Spo0M: structure and function beyond regulation of sporulation.

In this mini-review, we present a perspective on the recent findings relating Spo0M structure and function that will stimulate and guide further studies in the characterization of this interesting protein. Cell division and sporulation constitute two of the best studied processes in the model organism Bacillus subtilis; however, there are many missing pieces in the giant regulatory puzzle that governs the independent and shared networks between them. Spo0M is a little studied protein that has been related to both, cell division and sporulation, but its biochemical function and its direct interactions have not been yet defined. Structural analysis of Spo0M revealed the presence of an arrestin-like domain and an FP domain (a dimerization domain present in proteasome elements), motifs more commonly found in eukaryotic proteins. The aim of this perspective is to present open questions regarding the functional and structural features of Spo0M that make this protein a good candidate for the ancestor of arrestins in bacteria and an important element in developmental and differentiation processes of Bacillus subtilis.

El significado del capital social "individual" en diabéticos receptores de cuidado en un contexto urbano colombiano / The meaning of "individual" social capital for diabetics receiving care in a Colombian city / O significado do capital social "individual" em diabéticos que precisam de cuidados dentro de um contexto urbano colombiano

Comprender el significado del capital social de la diabetes tipo 2 según género, dentro un contexto urbano colombiano. Investigación cualitativa del interaccionismo simbólico. 25 mujeres y 16 hombres, diabéticos, familiares, vecinos y personal asistencial participaron en seis grupos focales. Emergieron 850 códigos que se integraron en un set de 142 códigos de códigos para el ego, el alter y alter ego. Tres categorías y veinte subcategorías fueron identificadas para el diseño del "paradigma de la codificación". El significado no es igual para hombres y mujeres. Los vínculos sociales de las redes sociales, creados cotidianamente por la confianza y la solidaridad para el cuidado, son valorados de manera diferente, debido a experiencias y hechos sociales resultantes de la autoconfianza, la autoeficacia para el apoyo social principalmente y, la autoestima frente al manejo y control de la enfermedad. Los recursos sociales de un individuo son reificados para el manejo y cuidado de la enfermedad como estrategia para disminuir las inequidades en salud.

The aim of this study was to understand the meaning of social capital in relation to type 2 diabetes according to gender, within an urban setting in Colombia, based on a qualitative design for symbolic interactionism. Twenty-four women and 16 men with diabetes, family members, and healthcare personnel participated in six focus groups. A total of 850 codes emerged that comprised a set of 142 codes for ego, alter, and alter ego. Three categories and 20 subcategories were identified for the "coding paradigm design". The meaning differed between men and women. Social ties in social networks, created daily through trust and solidarity for care, were valued differently due to the social experiences and events resulting from self-confidence, self-efficacy for social support, and mainly self-esteem vis-à-vis management and control of the disease. An individual's social resources are reified for the management and care of the disease as a strategy to mitigate health inequalities. .

Compreender o significado do capital social, diabetes tipo 2 por sexo, um contexto urbano da Colômbia. pesquisa qualitativa do interacionismo simbólico. 25 mulheres e 16 homens, diabéticos, familiares, vizinhos e cuidadores participaram seis grupos focais. 850 códigos se que foram integrados em um conjunto de 142 codes para o ego, o alter e alter ego. Três categorias e vinte subcategorias foram identificados para o projeto de "codificação de paradigma". O significado não é o mesmo para homens e mulheres. Laços sociais das redes sociais criadas diariamente pela confiança e solidariedade são valorizados cuidado diferente, porque as experiências sociais e fatos resultantes da auto-confiança, auto-eficácia e de apoio social, principalmente, auto-gestão e controle em relação a doença. Os recursos sociais de um indivíduo são reificadas para a gestão o cuidado da doença como uma estratégia para reduzir as desigualdades na saúde.

Morphine prevents lipopolysaccharide-induced TNF secretion in mast cells blocking IκB kinase activation and SNAP-23 phosphorylation: correlation with the formation of a ß-arrestin/TRAF6 complex.

We have previously shown that morphine pretreatment inhibits mast cell-dependent TNF production after LPS injection in the murine peritoneal cavity. In this study, we used bone marrow-derived mast cells (BMMCs) to investigate the molecular mechanisms of that inhibition. We found that morphine prevented LPS-induced TNF secretion in these cells. The observed inhibition was not due to morphine-induced TLR4 internalization and it was related to the blockage of preformed TNF secretion. LPS-induced TNF exocytosis in BMMCs was dependent on tetanus toxin-insensitive vesicle-associated membrane proteins and calcium mobilization, as well as PI3K, MAPK, and IκB kinase (IKK) activation. TNF secretion was also associated to the phosphorylation of synaptosomal-associated protein 23 (SNAP-23), which was found forming a complex with IKK in LPS-activated BMMCs. Morphine pretreatment prevented TLR4-dependent ERK and IKK phosphorylation. Analyzing the signaling events upstream of IKK activation, we found diminished TGF-ß-activated kinase 1 (TAK1) phosphorylation and TNFR-associated factor (TRAF) 6 ubiquitination in BMMCs pretreated with morphine and stimulated with LPS. Morphine pretreatment provoked a marked increase in the formation of a molecular complex composed of TRAF6 and ß-arrestin-2. Naloxone and a combination of µ and δ opioid receptor antagonists prevented morphine inhibitory actions. In conclusion, our results show that activation of µ and δ opioid receptors with morphine suppresses TLR4-induced TNF release in mast cells, preventing the IKK-dependent phosphorylation of SNAP-23, which is necessary for TNF exocytosis, and this inhibition correlates with the formation of a ß-arrestin-2/TRAF6 complex. To our knowledge, these findings constitute the first evidence of molecular crosstalk between opioid receptors and the TLR4 signal transduction system in mast cells.

