| 1. |
- Maróti, Zoltán, et al.
(author)
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The genetic origin of Huns, Avars, and conquering Hungarians
- 2022
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In: Current Biology. - : Elsevier BV. - 0960-9822 .- 1879-0445. ; 32:13, s. 2858-2870, 2858–2870.e1–e7
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Journal article (peer-reviewed)abstract
- Huns, Avars, and conquering Hungarians were migration-period nomadic tribal confederations that arrived in three successive waves in the Carpathian Basin between the 5th and 9th centuries. Based on the historical data, each of these groups are thought to have arrived from Asia, although their exact origin and relation to other ancient and modern populations have been debated. Recently, hundreds of ancient genomes were analyzed from Central Asia, Mongolia, and China, from which we aimed to identify putative source populations for the above-mentioned groups. In this study, we have sequenced 9 Hun, 143 Avar, and 113 Hungarian conquest period samples and identified three core populations, representing immigrants from each period with no recent European ancestry. Our results reveal that this “immigrant core” of both Huns and Avars likely originated in present day Mongolia, and their origin can be traced back to Xiongnus (Asian Huns), as suggested by several historians. On the other hand, the “immigrant core” of the conquering Hungarians derived from an earlier admixture of Mansis, early Sarmatians, and descendants of late Xiongnus. We have also shown that a common “proto-Ugric” gene pool appeared in the Bronze Age from the admixture of Mezhovskaya and Nganasan people, supporting genetic and linguistic data. In addition, we detected shared Hun-related ancestry in numerous Avar and Hungarian conquest period genetic outliers, indicating a genetic link between these successive nomadic groups. Aside from the immigrant core groups, we identified that the majority of the individuals from each period were local residents harboring “native European” ancestry.
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| 2. |
- Gustafsson, Gabriel, et al.
(author)
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Secretion and uptake of α-synuclein via extracellular vesicles in cultured cells
- 2018
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In: Cellular and molecular neurobiology. - : Springer Science and Business Media LLC. - 0272-4340 .- 1573-6830. ; 38:8, s. 1539-1550
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Journal article (peer-reviewed)abstract
- In Parkinson’s disease and other Lewy body disorders, the propagation of pathology has been accredited to the spreading of extracellular α-synuclein (α-syn). Although the pathogenic mechanisms are not fully understood, cell-to-cell transfer of α-syn via exosomes and other extracellular vesicles (EVs) has been reported. Here, we investigated whether altered molecular properties of α-syn can influence the distribution and secretion of α-syn in human neuroblastoma cells. Different α-syn variants, including α-syn:hemi-Venus and disease-causing mutants, were overexpressed and EVs were isolated from the conditioned medium. Of the secreted α-syn, 0.1–2% was associated with vesicles. The major part of EV α-syn was attached to the outer membrane of vesicles, whereas a smaller fraction was found in their lumen. For α-syn expressed with N-terminal hemi-Venus, the relative levels associated with EVs were higher than for WT α-syn. Moreover, such EV-associated α-syn:hemi-Venus species were internalized in recipient cells to a higher degree than the corresponding free-floating forms. Among the disease-causing mutants, A53T α-syn displayed an increased association with EVs. Taken together, our data suggest that α-syn species with presumably lost physiological functions or altered aggregation properties may shift the cellular processing towards vesicular secretion. Our findings thus lend further support to the tenet that EVs can mediate spreading of harmful α-syn species and thereby contribute to the pathology in α-synucleinopathies.
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| 3. |
- Hanlon, Killian S., et al.
