Biology subjects

Berger, M. J.

Publications and source records attributed to Berger, M. J..

5 recordsLinked to original sources

bioRxiv2022

Allele-specific expression reveals genetic drivers of tissue regeneration in mice

In adult mammals, skin wounds typically heal by scarring rather than through regeneration. In contrast, "super-healer" MRL mice have the unusual ability to regenerate ear punch wounds, yet the molecular basis for this regeneration remains elusive. Here, in hybrid crosses between MRL and non-regenerating mice, we use allele-specific gene expression to identify cis-regulatory variation associated with ear regeneration. Analyzing three major wound cell populations, we identified extensive strain- and tissue- specific cis-regulatory divergence associated with differences in healing outcomes. Genes with cis-regulatory differences specifically in fibroblasts were associated with wound healing phenotypes and pathways, and were enriched near genetic markers associated with ear-healing in a genetic cross. Finally, we demonstrated that one of these genes, Cfh, could be applied ectopically to accelerate wound repair and induce regeneration in typically fibrotic wounds. Overall, our results provide insight into the molecular drivers of regeneration in MRL mice with potential clinical implications.

genomics↗

bioRxiv2020

Color Data v2: a user-friendly, open-access database with hereditary cancer and hereditary cardiovascular conditions datasets

Publicly-available genetic databases promote data sharing and fuel scientific discoveries for the prevention, treatment, and management of disease. In 2018, we built Color Data, a user-friendly, open access database containing genotypic and self-reported phenotypic information from 50,000 individuals who were sequenced for 30 genes associated with hereditary cancer. In a continued effort to promote access to these types of data, we launched Color Data v2, an updated version of the Color Data database. This new release includes additional clinical genetic testing results from more than 18,000 individuals who were sequenced for 30 genes associated with hereditary cardiovascular conditions, as well as polygenic risk scores for breast cancer, coronary artery disease, and atrial fibrillation. In addition, we used self-reported phenotypic information to implement the following four clinical risk models: Gail Model for five-year risk of breast cancer, Claus Model for lifetime risk of breast cancer, simple office-based Framingham Coronary Heart Disease Risk Score for ten-year risk of coronary heart disease, and CHARGE-AF simple score for five-year risk of atrial fibrillation. These new features and capabilities are highlighted through two sample queries in the database. We hope that the broad dissemination of this data will help researchers continue to explore genotype-phenotype correlations and identify novel variants for functional analysis, enabling scientific discoveries in the field of population genomics. Database URL: https://data.color.com/

genetics↗

bioRxiv2019

Single-cell transcriptional diversity is a hallmark of developmental potential

Single-cell RNA-sequencing (scRNA-seq) is a powerful approach for reconstructing cellular differentiation trajectories. However, inferring both the state and direction of differentiation without prior knowledge has remained challenging. Here we describe a simple yet robust determinant of developmental potential--the number of detectably expressed genes per cell-- and leverage this measure of transcriptional diversity to develop a new framework for predicting ordered differentiation states from scRNA-seq data. When evaluated on ~150,000 single-cell transcriptomes spanning 53 lineages and five species, our approach, called CytoTRACE, outperformed previous methods and ~19,000 molecular signatures for resolving experimentally-confirmed developmental trajectories. In addition, it enabled unbiased identification of tissue-resident stem cells, including cells with long-term regenerative potential. When used to analyze human breast tumors, we discovered candidate genes associated with less-differentiated luminal progenitor cells and validated GULP1 as a novel gene involved in tumorigenesis. Our study establishes a key RNA-based correlate of developmental potential and provides a new platform for robust delineation of cellular hierarchies (https://cytotrace.stanford.edu).

genomics↗

bioRxiv2017

Independent erosion of conserved transcription factor binding sites points to shared hindlimb, vision, and scrotum loss in different mammals

Genetic variation in cis-regulatory elements is thought to be a major driving force in morphological and physiological change. However, identifying transcription factor binding events which code for complex traits remains a challenge, motivating novel means of detecting putatively important binding events. Using a curated set of 1,154 high-quality transcription factor motifs, we demonstrate that independently eroded binding sites are enriched for independently lost traits in three distinct pairs of placental mammals. We show that these independently eroded events pinpoint the loss of hindlimbs in dolphin and manatee, degradation of vision in naked mole-rat and star-nosed mole, and the loss of scrotum in white rhinoceros and Weddell seal. Our study exhibits a novel methodology to detect cis-regulatory mutations which help explain a portion of the molecular mechanism underlying complex trait formation and loss.\n\nAuthor SummaryEvolution has produced an astounding variety of species with incredibly diverse phenotypes. A central question in evolutionary developmental biology is how (and which) DNA evolves to encode all of these different traits. A prevailing hypothesis is that changes in regulatory DNA, short stretches of DNA which control the expression of protein-coding genes, drive important differences in trait formation between species. The basic building block of regulatory DNA is thought to be transcription factor binding sites, shortl genomic sequences which attract proteins whose central role is to control the rate of transcription. In this study, we asked whether the independent erosion of otherwise highly conserved transcription factor binding sites points to a trait shared between species which have undergone similar adaptations. We show that our method is able to point to the loss of hindlimbs in dolphin and manatee, poor vision in naked mole-rat and star-nosed mole, and loss of scrotum in Weddell seal and white rhinoceros. Overall, our study exhibits a means of detecting evolutionarily important genomic regions which help explain a portion of complex trait loss and retention.

evolutionary biology↗

bioRxiv2017

Comment on "A genetic signature of the evolution of loss of flight in the Galapagos cormorant"

Burga et al. could not identify gene regulatory regions which might contribute to flightlessness in the Galapagos cormorant. Using a bird-specific alignment we discover 48 limb enhancers showing strong accelerated evolution in P. harrisi, including enhancers of key cilia development, hedgehog signaling, and planar cell polarity genes, such as Prickle1, Twist2 and Ndk1, extending Burga's proposed mechanism into the non-coding genome.

genomics↗