Intracellular and Extracellular Vesicle miRNA Signatures in Human iPSC-Derived Neural Stem Cells and Floor Plate Progenitors.

Refined control of intrinsic and extrinsic signals is critical for specific neuronal differentiation. Here, we differentiated human induced pluripotent stem cells (hiPSCs) from three different healthy donors into neural stem cells (NSCs) and floor plate progenitors (FPPs; progenitors of dopaminergic neurons) and further performed intracellular and extracellular vesicles' (EVs) miRNA profiling. While NSC and FPP cells differed significantly in levels of only 8 intracellular miRNAs, their differences were more evident in the EV miRNAs with 27 differentially expressed miRNAs.

A hexamer tandem repeat RNA embedded within an SVA retrotransposon drives R-loop formation and neurodegeneration.

Retrotransposon activation is emerging as a significant factor in neurodegenerative disease pathogenesis. SINE-VNTR-Alu (SVAs) are hominid-specific retrotransposons that create genetic variation through insertion polymorphisms and variable short tandem repeat (STR) lengths. We investigate how the SVA (CCCTCT) STR contributes to the striatal neurodegenerative disorder X-linked dystonia parkinsonism (XDP), where the repeat expansion length within the pathogenic SVA is inversely correlated with age at disease onset.

Engineering of CD63 Enables Selective Extracellular Vesicle Cargo Loading and Enhanced Payload Delivery.

Extracellular vesicles (EVs) are mediators of intercellular communication through the transfer of nucleic acids, lipids and proteins between cells. This property makes bioengineered EVs promising therapeutic vectors. However, it remains challenging to isolate EVs with a therapeutic payload due to the heterogeneous nature of cargo loading into EVs.

is a genetic modifier of somatic repeat instability in X-linked dystonia parkinsonism.

X-linked dystonia parkinsonism (XDP) is a progressive adult-onset neurogenerative disorder caused by the insertion of a SINE-VNTR-Alu (SVA) retrotransposon in gene. One element of the SVA is a tandem polymorphic CCCTCT repeat tract whose length inversely correlates with the age of disease onset. Previous observations that the repeat exhibits length-dependent somatic expansion and that XDP onset is modified by variation in DNA repair gene indicated that somatic repeat expansion is an important disease driver.

Non-invasive detection of allele-specific CRISPR-SaCas9-KKH disruption of DYT1 allele in a xenograft mouse model.

DYT1 dystonia is a neurological movement disorder characterized by a dominant 3-base pair deletion (ΔGAG) in the gene. This study demonstrates a gene-editing approach that selectively targets the ΔGAG mutation in the DYT1 allele while safeguarding the wild-type (WT) allele. We optimized an adeno-associated virus (AAV) vector-compatible variant of the Cas9 nuclease ortholog (SaCas9-KKH) in DYT1 patient-derived human neuronal progenitor cells (hNPCs).