10 research outputs found
A recurrent mitochondrial p.Trp22Arg NDUFB3 variant causes a distinctive facial appearance, short stature and a mild biochemical and clinical phenotype
Background Isolated Complex I deficiency is the most common paediatric mitochondrial disease presentation, associated with poor prognosis and high mortality. Complex I comprises 44 structural subunits with at least 10 ancillary proteins; mutations in 29 of these have so far been associated with mitochondrial disease but there are limited genotype-phenotype correlations to guide clinicians to the correct genetic diagnosis.
Methods Patients were analysed by whole-exome sequencing, targeted capture or candidate gene sequencing. Clinical phenotyping of affected individuals was performed.
Results We identified a cohort of 10 patients from 8 families (7 families are of unrelated Irish ancestry) all of whom have short stature (C, p.Trp22Arg NDUFB3 variant. Two sibs presented with primary short stature without obvious metabolic dysfunction. Analysis of skeletal muscle from three patients confirmed a defect in Complex I assembly.
Conclusions Our report highlights that the long-term prognosis related to the p.Trp22Arg NDUFB3 mutation can be good, even for some patients presenting in acute metabolic crisis with evidence of an isolated Complex I deficiency in muscle. Recognition of the distinctive facial featuresâparticularly when associated with markers of mitochondrial dysfunction and/or Irish ancestryâshould suggest screening for the p.Trp22Arg NDUFB3 mutation to establish a genetic diagnosis, circumventing the requirement of muscle biopsy to direct genetic investigations
Achieving the "triple aim" for inborn errors of metabolism: a review of challenges to outcomes research and presentation of a new practice-based evidence framework
Across all areas of health care, decision makers are in pursuit of what
Berwick and colleagues have called the âtriple aimâ: improving patient
experiences with care, improving health outcomes, and managing
health system impacts. This is challenging in a rare disease context, as
exemplified by inborn errors of metabolism. There is a need for evaluative
outcomes research to support effective and appropriate care for
inborn errors of metabolism. We suggest that such research should
consider interventions at both the level of the health system (e.g., early
detection through newborn screening, programs to provide access to
treatments) and the level of individual patient care (e.g., orphan drugs,
medical foods). We have developed a practice-
based evidence framework
to guide outcomes research for inborn errors of metabolism.
Focusing on outcomes across the triple aim, this framework integrates
three priority themes: tailoring care in the context of clinical heterogeneity;
a shift from âurgent careâ to âopportunity for improvementâ;
and the need to evaluate the comparative effectiveness of emerging
and established therapies. Guided by the framework, a new Canadian
research network has been established to generate knowledge that will
inform the design and delivery of health services for patients with
inborn errors of metabolism and other rare diseases.This work was supported by a CIHR Emerging Team Grant (âEmerging
team in rare diseases: acheiving the âtriple aimâ for inborn errors
of metabolism,â B.K. Potter, P. Chakraborty, and colleagues, 2012â
2017, grant no. TR3â119195). Current investigators and collaborators
in the Canadian Inherited Metabolic Diseases Research Network
are: B.K. Potter, P. Chakraborty, J. Kronick, D. Coyle, K. Wilson, M.
Brownell, R. Casey, A. Chan, S. Dyack, L. Dodds, A. Feigenbaum, D.
Fell, M. Geraghty, C. Greenberg, S. Grosse, A. Guttmann, A. Khan,
J. Little, B. Maranda, J. MacKenzie, A. Mhanni, F. Miller, G. Mitchell,
J. Mitchell, M. Nakhla, M. Potter, C. Prasad, K. Siriwardena, K.N.
Speechley, S. Stocker, L. Turner, H. Vallance, and B.J. Wilson. Members
of our external advisory board are D. Bidulka, T. Caulfield, J.T.R.
Clarke, C. Doiron, K. El Emam, J. Evans, A. Kemper, W. McCormack,
and A. Stephenson Julian. J. Little is supported by a Canada Research
Chair in Human Genome Epidemiology. K. Wilson is supported by a
Canada Research Chair in Public Health Policy
Formin-mediated bridging of cell wall, plasma membrane, and cytoskeleton in symbiotic infections of Medicago truncatula
International audienceLegumes have maintained the ability to associate with rhizobia to sustain the nitrogen-fixing root nodule symbiosis (RNS). In Medicago truncatula, the Nod factor (NF)-dependent intracellular root colonization by Sinorhizobium meliloti initiates from young, growing root hairs. They form rhizobial traps by physically curling around the symbiont. Although alterations in root hair morphology like branching and swelling have been observed in other plants in response to drug treatments or genetic perturbations, full root hair curling represents a rather specific invention in legumes. The entrapment of the symbiont completes with its full enclosure in a structure called the âinfection chamberâ (IC), from which a tube-like membrane channel, the âinfection threadâ (IT), initiates. All steps of rhizobium-induced root hair alterations are aided by a tip-localized cytosolic calcium gradient, global actin re-arrangements, and dense subapical fine actin bundles that are required for the delivery of Golgi-derived vesicles to the root hair tip. Altered actin dynamics during early responses to NFs or rhizobia have mostly been shown in mutants that are affected in the actin-related SCAR/WAVE complex. Here, we identified a polarly localized SYMBIOTIC FORMIN 1 (SYFO1) to be required for NF-dependent alterations in membrane organization and symbiotic root hair responses. We demonstrate that SYFO1 mediates a continuum between the plasma membrane and the cell wall that is required for the onset of rhizobial infections
Stabilization of membrane topologies by proteinaceous remorin scaffolds
In plants, plasma membrane topologies are predominantly driven by the cell wall. In this study, the authors demonstrate that remorin proteins can take over these functions at specialized, unwalled plasma membranes such as infection droplets associated with symbiotic infection threads
Centrosomal Actin Assembly is Required for Proper Mitotic Spindle Formation and Chromosome Congression
The Global Phosphorylation Landscape of SARS-CoV-2 Infection
International audienceThe causative agent of the coronavirus disease 2019 (COVID-19) pandemic, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has infected millions and killed hundreds of thousands of people worldwide, highlighting an urgent need to develop antiviral therapies. Here we present a quantitative mass spectrometry-based phosphoproteomics survey of SARS-CoV-2 infection in Vero E6 cells, revealing dramatic rewiring of phosphorylation on host and viral proteins. SARS-CoV-2 infection promoted casein kinase II (CK2) and p38 MAPK activation, production of diverse cytokines, and shutdown of mitotic kinases, resulting in cell cycle arrest. Infection also stimulated a marked induction of CK2-containing filopodial protrusions possessing budding viral particles. Eighty-seven drugs and compounds were identified by mapping global phosphorylation profiles to dysregulated kinases and pathways. We found pharmacologic inhibition of the p38, CK2, CDK, AXL, and PIKFYVE kinases to possess antiviral efficacy, representing potential COVID-19 therapies