kir6.2 and five GPCRs: the β2 adrenergic, cannabinoid 1 (CB1), dopaminergic D3, CC-chemokine (CCR2) receptors and opsin. The receptor C-ter and Kir6.2 N-ter extremities were pared to promote efficient coupling and joined covalently. The fusions were heterologously expressed in Xenopus oocytes and characterized by the two-electrode voltage clamp technique. Three ICCR β2 adrenergic-based, CB1-based and D3-based) out of five were shown to be functional. Thus, the ICCR concept is readily applicable to class A GPCRs. Besides their obvious interest in drug screening, the new ICCRs should be valuable tools to investigate the intermolecular events involved in the modulation of Kir6.2 gating and the nature of the GPCR conformational changes evoked by their ligands.Les canaux sensibles à l'ATP (KATP) résultent de l'association unique d'une protéine ABC (le récepteur des sulfonylurées, SUR) et d'un canal potassique rectifiant entrant (Kir6.x). Suite à la liaison de divers effecteurs (nucléotides, molécules pharmacologiques), SUR module l'activité de Kir6.x. Dans l'organisme, les canaux KATP lient le niveau énergétique de la cellule au potentiel membranaire. De ce fait, leur implication dans diverses fonctions physiologiques telles que la sécrétion pancréatique d'insuline ou le contrôle du tonus vasculaire en fait des cibles thérapeutiques. Ainsi, dans le cadre d'une collaboration, nous avons testé des composés (dérivés benzothiazine) sur le canal KATP. Quatre d'entre eux se sont avérés être des ouvreurs des canaux KATP. Nous avons également exploré l'effet de deux insecticides, l'amitraz et le diflubenzuron sur le canal KATP. En outre, dans une optique de généralisation du concept d'Ion Channel-Coupled Receptor (ICCR) mis au point par l'équipe, nous avons élaboré des biocapteurs reposant sur l'assemblage de récepteurs couplés aux protéines G (GPCR) et Kir6.2. Cette association, inspirée par le canal KATP, est réalisée de telle manière que la fixation d'un ligand sur le GPCR entraîne la modulation de l'activité de Kir6.2. L'ingénierie moléculaire nous a permis de fusionner Kir6.2 aux récepteurs β2 adrénergique, dopaminergique D3, cannabinoïde 1 (CB1), des CC-chimiokines 2 et à l'opsine. La méthode de double-microélectrodes nous a permis d'identifier trois ICCR fonctionnels basés sur les récepteurs β2, D3 et CB1. Ces biocapteurs présentent des applications dans le cadre du criblage haut débit, la caractérisation fonctionnelle des GPCR ou la compréhension de la régulation de l'activité de Kir6.2

CONCEPTION ET CARACTERISATION DE BIOCAPTEURS BASES SUR L'ASSOCIATION DE RECEPTEURS ET CANAUX IONIQUES

ATP sensitive potassium channels (KATP) comprise two proteins: The sulfonylurea receptor (SUR, an ABC protein) and an inward rectifier potassium channel (Kir6.2). Upon binding of different types of effectors (nucleotides, pharmacological compounds), SUR, the regulatory subunit, modulates the gating of Kir6.2. The KATP channel links the metabolic state of the cell to its electrical excitability. Thereby, it acts as a metabolic sensor and is involved in physiological functions such as insulin secretion, cardioprotection, vascular tone control... Thus, the KATP channel constitutes a therapeutic target. In this work, we studied the effects of benzothiazine derivatives on SUR1 + Kir6.2 and SUR2A + Kir6.2. We also investigated the effects of two pesticides, amitraz and diflubenzuron on the KATP channel. To extend the concept of Ion Channel-Coupled Receptor (ICCR) initiated in the laboratory, we designed new constructs by engineering fusion between Kir6.2 and five GPCRs: the β2 adrenergic, cannabinoid 1 (CB1), dopaminergic D3, CC-chemokine (CCR2) receptors and opsin. The receptor C-ter and Kir6.2 N-ter extremities were pared to promote efficient coupling and joined covalently. The fusions were heterologously expressed in Xenopus oocytes and characterized by the two-electrode voltage clamp technique. Three ICCR β2 adrenergic-based, CB1-based and D3-based) out of five were shown to be functional. Thus, the ICCR concept is readily applicable to class A GPCRs. Besides their obvious interest in drug screening, the new ICCRs should be valuable tools to investigate the intermolecular events involved in the modulation of Kir6.2 gating and the nature of the GPCR conformational changes evoked by their ligands.Les canaux sensibles à l'ATP (KATP) résultent de l'association unique d'une protéine ABC (le récepteur des sulfonylurées, SUR) et d'un canal potassique rectifiant entrant (Kir6.x). Suite à la liaison de divers effecteurs (nucléotides, molécules pharmacologiques), SUR module l'activité de Kir6.x. Dans l'organisme, les canaux KATP lient le niveau énergétique de la cellule au potentiel membranaire. De ce fait, leur implication dans diverses fonctions physiologiques telles que la sécrétion pancréatique d'insuline ou le contrôle du tonus vasculaire en fait des cibles thérapeutiques. Ainsi, dans le cadre d'une collaboration, nous avons testé des composés (dérivés benzothiazine) sur le canal KATP. Quatre d'entre eux se sont avérés être des ouvreurs des canaux KATP. Nous avons également exploré l'effet de deux insecticides, l'amitraz et le diflubenzuron sur le canal KATP. En outre, dans une optique de généralisation du concept d'Ion Channel-Coupled Receptor (ICCR) mis au point par l'équipe, nous avons élaboré des biocapteurs reposant sur l'assemblage de récepteurs couplés aux protéines G (GPCR) et Kir6.2. Cette association, inspirée par le canal KATP, est réalisée de telle manière que la fixation d'un ligand sur le GPCR entraîne la modulation de l'activité de Kir6.2. L'ingénierie moléculaire nous a permis de fusionner Kir6.2 aux récepteurs β2 adrénergique, dopaminergique D3, cannabinoïde 1 (CB1), des CC-chimiokines 2 et à l'opsine. La méthode de double-microélectrodes nous a permis d'identifier trois ICCR fonctionnels basés sur les récepteurs β2, D3 et CB1. Ces biocapteurs présentent des applications dans le cadre du criblage haut débit, la caractérisation fonctionnelle des GPCR ou la compréhension de la régulation de l'activité de Kir6.2

