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Nelson, J. W.

Publications and source records attributed to Nelson, J. W..

3 recordsLinked to original sources

Inhibition of methylthioadenosine phosphorylase provides protection from experimental acute kidney injury

Acute kidney injury (AKI) increases mortality risk and predisposes individuals to chronic kidney disease. Metabolic pathways play a crucial role in AKI pathophysiology. Here, we investigate the potential of methylthioadenosine phosphorylase (MTAP) inhibition as a novel renoprotective strategy in AKI. Using AKI mouse models, we demonstrate that a small molecule MTAP inhibitor significantly reduces kidney injury markers and improves renal histology. RNA sequencing reveals that MTAP inhibition modulates pathways associated with inflammation, oxidative phosphorylation, and cell survival. Additionally, analysis of human single-cell RNA sequencing data links MTAP expression to kidney injury marker in AKI. This study provides evidence of MTAP inhibition as a potential therapeutic strategy for AKI, highlighting metabolic dysregulation as a target for future clinical interventions.

pathology↗

Enriched Single-Nucleus RNA-Sequencing reveals unique attributes of distal convoluted tubule cells

BackgroundThe distal convoluted tubule (DCT) comprises two subsegments, DCT1 and DCT2, with different functional and molecular characteristics. The functional and molecular distinction between these segments, however, has been controversial. MethodsTo understand the heterogeneity within the DCT population with better clarity, we enriched for DCT nuclei by using a mouse line combining "Isolation of Nuclei TAgged in specific Cell Types" and NCC (sodium chloride cotransporter)-driven inducible Cre recombinase. We sorted the fluorescently labeled DCT nuclei using Fluorescence-Activated Nucleus Sorting, and performed single nucleus transcriptomics. ResultsAmong 25,183 DCT cells, 70% were from DCT1 and 30% from DCT2. Additionally, there was a small population (<1%) enriched in proliferation-related genes, such asTop2a, Cenpp, and Mki67. Both DCT1 and DCT2 express NCC, magnesium transport genes are more abundant along DCT1; whereas calcium, electrogenic sodium and potassium transport genes are more abundant along DCT2. The transition between these two segments are gradual with a transitional zone where DCT1 and DCT2 cells are interspersed. The expression of the homeobox genes is not consistent between all DCT cells, suggesting that they develop along different trajectories. ConclusionTranscriptomics analysis of an enriched rare cell population using genetically targeted approach offers better clarification of the function and classification. The DCT segment is short, yet, can be separated into two sub-types that serve distinct functions, and are speculated to derive from different origins during development. Significance StatementHigh-resolution snRNAseq data indicate a clear separation between primary sites of calcium and magnesium handling within DCT. Both DCT1 and DCT2 express Slc12a3, but these subsegments serve distinctive functions, with more abundant magnesium handling genes along DCT1 and more calcium handling genes along DCT2. The data also provides insight into the plasticity of the distal nephron-collecting duct junction, formed from cells of separate embryonic origins. By focusing/changing gradients of gene expression, the DCT can morph into different physiological cell states on demand.

physiology↗

De novo design of ACE2 protein decoys to neutralize SARS-CoV-2

There is an urgent need for the ability to rapidly develop effective countermeasures for emerging biological threats, such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes the ongoing coronavirus disease 2019 (COVID-19) pandemic. We have developed a generalized computational design strategy to rapidly engineer de novo proteins that precisely recapitulate the protein surface targeted by biological agents, like viruses, to gain entry into cells. The designed proteins act as decoys that block cellular entry and aim to be resilient to viral mutational escape. Using our novel platform, in less than ten weeks, we engineered, validated, and optimized de novo protein decoys of human angiotensin-converting enzyme 2 (hACE2), the membrane-associated protein that SARS-CoV-2 exploits to infect cells. Our optimized designs are hyperstable de novo proteins ([~]18-37 kDa), have high affinity for the SARS-CoV-2 receptor binding domain (RBD) and can potently inhibit the virus infection and replication in vitro. Future refinements to our strategy can enable the rapid development of other therapeutic de novo protein decoys, not limited to neutralizing viruses, but to combat any agent that explicitly interacts with cell surface proteins to cause disease.

biochemistry↗