Despite extensive effort to reveal the genetic basis of complex phenotypic variation, studies typically explain only a fraction of trait heritability. It has been hypothesized that individually rare hidden structural variants (SVs) could account for a significant fraction of variation in complex traits. To investigate this hypothesis, we assembled 14 Drosophila melanogaster genomes and systematically identified more than 20,000 euchromatic SVs, of which ~40% are invisible to high specificity short read genotyping approaches. SVs are common in Drosophila genes, with almost one third of diploid individuals harboring an SV in genes larger than 5kb, and nearly a quarter harboring multiple…
Cocci-shaped Sporosarcina strains are currently one of the few known cocci-shaped spore-forming bacteria, yet we know very little about the genomics. The goal of this study is to utilize comparative genomics to investigate the diversity of cocci-shaped Sporosarcina strains that differ in their geographical isolation and show different nutritional requirements.For this study, we sequenced 28 genomes of cocci-shaped Sporosarcina strains isolated from 13 different locations around the world. We generated the first six complete genomes and methylomes utilizing PacBio sequencing, and an additional 22 draft genomes using Illumina sequencing. Genomic analysis revealed that cocci-shaped Sporosarcina strains contained an average genome…
The yeast Saccharomyces cerevisiae has emerged as a superior model organism. Selection of distinct laboratory strains of S. cerevisiae with unique phenotypic properties, such as superior mating or sporulation efficiencies, has facilitated advancements in research. W303 is one such laboratory strain that is closely related to the first completely sequenced yeast strain, S288C. In this work, we provide a high-quality, annotated genome sequence for W303 for utilization in comparative analyses and genome-wide studies. Approximately 9500 variations exist between S288C and W303, affecting the protein sequences of ~700 genes. A listing of the polymorphisms and divergent genes is provided for researchers…
Genome assemblies that are accurate, complete and contiguous are essential for identifying important structural and functional elements of genomes and for identifying genetic variation. Nevertheless, most recent genome assemblies remain incomplete and fragmented. While long molecule sequencing promises to deliver more complete genome assemblies with fewer gaps, concerns about error rates, low yields, stringent DNA requirements and uncertainty about best practices may discourage many investigators from adopting this technology. Here, in conjunction with the platinum standard Drosophila melanogaster reference genome, we analyze recently published long molecule sequencing data to identify what governs completeness and contiguity of genome assemblies. We also…
The zoonotic pathogen Borrelia hermsii bears its multiple paralogous genes for variable antigens on several linear plasmids. Application of combined long-read and short-read next-generation sequencing provided complete sequences for antigen-encoding plasmids as well as other linear and circular plasmids and the linear chromosome of the genome. Copyright © 2016 Barbour.
Based on chromosome sequences, the human pathogen Borrelia miyamotoi phylogenetically clusters with species that cause relapsing fever. But atypically for relapsing fever agents, B. miyamotoi is transmitted not by soft ticks but by hard ticks, which also are vectors of Lyme disease Borrelia species. To further assess the relationships of B. miyamotoi to species that cause relapsing fever, I investigated extrachromosomal sequences of a North American strain with specific attention on plasmid-borne vsp and vlp genes, which are the underpinnings of antigenic variation during relapsing fever. For a hybrid approach to achieve assemblies that spanned more than one of the…
Pseudoalteromonas sp. strain OCN003 is a marine gammaproteobacterium that was isolated from a diseased colony of the common Hawaiian reef coral, Montipora capitata, found on a reef surrounding Moku o Lo'e in Kane'ohe Bay, Hawaii. Here, we report the complete genome of Pseudoalteromonas sp. strain OCN003. Copyright © 2015 Beurmann et al.
We have used whole genome paired-end Illumina sequence data to identify tandem duplications in 20 isofemale lines of Drosophila yakuba and 20 isofemale lines of D. simulans and performed genome wide validation with PacBio long molecule sequencing. We identify 1,415 tandem duplications that are segregating in D. yakuba as well as 975 duplications in D. simulans, indicating greater variation in D. yakuba. Additionally, we observe high rates of secondary deletions at duplicated sites, with 8% of duplicated sites in D. simulans and 17% of sites in D. yakuba modified with deletions. These secondary deletions are consistent with the action of…