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Davenport, K.

Publications and source records attributed to Davenport, K..

4 recordsLinked to original sources

Mesenchymal-epithelial transition serves to rapidly, yet transiently, restore the endometrial epithelium during postpartum murine uterine regeneration

The uterus is a remarkable organ in its ability to undergo extensive tissue damage during menstruation and parturition, yet achieves efficient, scar-free repair. Coordinated regulation of this regenerative process is essential for uterine homeostasis and fertility; however, the underlying mechanisms remain incompletely understood. Here, we demonstrate that mesenchymal-epithelial transition (MET) contributed to postpartum endometrial re-epithelialization using PdgfrCreERT2/+; Rosa26-tdTomatofl/+ lineage tracing mice. Flow cytometry revealed a marked increase in mesenchymal-derived (MD) epithelial cells during active tissue repair. Notably, these cells were transient, undergoing clearance primarily via apoptosis following completed epithelial restoration. We also identified a migratory population of transitional cells of mesenchymal origin within the mesometrial stroma that incorporated into the luminal epithelium, consistent with an active MET program. Single-nucleus RNA sequencing (snRNA-seq) revealed that MD epithelial cells exhibited gene expression profiles associated with cell adhesion and cytoskeletal remodeling, while transitional cells were enriched for genes involved in junctional assembly and actin dynamics. MET-associated genes were significantly upregulated in both transitional and MD epithelial populations. Cell-cell communication analysis highlighted WNT, BMP, and EPHA signaling as candidate regulators of MET during regeneration. Together, these findings provide confirmation of MET as a physiologic mechanism of postpartum endometrial epithelial repair and uncover a coordinated signaling network that facilitates this process. Perturbations in MET may contribute to pathologies such as endometriosis or endometrial cancer, underscoring the importance of understanding mesenchymal-epithelial plasticity in both normal and disease states. SignificanceThe mammalian endometrium undergoes repeated injury and repair during menstruation (women) and pregnancy (most eutherians), yet exhibits a remarkable capacity for rapid, scar-free healing that mediates infection, inflammation and hemorrhage. Despite its clinical relevance, the molecular regulation of endometrial regeneration remains poorly defined. Using a transgenic lineage-tracing mouse model, we identified mesenchymal-derived (MD) epithelial and transitional cells during the regenerative window and revealed a critical role for mesenchymal-epithelial transition (MET) in this process. Single-nucleus RNA sequencing further uncovered functional characteristics of these cells and highlighted WNT, BMP, and EPHA signaling as potential regulators of MET. These findings provide new insight into the cellular and molecular framework of endometrial regeneration and have important implications for diseases involving aberrant tissue repair.

physiology↗

Functional genomics of cattle through integration of multi-omics data

Functional annotation of the bovine genome was performed by characterizing the spectrum of RNA transcription using a multi-omics approach, combining long- and short-read transcript sequencing and orthogonal data to identify promoters and enhancers and to determine boundaries of open chromatin. A total number of 171,985 unique transcripts (50% protein-coding) representing 35,150 unique genes (64% protein-coding) were identified across tissues. Among them, 159,033 transcripts (92% of the total) were structurally validated by independent datasets such as PacBio Iso-seq, ONT-seq, de novo assembled transcripts from RNA-seq, or Ensembl and NCBI gene sets. In addition, all transcripts were supported by extensive independent data from different technologies such as WTTS-seq, RAMPAGE, ChIP-seq, and ATAC-seq. A large proportion of identified transcripts (69%) were novel, of which 87% were produced by known genes and 13% by novel genes. A median of two 5 untranslated regions was detected per gene, an increase from Ensembl and NCBI annotations (single). Around 50% of protein-coding genes in each tissue were bifunctional and transcribed both coding and noncoding isoforms. Furthermore, we identified 3,744 genes that functioned as non-coding genes in fetal tissues, but as protein coding genes in adult tissues. Our new bovine genome annotation extended more than 11,000 known gene borders compared to Ensembl or NCBI annotations. The resulting bovine transcriptome was integrated with publicly available QTL data to study tissue-tissue interconnection involved in different traits and construct the first bovine trait similarity network. These validated results show significant improvement over current bovine genome annotations.

bioinformatics↗

A contiguous de novo genome assembly of sugar beet EL10 (Beta vulgaris L.)

A contiguous assembly of the inbred EL10 sugar beet (Beta vulgaris ssp. vulgaris) genome was constructed using PacBio long read sequencing, BioNano optical mapping, Hi-C scaffolding, and Illumina short read error correction. The EL10.1 assembly was 540 Mb, of which 96.7% was contained in nine chromosome-sized pseudomolecules with lengths from 52 to 65 Mb, and 31 contigs with a median size of 282 kb that remained unassembled. Gene annotation incorporating RNAseq data and curated sequences via the MAKER annotation pipeline generated 24,255 gene models. Results indicated that the EL10.1 genome assembly is a contiguous genome assembly highly congruent with the published sugar beet reference genome. Gross duplicate gene analyses of EL10.1 revealed little large-scale intra-genome duplication. Reduced gene copy number for well-annotated gene families relative to other core eudicots was observed, especially for transcription factors. Variation in genome size in B. vulgaris was investigated by flow cytometry among 50 individuals drawn from EL10 progeny and three unrelated germplasm accessions, producing estimates from 633 to 875 Mb/1C. Read depth mapping with short-read whole genome sequences from other sugar beet germplasm suggested that relatively few regions of the sugar beet genome appeared associated with high-copy number variation.

genomics↗

Exploiting oxalotrophic bacteria to control Aspergillus niger lung infections

Aspergillus fungi are opportunistic pathogens that affect a large number of people worldwide. Many aspects of Aspergillus spp. pathogenesis toward humans are known, but their ability to enhance their infectious potential by manipulating the environmental pH of its host has not been considered yet. In this study, we tested the hypothesis that by producing oxalic acid, Aspergillus niger can manipulate pH during lung infection and thus, interfering with this process could limit pathogenicity. To test this hypothesis, we co-cultured A. niger with oxalotrophic bacteria in increasingly complex testing systems (Petri dishes and 3D-cell cultures systems). In in vitro tests, oxalotrophic bacteria limit oxalic acid production and suppressed the pH shift induced by A. niger. In 3D-cell cultures (Transwells(R) and Bronchioles-on-a-chip), A. niger also modified pH, Ca2+ and oxalic acid concentrations. Co-inoculation with as little as 10 cells of the oxalatrophic bacterium strongly inhibited the germination and development of A. niger and returned each of the three parameters to the baseline physiological values of uninfected cells. This biocontrol interaction between oxalotrophic bacteria and oxalate-producing A. niger could represent a paradigm shift in the fight against opportunistic fungal pathogens, where the host environment is rendered less permissive to fungal development.

microbiology↗