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Cole, V.

Publications and source records attributed to Cole, V..

3 recordsLinked to original sources

Benchmarking sequence performance on the DNBSEQ-T7 using Genome in a Bottle reference genomes

Advances in sequencing technologies have improved the accuracy, throughput, and completeness of human genome characterization, enabling more reliable detection of genetic variation. Well-characterized reference genomes are critical for benchmarking sequencing platforms and bioinformatics analysis pipelines. Here, we present whole genome sequencing datasets generated for the Ashkenazi Jewish trio reference samples from the Genome in a Bottle Consortium. Libraries were prepared using three distinct MGI-based workflows: PCR-free library preparation, FastFS DNA library preparation, and Universal DNA library preparation. Sequencing was performed on the MGI DNBSEQ-T7 platform, generating a minimum of 400 million paired-end reads per sample, corresponding to 30X mean genome coverage. Raw reads were processed using a standardized GATK bioinformatics workflow. Sequencing performance and variant detection accuracy were evaluated using the Genome in a Bottle high-confidence benchmark variant sets. All workflows demonstrated high sequencing quality and concordance with GIAB benchmark truth sets, with PCR-free libraries showing the strongest indel calling performance and lowest Mendelian violation rates across the Ashkenazi trio. This dataset provides a resource for benchmarking DNBSEQ-T7 sequencing and bioinformatics workflows, and for evaluating the impact of library preparation strategies on whole genome variant detection performance.

bioinformatics↗

The structural basis of fatty acid elongation by the ELOVL elongases

Very long chain fatty acids (VLCFAs) are essential building blocks for synthesis of the ceramides and sphingolipids required for nerve, skin and retina function and 3-keto acyl-CoA synthases (ELOVL elongases) perform the first step in the FA elongation cycle. Although ELOVLs are implicated in common diseases including insulin resistance, hepatic steatosis and Parkinsons, their underlying molecular mechanisms are unknown. Here we report the structure of the human ELOVL7 elongase, which includes an inverted transmembrane barrel structure surrounding a 35 [A] long tunnel containing a covalently-attached product analogue. The structure reveals the substrate binding sites in the tunnel and an active site deep in the membrane including the canonical ELOVL HxxHH sequence. This indicates a ping-pong mechanism for catalysis, involving unexpected covalent histidine adducts. The unusual substrate-binding arrangement and chemistry suggest mechanisms for selective ELOVL inhibition, relevant for diseases where VLCFAs accumulate such as X-linked adrenoleukodystrophy.

biochemistry↗

2′-5′-Oligoadenylate synthetase-like protein inhibits intracellular M. tuberculosis replication and promotes proinflammatory cytokine secretion

Host cytoplasmic surveillance pathways are known to elicit type I interferon (IFN) responses which are crucial to antimicrobial defense mechanisms. Oligoadenylate synthetase-like (OASL) protein has been extensively characterized as a part of the anti-viral mechanism, however a number of transcriptomic studies reveal its upregulation in response to infection with a wide variety of intracellular bacterial pathogens. To date, there is no evidence documenting the role (if any) of OASL during mycobacterium tuberculosis infection. Using two pathogenic strains differing in virulence only, as well as the non-pathogenic M. bovis BCG strain, we observed that pathogenicity and virulence strongly induced OASL expression after 24 h of infection. Further, we observed that OASL knock down led to a significant increase in M. tb CFU counts 96 h post-infection in comparison to the respective controls. Luminex revealed that OASL silencing significantly decreased IL-1{beta}, TNF- and MCP-1 secretion in THP-1 cells and had no effect on IL-10 secretion. We therefore postulate that OASL regulates pro-inflammatory mediators such as cytokines and chemokines which suppress intracellular mycobacterial growth and survival.

cell biology↗