Biology subjects

Roback, E.

Publications and source records attributed to Roback, E..

3 recordsLinked to original sources

bioRxiv2025

SWIF-TE: identifying novel transposable element insertions from short read data

Transposable element (TE) insertion polymorphisms (TIPs) are TEs not in the same location between individuals. TIPs have contributed to genomic and phenomic variation but have been historically difficult to study due to their repetitive nature. Here, we describe a fast and memory-efficient tool to identify novel TIPs from short read sequences. SWIF-TE was able to identify 1,438 insertions at a precision rate of 27% using 0.10 Gb of memory and 0.82 hours of runtime from 15x resequencing data of a non-reference maize inbred. SWIF-TE is a powerful tool for studying TE variation in species with TE-rich genomes.

bioinformatics↗

bioRxiv2024

Genes Underlying Adaptive Physiological Shifts Among Hibernating Mammals

Hibernation has evolved several times in mammals to overcome harsh winter climates and food scarcity. During hibernation, animals undergo extreme shifts in metabolic rate, heart rate, respiration, and body temperature. These changes reduce energy consumption and allow animals to survive solely on their fat reserves. Understanding the mechanisms for these extreme shifts has long been recognized as a model for translational medicine as hibernators do not exhibit the same adverse effects of extended immobility that non-hibernating mammals suffer. Though work on individual species has illuminated important mechanisms of these functional changes, the genomic basis of this phenotype remains largely unknown, and few studies have drawn on comparative work to elucidate commonalities across diverse hibernating mammals. Synthesizing both single species and comparative approaches, we use metabolomic data from active and denning black bears (Ursus americanus) to guide bioinformatic analyses of genes using tests of selection and evolutionary rate convergence across independent lineages of hibernating mammals. We identify several genes with significant signatures of selection and evolutionary rate convergence in hibernators that represent both previously known and novel genetic mechanisms of the hibernation phenotype. These data provide novel insights into the genetic basis of this adaptation and serve to direct clinical research in hibernation-based therapies.

evolutionary biology↗

bioRxiv2023

Astyanax mexicanus surface and cavefish chromosome-scale assemblies for trait variation discovery

The ability of organisms to adapt to sudden extreme environmental changes produces some of the most drastic examples of rapid phenotypic evolution. The Mexican Tetra, Astyanax mexicanus, is abundant in the surface waters of northeastern Mexico, but repeated colonizations of cave environments have resulted in the independent evolution of troglomorphic phenotypes in several populations. Here, we present three chromosome-scale assemblies of this species, for one surface and two cave populations, enabling the first whole-genome comparisons between independently evolved cave populations to evaluate the genetic basis for the evolution of adaptation to the cave environment. Our assemblies represent the highest quality of sequence completeness with predicted protein-coding and non-coding gene metrics far surpassing prior resources and, to our knowledge, all long-read assembled teleost genomes, including zebrafish. Whole genome synteny alignments show highly conserved gene order among cave forms in contrast to a higher number of chromosomal rearrangements when compared to other phylogenetically close or distant teleost species. By phylogenetically assessing gene orthology across distant branches of amniotes, we discover gene orthogroups unique to A. mexicanus. When compared to a representative surface fish genome, we find a rich amount of structural sequence diversity, defined here as the number and size of insertions and deletions as well as expanding and contracting repeats across cave forms. These new more complete genomic resources ensure higher trait resolution for comparative, functional, developmental, and genetic studies of drastic trait differences within a species.

genomics↗