(author)
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High levels of AAV vector integration into CRISPR-induced DNA breaks
- 2019
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In: Nature Communications. - : NATURE PUBLISHING GROUP. - 2041-1723. ; 10
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Journal article (peer-reviewed)abstract
- Adeno-associated virus (AAV) vectors have shown promising results in preclinical models, but the genomic consequences of transduction with AAV vectors encoding CRISPR-Cas nucleases is still being examined. In this study, we observe high levels of AAV integration (up to 47%) into Cas9-induced double-strand breaks (DSBs) in therapeutically relevant genes in cultured murine neurons, mouse brain, muscle and cochlea. Genome-wide AAV mapping in mouse brain shows no overall increase of AAV integration except at the CRISPR/Cas9 target site. To allow detailed characterization of integration events we engineer a miniature AAV encoding a 465 bp lambda bacteriophage DNA (AAV-lambda 465), enabling sequencing of the entire integrated vector genome. The integration profile of AAV-465 lambda in cultured cells display both full-length and fragmented AAV genomes at Cas9 on-target sites. Our data indicate that AAV integration should be recognized as a common outcome for applications that utilize AAV for genome editing.
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| 4. |
- Konstantinidis, Evangelos, et al.
(author)
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CRISPR-Cas9 treatment partially restores amyloid-β 42/40 in human fibroblasts with the Alzheimer's disease PSEN1 M146L mutation
- 2022
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In: Molecular Therapy Nucleic Acids. - : Elsevier BV. - 2162-2531. ; 28, s. 450-461
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Journal article (peer-reviewed)abstract
- Presenilin 1 (PS1) is a central component of γ-secretase, an enzymatic complex involved in the generation of the amyloid-β (Aβ) peptide that deposits as plaques in the Alzheimer’s disease (AD) brain. The M146L mutation in the PS1 gene (PSEN1) leads to an autosomal dominant form of early-onset AD by promoting a relative increase in the generation of the more aggregation-prone Aβ42. This change is evident not only in the brain but also in peripheral cells of mutation carriers. In this study we used the CRISPR-Cas9 system from Streptococcus pyogenes to selectively disrupt the PSEN1M146L allele in human fibroblasts. A disruption of more than 50% of mutant alleles was observed in all CRISPR-Cas9-treated samples, resulting in reduced extracellular Aβ42/40 ratios. Fluorescence resonance energy transfer-based conformation and western blot analyses indicated that CRISPR-Cas9 treatment also affects the overall PS1 conformation and reduces PS1 levels. Moreover, our guide RNA did not lead to any detectable editing at the highest-ranking candidate off-target sites identified by ONE-seq and CIRCLE-seq. Overall, our data support the effectiveness of CRISPR-Cas9 in selectively targeting the PSEN1M146L allele and counteracting the AD-associated phenotype. We believe that this system could be developed into a therapeutic strategy for patients with this and other dominant mutations leading to early-onset AD.
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| 5. |
- Molisak, Agnieszka, et al.
(author)
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CRISPR/Cas9 as a tool to disrupt wild-type and A53T SNCA in sporadic and familial Parkinson’s disease
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Other publication (other academic/artistic)abstract
- Parkinson’s Disease (PD) is characterized by pathological accumulation of α-synuclein (αSyn) as Lewy bodies and Lewy neurites in the brain. Current treatment strategies can only alleviate the symptoms but do not interfere with the disease progression. With the discovery of the CRISPR/Cas9 gene editing tool, it has become possible to target the generation of pathological protein aggregates at the DNA level. Disrupting the αSyn gene (SNCA) could prevent the formation of Lewy-related pathologies. Here, we have designed two CRISPR/Cas9-based approaches by using guide RNAs (gRNAs) that are targeting either wild-type (WT) SNCA (pan-SNCA) or mutant A53T SNCA that causes early-onset familial PD. We could demonstrate that plasmid vector-mediated transfection of the pan-SNCA gRNA led to robust allelic disruption in HEK293T cells and human fibroblasts and that the editing efficiency was further increased with the use of a lentiviral transduction system. In addition, the SNCA A53T gRNA was specific towards the mutation site, but resulted in low and inconsistent targeting efficiencies in human patient fibroblasts carrying the SNCA A53T mutation. Our results indicate that SNCA can be targeted by CRISPR/Cas9, although the system efficiency varies across different cell types. In the future, systemically administered gene-editing treatments based on CRISPR/Cas9 could provide a valid therapeutic approach for PD patients.
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