Structural Analysis of the Protein Phosphatase 1 Docking Motif: Molecular Description of Binding Specificities Identifies Interacting Proteins

SummaryThe interplay between kinases and phosphatases represents a fundamental regulatory mechanism in biological systems. Being less numerous than kinases, phosphatases increase their diversity by the acquisition of a variety of binding partners, thereby forming a large number of holoenzymes. Proteins interacting with protein phosphatase 1 (PP1) often bind via a so-called docking motif to regulate its enzymatic activity, substrate specificity, and subcellular localization. Here, we systematically determined structural elements that mediate the binding specificity of PP1 interacting proteins, and propose a refined consensus sequence for high-affinity PP1 ligands. Applying this pattern to database searches, we predicted and experimentally confirmed several previously unknown PP1 interactors. Thus, the suggested PP1 docking motif enables a highly specific prediction of PP1 binding partners, thereby facilitating the genome-wide identification of PP1 interactors

Numerical investigation of turbulent-jet primary breakup using One-Dimensional Turbulence

Primary breakup to form droplets at liquid surfaces is an important fundamental process to study as it determines the initial properties of the dispersed phase, which affect mixing rates, secondary breakup, droplet collisions, and flow separation within the dispersed flow region. Primary breakup can be regarded as one of the least developed model components for simulating and predicting liquid jet breakup. However, it is of paramount importance in many technical applications, e.g. fuel injection in engines and spray painting. This paper presents a numerical investigation of primary breakup of a turbulent liquid jet in still air at standard conditions using the one-dimensional turbulence (ODT) modeling framework. ODT is a stochastic model that simulates turbulent flow evolution along a notional 1D line of sight by applying instantaneous maps to represent the effect of individual turbulent eddies on property profiles. An important feature of ODT is the resolution of all relevant scales, both temporal and spatial. The restriction to one spatial dimension in ODT permits affordable high resolution of interfacial and single-phase property gradients, which is key to capturing the local behavior of the breakup process and allows simulations at high Reynolds and Weber numbers that are currently not accessible to direct numerical simulations (DNS). This paper summarizes our extensions of the ODT model to simulate geometrically simple jet breakup problems, including representations of Rayleigh wave breakup, turbulent breakup, and shear-driven breakup. Each jet breakup simulation consists of a short temporal channel section to initialize a turbulent velocity profile at the nozzle exit followed by an adjacent jet section. The simulations are carried out for jet exit Reynolds number of 11,500, 23,000, 46,000 and 92,000 while the Weber number is varied within the range 102–107. We present results on breakup statistics including spatial locations of droplet release, droplet sizes and liquid core length. The results on primary breakup are compared to experimental results and models

Deductible imputation in administrative medical claims datasets

Objective: To validate imputation methods used to infer plan-level deductibles and determine which enrollees are in high-deductible health plans (HDHPs) in administrative claims datasets. Data sources and study setting: 2017 medical and pharmaceutical claims from OptumLabs Data Warehouse for US individuals Study design: We impute plan deductibles using four methods: (1) parametric prediction using individual-level spending; (2) parametric prediction with imputation and plan characteristics; (3) highest plan-specific mode of individual annual deductible spending; and (4) deductible spending at the 80th percentile among individuals meeting their deductible. We compare deductibles' levels and categories for imputed versus actual deductibles. Data collection/extraction methods: Not applicable. Principal findings: All methods had a positive predictive value (PPV) for determining high- versus low-deductible plans of ≥87%; negative predictive values (NPV) were lower. The method imputing plan-specific deductible spending modes was most accurate and least computationally intensive (PPV: 95%; NPV: 91%). This method also best correlated with actual deductible levels; 69% of imputed deductibles were within $250 of the true deductible. Conclusions: In the absence of plan structure data, imputing plan-specific modes of individual annual deductible spending best correlates with true deductibles and best predicts enrollees in HDHPs.</p

Culturally competent communication in Indigenous disability assessment: a qualitative study

Background: Indigenous people tend to exhibit a higher burden of disability than their non-Indigenous counterparts, and are often underserved by disability services. Engaging appropriately with Indigenous communities, families and individuals in the initial stages of disability assessment and planning is crucial in order to build trust and understanding of disability service models and ensure that Indigenous people receive support that is tailored to their needs and cultural realities. This article aims to identify key elements of culturally competent communication in Indigenous disability assessment and planning, and provide recommendations for strengthening capacity in this area. Methods: This qualitative research was designed to involve Aboriginal and Torres Strait Islander people at all stages and to reflect the views of Aboriginal and Torres Strait Islander researchers, people and families affected by disability and the community-controlled health sector. Semi-structured individual interviews were undertaken with staff implementing the National Disability Insurance Scheme (NDIS) (n = 4), NDIS participants (n = 24), disability support providers and organisational partners (n = 19) and Community Connectors (n = 8) in Queensland and the Northern Territory of Australia. Key themes derived from thematic analysis included appropriate and adequate engagement of individuals with disability and their families, the role of trusted relationships, and culturally safe and appropriate communication during planning meetings. Results: Overall, the research findings highlight that a low level of cultural competence in the initial stages of the disability assessment and planning process exacerbated participant confusion and distrust towards assessment staff and the NDIS. Given difficulties in communication, participant understanding of the NDIS was generally limited. The necessity of culturally safe and appropriate use of interpreters was stressed, as was the role of trusted individuals, including existing service providers, Community Connectors and family members in providing a solid base for participant understanding of the NDIS. Conclusions: Cultural competence in disability assessment and planning can be strengthened through multi-level engagement with the Aboriginal community-controlled sector and community leaders. Implementing mechanisms to enable the involvement of families, trusted service providers and Community Connectors can support a more meaningful understanding of individuals’ needs within their cultural context and in relation to their cultural roles