Conception et caractérisation de biocapteurs basés sur l'association de récepteurs et canaux ioniques

Les canaux sensibles à l'ATP (KATP) résultent de l'association unique d'une protéine ABC (le récepteur des sulfonylurées, SUR) et d'un canal potassique rectifiant entrant (Kir6.x). Suite à la liaison de divers effecteurs (nucléotides, molécules pharmacologiques), SUR module l'activité de Kir6.x. Dans l'organisme, les canaux KA TP lient le niveau énergétique de la cellule au potentiel membranaire. De ce fait, leur implication dans diverses fonctions physiologiques telles que la sécrétion pancréatique d'insuline ou le contrôle du tonus vasculaire en fait des cibles thérapeutiques. Ainsi, dans le cadre d'une collaboration, nous avons testé des composés (dérivés benzothiazine) sur le canal KATP. Quatre d'entre eux se sont avérés être des ouvreurs des canaux KATP. Nous avons également exploré l'effet de deux insecticides, l'amitraz et le diflubenzuron sur le canal KATP. En outre, dans une optique de généralisation du concept d'Ion Channel-Coupled Receptor (ICCR) mis au point par l'équipe, nous avons élaboré des biocapteurs reposant sur l'assemblage de récepteurs couplés aux protéines G (GPCR) et Kir6.2. Cette association, inspirée par le canal KATP, est réalisée de telle manière que la fixation d'un ligand sur le GPCR entraîne la modulation de l'activité de Kir6.2. L'ingénierie moléculaire nous a permis de fusionner Kir6.2 aux récepteurs t3J. adrénergique, dopaminergique D3, cannabinoïde 1 (CBl), des CC-chimiokines 2 et à l'opsine. La méthode de double-microélectrodes nous a permis d'identifier trois ICCR fonctionnels basés sur les récepteurs t3J., D3 et CBl. Ce~ biocapteurs présentent des applications dans le cadre du criblage haut débit, la caractérisation fonctionnelle des GPCR Ol la compréhension de la régulation de l'activité de Kir6.2.A TP sensitive potassium channels (KA TP) comprise two proteins: The sulfonylurea receptor (SUR. an ABC protein) and an inward rectifier potassium channel (Kir6.2). Upon binding of different types of effectors (nucleotides, pharmacological compounds), SUR. the regulatory subunit, modulates the gating ofKir6.2. The KATP channel links the metabolic state of the cell to its electrical excitability. Thereby, it acts as a metabolic sensor and is involved in physiological functions such as insulin secretion, cardioprotection, vascular tone control... Thus, the KA TP channel constitutes a therapeutic target. ln this work, we studied the effects ofbenzothiazine derivatives on SURI + Kir6.2 and SUR2A + Kir6.2. We also investigated the effects oftwo pesticides, amitraz and diflubenzuron on the KATP channel. To extend the concept ofIon Channel-Coupled Receptor (ICCR) initiated in the laboratory, we designed new constructs by engineering fusion between Kir6.2 and five GPCRs: the t3J. adrenergic, cannabinoid 1 (CBl), dopaminergic D3, CC chemokine (CCR2) receptors and opsin. The receptor C-ter and Kir6.2 N-ter extremities were pared to promote efficient coupling and joined covalently. The fusions were heterologously expressed in Xenopus oocytes and characterized by the two-electrode voltage clamp technique. Three ICCR t3J. adrenergic-basecl, CBl-based and D3-based) out of five were shown to be functional. Thus, the ICCR concept is readily applicable to class A GPCRs. Besides their obvious interest in drug screening, the new ICCRs should be valuable tools to investigate the intermolecular events involved in the modulation of Kir6.2 gating and the nature of the GPCR conformational changes evoked by their ligands.GRENOBLE1-BU Sciences (384212103) / SudocSudocFranceF

Effective Case Management for Job Seekers

Case management is the most central and crucial aspect of a disability resource coordinator\u27s (DRC) role. Understanding how DRCs manage their caseload is an important step toward identifying best practices. In this brief, DRCs share some conclusions about the way case management functions in their roles