Publications by authors named "Alexandra Busley"

Takotsubo Syndrome (TTS) is a potentially life-threatening disease characterized by a transient left ventricular apical akinesia in response to β-adrenergic overstimulation. Since a genetic predisposition is assumed, we generated an iPSC-line carrying a p.F189L mutation in the calcium buffering protein Calsequestrin 2 (CasQ2).

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Noonan syndrome patients harboring causative variants in LZTR1 are particularly at risk to develop severe and early-onset hypertrophic cardiomyopathy. In this study, we investigate the mechanistic consequences of a homozygous variant LZTR1 by using patient-specific and CRISPR-Cas9-corrected induced pluripotent stem cell (iPSC) cardiomyocytes. Molecular, cellular, and functional phenotyping in combination with in silico prediction identify an LZTR1-specific disease mechanism provoking cardiac hypertrophy.

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Article Synopsis
  • Noonan syndrome (NS), a common genetic disorder linked to the RAS-MAPK pathway, is associated with variants like the Ser257Leu substitution in RAF1, which is particularly connected to severe heart disease (HCM).
  • Researchers created three-dimensional cardiac models from stem cells of NS patients with specific RAF1 mutations to study the relationship between these genetic changes and heart tissue abnormalities.
  • Findings showed that the mutated RAF1 caused changes in heart cell structure, shortening of key protein elements, and impaired heart function, but these issues could partially be reversed by inhibiting the MEK pathway.
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Patients harboring causative gene variants in RAS GTPase MRAS develop Noonan syndrome and early-onset hypertrophic cardiomyopathy. Here, we describe the generation of a human iPSC line harboring the Noonan syndrome-associated MRAS p.G23V variant by using CRISPR/Cas9 technology.

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Activating KRAS codon 12 gene variants are known to cause severe RAS-MAPK and PI3K-AKT signaling pathway hyperactivity and are frequently involved in the development of various carcinomas. Here, we describe the generation of a human iPSC line harboring the common oncogenic KRAS p.G12V variant by using CRISPR/Cas9 technology.

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Background: Brugada syndrome (BrS) is causing sudden cardiac death (SCD) mainly at young age. Studying the underlying mechanisms associated with BrS type I electrocardiogram (ECG) changes in the presence of fever and roles of autophagy for BrS remains lacking.

Objectives: We sought to study the pathogenic role of an SCN5A gene variant for BrS with fever-induced type 1 ECG phenotype.

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Mammalian prions, the pathogens that cause transmissible spongiform encephalopathies, propagate by self-perpetuating the structural information stored in the abnormally folded, aggregated conformer (PrPSc) of the host-encoded prion protein (PrPC). To date, no structural model related to prion assembly organization satisfactorily describes how strain-specified structural information is encoded and by which mechanism this information is transferred to PrPC. To achieve progress on this issue, we correlated the PrPSc quaternary structural transition from three distinct prion strains during unfolding and refolding with their templating activity.

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