B-Raf and CRHR1 internalization mediate biphasic ERK1/2 activation by CRH in hippocampal HT22 Cells.

CRH is a key regulator of neuroendocrine, autonomic, and behavioral response to stress. CRH-stimulated CRH receptor 1 (CRHR1) activates ERK1/2 depending on intracellular context. In a previous work, we demonstrated that CRH activates ERK1/2 in limbic areas of the mouse brain (hippocampus and basolateral amygdala). ERK1/2 is an essential mediator of hippocampal physiological processes including emotional behavior, synaptic plasticity, learning, and memory. To elucidate the molecular mechanisms by which CRH activates ERK1/2 in hippocampal neurons, we used the mouse hippocampal cell line HT22. We document for the first time that ERK1/2 activation in response to CRH is biphasic, involving a first cAMP- and B-Raf-dependent early phase and a second phase that critically depends on CRHR1 internalization and ß-arrestin2. By means of mass-spectrometry-based screening, we identified B-Raf-associated proteins that coimmunoprecipitate with endogenous B-Raf after CRHR1 activation. Using molecular and pharmacological tools, the functional impact of selected B-Raf partners in CRH-dependent ERK1/2 activation was dissected. These results indicate that 14-3-3 proteins, protein kinase A, and Rap1, are essential for early CRH-induced ERK1/2 activation, whereas dynamin and vimentin are required for the CRHR1 internalization-dependent phase. Both phases of ERK1/2 activation depend on calcium influx and are affected by calcium/calmodulin-dependent protein kinase II inactivation. Thus, this report describes the dynamics and biphasic nature of ERK1/2 activation downstream neuronal CRHR1 and identifies several new critical components of the CRHR1 signaling machinery that selectively controls the early and late phases of ERK1/2 activation, thus providing new potential therapeutic targets for stress-related disorders.

Normal testicular function without detectable follicle-stimulating hormone. A novel mutation in the follicle-stimulating hormone receptor gene leading to apparent constitutive activity and impaired agonist-induced desensitization and internalization.

Activating mutations in the follicle-stimulating hormone (FSH) receptor (FSHR) gene are rarely detected due to the absence of a clearly defined phenotype, particularly in men. We here report the biochemical features of a novel mutation in the first extracellular loop of the FSHR. The mutation (N431I) was detected in an asymptomatic man exhibiting normal spermatogenesis, suppressed serum FSH, and normal or elevated levels of biochemical markers of FSH action. Employing different experimental strategies on HEK-293 cells transiently expressing the N431I FSHR mutant, we found that the mutation led to decreased cell surface plasma membrane expression of the receptor protein, but conferred a low level of constitutive activity associated with markedly altered agonist-stimulated desensitization and internalization. These latter features may contribute and/or amplify the persistent activation of the receptor in both absence and presence of agonist and provide new insights into opportunities for adjuvant therapies based on disruption of these processes.

Vasopressin up-regulates the expression of growth-related immediate-early genes via two distinct EGF receptor transactivation pathways.

Activation of V(1a) receptor triggers the expression of growth-related immediate-early genes (IEGs), including c-Fos and Egr-1. We found that pre-treatment of rat vascular smooth muscle A-10 cell line with the EGF receptor inhibitor AG1478 or the over-expression of an EGFR dominant negative mutant (HEBCD533) blocked the vasopressin-induced expression of IEGs, suggesting that activation of these early genes mediated by V(1a) receptor is via transactivation of the EGF receptor. Importantly, the inhibition of the metalloproteinases, which catalyzed the shedding of the EGF receptor agonist HB-EGF, selectively blocked the vasopressin-induced expression c-Fos. On the other hand, the inhibition of c-Src selectively blocked the vasopressin-induced expression of Egr-1. Interestingly, in contrast to the expression of c-Fos, the expression of Egr-1 was mediated via the Ras/MEK/MAPK-dependent signalling pathway. Vasopressin-triggered expression of both genes required the release of intracellular calcium, activation of PKC and beta-arrestin 2. These findings demonstrated that vasopressin up-regulated the expression of c-Fos and Erg-1 via transactivation of two distinct EGF receptor-dependent signalling pathways.