Dominguezcohen6832
53, 95% CI 1.01 to 2.32) and frailty (adjusted OR 3.52, 95% CI 1.97 to 6.29), relative to non-frailty.
Exiting working life early and continuing to be occupationally active until age 70 years and older were both associated with increased risk of frailty among the men. Promotion of longer work careers could, however, promote healthier ageing, as the lowest prevalence of frailty was observed in former business executives who retired at ages 66-67 years.
Exiting working life early and continuing to be occupationally active until age 70 years and older were both associated with increased risk of frailty among the men. Promotion of longer work careers could, however, promote healthier ageing, as the lowest prevalence of frailty was observed in former business executives who retired at ages 66-67 years.Little is known about the functions of Group II metabotropic glutamate receptors (mGluRs2/3) in the inferior colliculus (IC), a midbrain structure that is a major integration region of the central auditory system. We investigated how these receptors modulate sound-evoked and spontaneous firing in the mouse IC in vivo We first performed immunostaining and tested hearing thresholds to validate vesicular GABA transporter (VGAT)-ChR2 transgenic mice on a mixed CBA/CaJ x C57BL/6J genetic background. Transgenic animals allowed for optogenetic cell-type identification. Extracellular single neuron recordings were obtained before and after pharmacological mGluR2/3 activation. We observed increased sound-evoked firing, as assessed by the rate-level functions (RLFs), in a subset of both GABAergic and non-GABAergic IC neurons following mGluR2/3 pharmacological activation. These neurons also displayed elevated spontaneous excitability and were distributed throughout the IC area tested, suggesting a widespread mGluR2/3 distribution in the mouse IC.The p53 tumor suppressor protein is a potent activator of proliferative arrest and cell death. In normal cells, this pathway is restrained by p53 protein degradation mediated by the E3-ubiquitin ligase activity of MDM2. Oncogenic stress releases p53 from MDM2 control, so activating the p53 response. However, many tumors that retain wild-type p53 inappropriately maintain the MDM2-p53 regulatory loop in order to continuously suppress p53 activity. Valaciclovir We have shown previously that single point mutations in the human MDM2 RING finger domain prevent the interaction of MDM2 with the E2/ubiquitin complex, resulting in the loss of MDM2's E3 activity without preventing p53 binding. Here, we show that an analogous mouse MDM2 mutant (MDM2 I438K) restrains p53 sufficiently for normal growth but exhibits an enhanced stress response in vitro. In vivo, constitutive expression of MDM2 I438K leads to embryonic lethality that is rescued by p53 deletion, suggesting MDM2 I438K is not able to adequately control p53 function through development. However, the switch to I438K expression is tolerated in adult mice, sparing normal cells but allowing for an enhanced p53 response to DNA damage. Viewed as a proof of principle model for therapeutic development, our findings support an approach that would inhibit MDM2 E3 activity without preventing MDM2/p53 binding as a promising avenue for development of compounds to activate p53 in tumors with reduced on-target toxicities.During developmental progression the genomes of immune cells undergo large-scale changes in chromatin folding. However, insights into signaling pathways and epigenetic control of nuclear architecture remain rudimentary. Here, we found that in activated neutrophils calcium influx rapidly recruited the cohesin-loading factor NIPBL to thousands of active enhancers and promoters to dictate widespread changes in compartment segregation. NIPBL recruitment to enhancers and promoters occurred with distinct kinetics. The induction of NIPBL-binding was coordinate with increased P300, BRG1 and RNA polymerase II occupancy. NIPBL-bound enhancers were associated with NFAT, PU.1, and CEBP cis elements, whereas NIPBL-bound promoters were enriched for GC-rich DNA sequences. Using an acute degradation system, we found that the histone acetyltransferases P300 and CBP maintained H3K27ac abundance and facilitated NIPBL occupancy at enhancers and that active transcriptional elongation is essential to maintain H3K27ac abundance. Chromatin remodelers, containing either of the mutually exclusive BRG1 and BRM ATPases, promoted NIPBL recruitment at active enhancers. Conversely, at active promoters, depletion of BRG1 and BRM showed minimal effect on NIPBL occupancy. Finally, we found that calcium signaling in both primary innate and adaptive immune cells swiftly induced NIPBL occupancy. Collectively, these data reveal how transcriptional regulators, histone acetyltransferases, chromatin remodelers, and transcription elongation promote NIPBL occupancy at active enhancers while the induction of NIPLB occupancy at promoters is primarily associated with GC-rich DNA sequences.How homeodomain proteins gain sufficient specificity to control different cell fates has been a long-standing problem in developmental biology. The conserved Gsx homeodomain proteins regulate specific aspects of neural development in animals from flies to mammals, and yet they belong to a large transcription factor family that bind nearly identical DNA sequences in vitro. Here, we show that the mouse and fly Gsx factors unexpectedly gain DNA binding specificity by forming cooperative homodimers on precisely spaced and oriented DNA sites. High-resolution genomic binding assays revealed that Gsx2 binds both monomer and homodimer sites in the developing mouse ventral telencephalon. Importantly, reporter assays showed that Gsx2 mediates opposing outcomes in a DNA binding site-dependent manner Monomer Gsx2 binding represses transcription, whereas homodimer binding stimulates gene expression. In Drosophila, the Gsx homolog, Ind, similarly represses or stimulates transcription in a site-dependent manner via an autoregulatory enhancer containing a combination of monomer and homodimer sites. Integrating these findings, we test a model showing how the homodimer to monomer site ratio and the Gsx protein levels defines gene up-regulation versus down-regulation. Altogether, these data serve as a new paradigm for how cooperative homeodomain transcription factor binding can increase target specificity and alter regulatory outcomes.