Project description:The glycine-51 (G51) codon in exon 3 of the rat Snca gene, encoding alpha-synuclein, was mutated to aspartic acid using CRISPR/Cas9 to generate the SncaG51D rat model of Parkinson’s (Morley et al. 2023). The G51D mutation causes an aggressive form of Parkinson’s and dementia with Lewy bodies in humans. The brains from four 6-month old rats of wild-type, heterozygous, and homozygous genotypes (Snca+/+, SncaG51D/+ and SncaG51D/G51D) were harvested and all 12 brains were bisected down the midline. Frontal cortex was isolated from one half, and synaptosomes were prepared from the other half. Following quality control the samples were processed for TMT-mass spectrometry by the Fingerprints Facility, University of Dundee. MaxQuant Version 1.6.0.16 was used for the assignment of peptides to protein using the uniport-rat-jan2018.fasta file. Pairwise comparisons were made between the different mutant samples and Snca+/+ for both the cortical and synaptosome samples. Morley V, Dolt KS, Alcaide-Corral CJ, Walton T, Lucatelli C, Mashimo T, Tavares AAS & Kunath T (2023) In vivo18F-DOPA PET imaging identifies a dopaminergic deficit in a rat model with a G51D α-synuclein mutation. Front. Neurosci. 17, 1095761.
Project description:The high mutation rate across the whole melanoma genome provides a major challenge in stratifying true driver events from the background mutations. Many non-coding recurrent events, such as those occurred in enhancer, can shape tumor evolution, emphasizing the importance in systematically deciphering enhancer disruptions in melanoma. Here, we leveraged 297 melanoma whole-genome sequencing (WGS) samples to prioritize highly recurrent regions (HRRs). By performing a genome-scale CRISPR interference (CRISPRi) screen on HRR-associated enhancers in melanoma cells, we identified 66 significant hits which could have tumor-suppressive roles. These functional enhancers show unique mutational patterns independent of classical significantly mutated genes in melanoma. Target gene analysis for the essential enhancers revealed many known and hidden mechanisms underlying melanoma development. We demonstrated that a super enhancer element could modulate melanoma cell proliferation by targeting MEF2A and another distal enhancer was able to sustain PTEN tumor-suppressive potential via long-range interaction. Our study established a catalogue of crucial enhancers and their target genes in melanoma development and progression, which illuminates the identification of novel mechanism of dysregulation for melanoma driver genes and new therapeutic targeting strategy.
Project description:We evaluated linked-read whole genome sequencing (WGS) for detection of structural chromosomal rearrangements in primary samples of varying DNA quality from 12 patients diagnosed with ALL. Linked-read WGS enabled precise, allele-specific, digital karyotyping at a base-pair resolution for a wide range of structural variants including complex rearrangements, aneuploidy assessment and gene deletions. Additional RNA-sequencing and copy number aberrations (CNA) data from Illumina Infinium arrays were also generated and assessed against the linked-read WGS data. RNA-sequencing data was used to support structural chromosomal rearrangements detected in the linked-read WGS data by detecting expressed fusion genes as a consequence of the rearrangements. Illumina Infinium arrays (450k array and/or SNP array) were used to assess CNA status to further support the findings in the linked-read WGS data. The processed CNA data from the primary ALL patient samples has been deposited to GEO. RNA-sequencing, linked-read WGS data, and raw SNP array data from the primary ALL patient samples will not be deposited because the patient/parent consent does not cover depositing data that may be used for large-scale determination of germline variants in a repository. The ALL samples were collected 10-20 years ago from pediatric patients aged 2-15 years, some whom have deceased. The linked-read WGS data and the RNA-sequencing data sets generated in the study are available upon reasonable request from the corresponding author Jessica.Nordlund@medsci.uu.se.