Culturally competent communication in Indigenous disability assessment: a qualitative study

Background: Indigenous people tend to exhibit a higher burden of disability than their non-Indigenous counterparts, and are often underserved by disability services. Engaging appropriately with Indigenous communities, families and individuals in the initial stages of disability assessment and planning is crucial in order to build trust and understanding of disability service models and ensure that Indigenous people receive support that is tailored to their needs and cultural realities. This article aims to identify key elements of culturally competent communication in Indigenous disability assessment and planning, and provide recommendations for strengthening capacity in this area. Methods: This qualitative research was designed to involve Aboriginal and Torres Strait Islander people at all stages and to reflect the views of Aboriginal and Torres Strait Islander researchers, people and families affected by disability and the community-controlled health sector. Semi-structured individual interviews were undertaken with staff implementing the National Disability Insurance Scheme (NDIS) (n = 4), NDIS participants (n = 24), disability support providers and organisational partners (n = 19) and Community Connectors (n = 8) in Queensland and the Northern Territory of Australia. Key themes derived from thematic analysis included appropriate and adequate engagement of individuals with disability and their families, the role of trusted relationships, and culturally safe and appropriate communication during planning meetings. Results: Overall, the research findings highlight that a low level of cultural competence in the initial stages of the disability assessment and planning process exacerbated participant confusion and distrust towards assessment staff and the NDIS. Given difficulties in communication, participant understanding of the NDIS was generally limited. The necessity of culturally safe and appropriate use of interpreters was stressed, as was the role of trusted individuals, including existing service providers, Community Connectors and family members in providing a solid base for participant understanding of the NDIS. Conclusions: Cultural competence in disability assessment and planning can be strengthened through multi-level engagement with the Aboriginal community-controlled sector and community leaders. Implementing mechanisms to enable the involvement of families, trusted service providers and Community Connectors can support a more meaningful understanding of individuals’ needs within their cultural context and in relation to their cultural roles

Development and Validation of a Prediction Model for Future Estimated Glomerular Filtration Rate in People With Type 2 Diabetes and Chronic Kidney Disease

Importance: Type 2 diabetes increases the risk of progressive diabetic kidney disease, but reliable prediction tools that can be used in clinical practice and aid in patients' understanding of disease progression are currently lacking. Objective: To develop and externally validate a model to predict future trajectories in estimated glomerular filtration rate (eGFR) in adults with type 2 diabetes and chronic kidney disease using data from 3 European multinational cohorts. Design, Setting, and Participants: This prognostic study used baseline and follow-up information collected between February 2010 and December 2019 from 3 prospective multinational cohort studies: PROVALID (Prospective Cohort Study in Patients with Type 2 Diabetes Mellitus for Validation of Biomarkers), GCKD (German Chronic Kidney Disease), and DIACORE (Diabetes Cohorte). A total of 4637 adult participants (aged 18-75 years) with type 2 diabetes and mildly to moderately impaired kidney function (baseline eGFR of ≥30 mL/min/1.73 m2) were included. Data were analyzed between June 30, 2021, and January 31, 2023. Main Outcomes and Measures: Thirteen variables readily available from routine clinical care visits (age, sex, body mass index; smoking status; hemoglobin A1c[mmol/mol and percentage]; hemoglobin, and serum cholesterol levels; mean arterial pressure, urinary albumin-creatinine ratio, and intake of glucose-lowering, blood-pressure lowering, or lipid-lowering medication) were selected as predictors. Repeated eGFR measurements at baseline and follow-up visits were used as the outcome. A linear mixed-effects model for repeated eGFR measurements at study entry up to the last recorded follow-up visit (up to 5 years after baseline) was fit and externally validated. Results: Among 4637 adults with type 2 diabetes and chronic kidney disease (mean [SD] age at baseline, 63.5 [9.1] years; 2680 men [57.8%]; all of White race), 3323 participants from the PROVALID and GCKD studies (mean [SD] age at baseline, 63.2 [9.3] years; 1864 men [56.1%]) were included in the model development cohort, and 1314 participants from the DIACORE study (mean [SD] age at baseline, 64.5 [8.3] years; 816 men [62.1%]) were included in the external validation cohort, with a mean (SD) follow-up of 5.0 (0.6) years. Updating the random coefficient estimates with baseline eGFR values yielded improved predictive performance, which was particularly evident in the visual inspection of the calibration curve (calibration slope at 5 years: 1.09; 95% CI, 1.04-1.15). The prediction model had good discrimination in the validation cohort, with the lowest C statistic at 5 years after baseline (0.79; 95% CI, 0.77-0.80). The model also had predictive accuracy, with an R2ranging from 0.70 (95% CI, 0.63-0.76) at year 1 to 0.58 (95% CI, 0.53-0.63) at year 5. Conclusions and Relevance: In this prognostic study, a reliable prediction model was developed and externally validated; the robust model was well calibrated and capable of predicting kidney function decline up to 5 years after baseline. The results and prediction model are publicly available in an accompanying web-based application, which may open the way for improved prediction of individual eGFR trajectories and disease progression.</p

