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Crystal structures of FolM alternative dihydrofolate reductase 1 from Brucella suis and Brucella canis reveal prototypical NADPH-dependent short-chain reductases with structural similarity to protozoan pteridine reductases that are potential drug targets., Members of the bacterial genus Brucella cause brucellosis, a zoonotic disease that affects both livestock and wildlife. Brucella are category B infectious agents that can be aerosolized for biological warfare. As part of the structural genomics studies at the Seattle Structural Genomics Center for Infectious Disease (SSGCID), FolM alternative dihydrofolate reductases 1 from Brucella suis and Brucella canis were produced and their structures are reported. The enzymes share ∼95% sequence identity but have less than 33% sequence identity to other homologues with known structure. The structures are prototypical NADPH-dependent short-chain reductases that share their highest tertiary-structural similarity with protozoan pteridine reductases, which are being investigated for rational therapeutic development.

PurposeAgainst the backdrop of a competitive hiring market and historically high rates of quitting, the current research examines a factor that could support talent retention in organizations: employees’ feelings of connectedness to their top executives. The authors examined the relationship between workers’ feelings of executive connectedness and job attitudes relative to other antecedents and its predictive power for quitting over and above manager and team connectedness.Design/methodology/approachIn Study 1, the authors measured the relative predictive power of executive connectedness, along with 14 other antecedents, for the outcome of job attitudes in ten samples totaling over 70,000 observations, including two longitudinal samples. In Study 2, the authors used path analysis to test the relationship between executive connectedness and actual quitting, controlling for workers’ feelings of connectedness to their manager and teammates, in two (related) longitudinal samples.FindingsExecutive connectedness was robustly related to concurrent and future job attitudes, and it outranked manager variables in all samples. Executive connectedness predicted quitting, even when controlling for manager and team connectedness; this effect was mediated by job attitudes in one of two samples.Practical implicationsExecutive connectedness could be an underutilized resource for understanding and possibly improving employee attitudes and retention. Executives should not delegate all responsibility for employee attitudes and retention to managers.Originality/valueThis research is to the authors' knowledge the first to systematically test the unique predictive validity of employees’ feelings of connectedness to executives for important outcomes. The results suggest that executive connectedness may be an important factor in employees’ workplace experience.

Osteopontin (OPN) also known by its official gene designation secreted phosphoprotein-1 (SPP1) is a fascinating, multifunctional protein expressed in a number of cell types that functions not only in intercellular communication, but also in the extracellular matrix (ECM). OPN/SPP1 possesses cytokine, chemokine, and signal transduction functions by virtue of modular structural motifs that provide interaction surfaces for integrins and CD44-variant receptors. In humans, there are three experimentally verified splice variants of OPN/SPP1 and CD44's ten exons are also alternatively spiced in a cell/tissue-specific manner, although very little is known about how this is regulated in the central nervous system (CNS). Post-translational modifications of phosphorylation, glycosylation, and localized cleavage by specific proteases in the cells and tissues where OPN/SPP1 functions, provides additional layers of specificity. However, the former make elucidating the exact molecular mechanisms of OPN/SPP1 function more complex. Flexibility in OPN/SPP1 structure and its engagement with integrins having the ability to transmit signals in inside-out and outside-in direction, is likely why OPN/SPP1 can serve as an early detector of inflammation and ongoing tissue damage in response to cancer, stroke, traumatic brain injury, pathogenic infection, and neurodegeneration, processes that impair tissue homeostasis. This review will focus on what is currently known about OPN/SPP1 function in the brain.

Purpose: Despite extensive research, an effective and safe treatment for diffuse intrinsic pontine glioma (DIPG) has not been established. In this study, we investigate the therapeutic potential of combination therapy with histone deacetylase (HDAC) and carbonic anhydrase 9 (CA9) inhibitors against DIPG.Methods: We used RNA sequencing data from DIPG patient samples to evaluate the expression of the carbonic anhydrase family and the activity of the hypoxia signaling pathway. Next, we performed a synergy screen using CA9 inhibitor SLC-0111 and the HDAC inhibitors panobinostat, vorinostat, entinostat, and pyroxamide. We selected the SLC-0111/HDACi combination showing the highest synergy, and its effects on cell proliferation, invasion, and migration were evaluated. We also measured changes in histone acetylation, apoptosis, cell cycle, and intracellular pH.Results: CA9 was significantly upregulated in human DIPG samples. Furthermore, pathways downstream of CA9 were found to be activated when compared to normal brain tissue. The synergy screen revealed that the combination of SLC-0111 and pyroxamide was most effective at inhibiting DIPG cell proliferation. Furthermore, this combination reduced cell migration and invasion potential while enhancing histone acetylation with subsequent reduction of cell population in S Phase. Finally, the SLC-0111 and pyroxamide combination showed greater reduction of intracellular pH as compared to each agent alone.Conclusion: Our in vitro data suggest that the combination of SLC-0111 and pyroxamide shows promise in the treatment of experimental DIPG. Based on these findings, further investigation of this combination therapy in preclinical models is warranted.

RationaleSevere viral respiratory infections are often characterised by extensive myeloid cell infiltration and activation and persistent lung tissue injury. However, the immunological mechanisms driving excessive inflammation in the lung remain poorly understood.ObjectivesTo identify the mechanisms that drive immune cell recruitment in the lung during viral respiratory infections and identify novel drug targets to reduce inflammation and disease severity.MethodsPreclinical murine models of influenza A virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.ResultsOxidised cholesterols and the oxysterol-sensing receptor GPR183 were identified as drivers of monocyte/macrophage infiltration to the lung during influenza A virus (IAV) and SARS-CoV-2 infection. Both IAV and SARS-CoV-2 infection upregulated the enzymes cholesterol 25-hydroxylase (CH25H) and cytochrome P450 family 7 subfamily member B1 (CYP7B1) in the lung, resulting in local production of the oxidised cholesterols 25-hydroxycholesterol (25-OHC) and 7α,25-dihydroxycholesterol (7α,25-OHC). Loss-of-function mutation of Gpr183 or treatment with a GPR183 antagonist reduced macrophage infiltration and inflammatory cytokine production in the lungs of IAV- or SARS-CoV-2-infected mice. The GPR183 antagonist significantly attenuated the severity of SARS-CoV-2 infection and viral loads. Analysis of single-cell RNA-sequencing data on bronchoalveolar lavage samples from healthy controls and COVID-19 patients with moderate and severe disease revealed thatCH25H,CYP7B1andGPR183are significantly upregulated in macrophages during COVID-19.ConclusionThis study demonstrates that oxysterols drive inflammation in the lungviaGPR183 and provides the first preclinical evidence for the therapeutic benefit of targeting GPR183 during severe viral respiratory infections.