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Biology subjects

Castillo, N.

Publications and source records attributed to Castillo, N..

2 recordsLinked to original sources

Cryo-FIB lamellae enable ultra-high excitation laser intensities for cryogenic super-resolution fluorescence imaging

Super-resolution cryogenic correlative light and electron microscopy (SR-cryo-CLEM) integrates molecular specificity and structure on the single-molecule level, but contemporary approaches require low laser powers to preserve specimen vitrification. Here, we perform SR-cryo-CLEM via single molecule localization microscopy (SMLM) on thin biological lamellae and demonstrate that their geometry and minimally-absorbent composition permit excitation laser powers three orders of magnitude higher than standard cryo-EM grids, allowing improved localization precision and imaging speeds.

molecular biology↗

High accuracy DNA sequencing on a small, scalable platform via electrical detection of single base incorporations

High throughput DNA sequencing technologies have undergone tremendous development over the past decade. Although optical detection-based sequencing has constituted the majority of data output, it requires a large capital investment and aggregation of samples to achieve optimal cost per sample. We have developed a novel electronic detection-based platform capable of accurately detecting single base incorporations. The GenapSys technology with its electronic detection modality allows the system to be compact, accessible, and affordable. We demonstrate the performance of the system by sequencing several different microbial genomes with varying GC content. The platform is capable of generating up to 2 Gb of high-quality nucleic acid sequence in a single run. We routinely generate sequence data that exceeds 99% raw accuracy with read lengths of up to 175 bp. Average quality scores remain above Q30 (99.9% raw sequencing accuracy) beyond 150 bp, with more than 85% of total bases at or above Q30. The utility of the platform is highlighted by targeted sequencing of the human genome. We show high concordance of SNP detection on the human NA12878 HapMap cell line with data generated on the Illumina sequencing platform. In addition, we sequenced a targeted panel of cancer-associated genes in a well characterized reference standard. With multiple library preparation approaches on this sample, we were able to identify low frequency mutations at expected allele frequencies.

genomics↗