Disturbed neuronal ER-Golgi sorting of unassembled glycine receptors suggests altered subcellular processing is a cause of human hyperekplexia.

Recent studies on the pathogenic mechanisms of recessive hyperekplexia indicate disturbances in glycine receptor (GlyR) α1 biogenesis. Here, we examine the properties of a range of novel glycine receptor mutants identified in human hyperekplexia patients using expression in transfected cell lines and primary neurons. All of the novel mutants localized in the large extracellular domain of the GlyR α1 have reduced cell surface expression with a high proportion of receptors being retained in the ER, although there is forward trafficking of glycosylated subpopulations into the ER-Golgi intermediate compartment and cis-Golgi compartment. CD spectroscopy revealed that the mutant receptors have proportions of secondary structural elements similar to wild-type receptors. Two mutants in loop B (G160R, T162M) were functional, but none of those in loop D/β2-3 were. One nonfunctional truncated mutant (R316X) could be rescued by coexpression with the lacking C-terminal domain. We conclude that a proportion of GlyR α1 mutants can be transported to the plasma membrane but do not necessarily form functional ion channels. We suggest that loop D/β2-3 is an important determinant for GlyR trafficking and functionality, whereas alterations to loop B alter agonist potencies, indicating that residues here are critical elements in ligand binding.This work was supported by the Deutsche Forschungsgemeinschaft (Grant DFG VI586 to C.V.) and the European Union (FP7 project Neurocypres to C.J.K., K.L.P., and S.C.R.L.). N. Schaefer and G.L. are supported by the GSLS Wuerzburg. S.C.R.L. is a Wellcome Trust Senior Research Fellow in Basic Biomedical Research.This is the author accepted manuscript. The final version is available from the Society of Neuroscience via http://dx.doi.org/10.1523/JNEUROSCI.1509-14.201

ELM—the database of eukaryotic linear motifs

Linear motifs are short, evolutionarily plastic components of regulatory proteins and provide low-affinity interaction interfaces. These compact modules play central roles in mediating every aspect of the regulatory functionality of the cell. They are particularly prominent in mediating cell signaling, controlling protein turnover and directing protein localization. Given their importance, our understanding of motifs is surprisingly limited, largely as a result of the difficulty of discovery, both experimentally and computationally. The Eukaryotic Linear Motif (ELM) resource at http://elm.eu.org provides the biological community with a comprehensive database of known experimentally validated motifs, and an exploratory tool to discover putative linear motifs in user-submitted protein sequences. The current update of the ELM database comprises 1800 annotated motif instances representing 170 distinct functional classes, including approximately 500 novel instances and 24 novel classes. Several older motif class entries have been also revisited, improving annotation and adding novel instances. Furthermore, addition of full-text search capabilities, an enhanced interface and simplified batch download has improved the overall accessibility of the ELM data. The motif discovery portion of the ELM resource has added conservation, and structural attributes have been incorporated to aid users to discriminate biologically relevant motifs from stochastically occurring non-functional instance

Genetic studies of paired metabolomes reveal enzymatic and transport processes at the interface of plasma and urine.

The kidneys operate at the interface of plasma and urine by clearing molecular waste products while retaining valuable solutes. Genetic studies of paired plasma and urine metabolomes may identify underlying processes. We conducted genome-wide studies of 1,916 plasma and urine metabolites and detected 1,299 significant associations. Associations with 40% of implicated metabolites would have been missed by studying plasma alone. We detected urine-specific findings that provide information about metabolite reabsorption in the kidney, such as aquaporin (AQP)-7-mediated glycerol transport, and different metabolomic footprints of kidney-expressed proteins in plasma and urine that are consistent with their localization and function, including the transporters NaDC3 (SLC13A3) and ASBT (SLC10A2). Shared genetic determinants of 7,073 metabolite-disease combinations represent a resource to better understand metabolic diseases and revealed connections of dipeptidase 1 with circulating digestive enzymes and with hypertension. Extending genetic studies of the metabolome beyond plasma yields unique insights into processes at the interface of body compartments