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Moye, A. L.

Publications and source records attributed to Moye, A. L..

4 recordsLinked to original sources

Airway injury induces alveolar epithelial and mesenchymal responses mediated by macrophages

Airway injury activates local progenitors and stimulates cell-cell interactions to restore homeostasis, but it is unknown how distal niches are impacted. We utilized mouse models of airway-specific epithelial injury to examine secondary tissue-wide alveolar and immune responses. Single-cell transcriptomics and in vivo validation of mouse models of airway-specific epithelial injury revealed transient, tissue-wide proliferation of alveolar type 2 (AT2) progenitor cells after club cell-specific injury or ablation. Myeloid cells exhibited altered gene expression after club cell loss and were detectable in the bronchoalveolar lavage fluid. The AT2 cell proliferative response was reliant on alveolar macrophages (AMs) exhibiting an injury-induced gene expression program. Overall, these results demonstrate that acute airway damage can trigger myeloid-mediated lung alveolar responses that may contribute to disease susceptibility or dysfunction.

cell biology↗

Early-stage lung adenocarcinoma is driven by an injury-associated, plastic cell state dependent on a KRAS-ITGA3-SRC axis

Glycine 12 mutations in the GTPase KRAS (KRASG12) are a known initiating event for lung adenocarcinoma (LUAD) with broad clinical relevance. KRASG12 mutations promote cell-intrinsic rewiring of the lung alveolar type II progenitor (AT2) cells, but to what extent such changes interplay with pathways essential for lung homeostasis and cell fate is unclear. We used single-cell RNA-seq (scRNA-seq) from AT2-mesenchyme organoid co-cultures, mouse models, and stage IA LUAD patient samples to identify conserved regulators of AT2 cell transcriptional dynamics and the impact of KRASG12D with temporal resolution. In AT2WT organoids, a transient injury/plasticity state preceded AT2 self-renewal and AT1 differentiation. Early-stage AT2KRAS cells exhibited perturbed gene expression dynamics most noted by retention of the injury/plasticity state. At later time points in tumorigenesis, AT2KRAS cells consisted of heterogeneous populations that could be defined by either the injury state or high expression of an AT2 cell signature. The injury state in AT2KRAS cells of LUAD in patients, mice, and organoids was distinguishable from AT2WT states by altered receptor expression, including co-expression of ITGA3 and SRC. The combination of clinically relevant KRASG12D and SRC inhibitors to target the oncogenic injury cell state impaired AT2KRAS organoid growth. Thus, an injury/plasticity signature characterized as an essential step in lung repair is used during alveolar cell self-renewal and during initiation and progression of LUAD. Early-stage lung cancer may be susceptible to intervention by targeting the oncogenic-specific nature of this cell state.

cancer biology↗

COOBoostR: an extreme gradient boosting-based tool for robust tissue or cell-of-origin prediction of tumors

We here present COOBoostR (https://github.com/SWJ9385/COOBoostR), a computational method designed for the putative prediction of tissue-or cell-of-origin of various cancer types. COOBoostR leverages regional somatic mutation density information and chromatin mark features to be applied to an extreme gradient boosting-based machine-learning algorithm. COOBoostR ranks chromatin marks from various tissue and cell types which best explain the somatic mutation density landscape of any sample of interest. Through integrating either ChIP-seq based chromatin data or bulk/single cell chromatin accessibility data along with regional somatic mutation density data derived from normal cells/tissue, precancerous lesions, and cancer types, we show that COOBoostR outperforms existing random forest-based methods in prediction speed with comparable or better tissue or cell-of-origin prediction performance. In addition, our results suggest a dynamic somatic mutation accumulation at the normal tissue or cell stage which could be intertwined with the changes in open chromatin marks and enhancer sites. These results further represent chromatin marks shaping the somatic mutation landscape at the early stage of mutation accumulation, possibly even before the initiation of precancerous lesions or neoplasia.

bioinformatics↗

A mechanism for the extension and unfolding of parallel telomeric G-quadruplexes by human telomerase at single-molecule resolution

Telomeric G-quadruplexes (G4) were long believed to form a protective structure at telomeres, preventing their extension by the ribonucleoprotein telomerase. Contrary to this belief, we have previously demonstrated that parallel-stranded conformations of telomeric G4 can be extended by human and ciliate telomerase. However, a mechanistic understanding of the interaction of telomerase with structured DNA remained elusive. Here, we use single-molecule fluorescence resonance energy transfer (smFRET) microscopy and bulk-phase enzymology to propose a mechanism for the resolution and extension of parallel G4 by telomerase. Binding is initiated by the RNA template of telomerase interacting with the G-quadruplex; nucleotide addition then proceeds to the end of the RNA template. It is only through the large conformational change of translocation following synthesis that the G-quadruplex structure is completely unfolded to a linear product. Surprisingly, parallel G4 stabilization with either small molecule ligands or by chemical modification does not always inhibit G4 unfolding and extension by telomerase. These data reveal that telomerase is a parallel G-quadruplex resolvase.

biochemistry↗