Biology subjects

Schlapansky, M. F.

Publications and source records attributed to Schlapansky, M. F..

3 recordsLinked to original sources

bioRxiv2025

Cell-stereotyped DNA repair outcomes are widespread during genome editing

Genome editing outcomes are governed by DNA repair pathways that vary with cell type and state. We developed scOUT-seq (single-cell Outcomes Using Transcript sequencing), a scalable approach that jointly profiles transcriptomes and matched multi-allelic editing outcomes ranging from homology directed repair (HDR) to inter-chromosomal translocations. We mapped editing outcomes in human CD34 hematopoietic stem and progenitor cells (HSPCs), mouse LSK HSPC equivalents, human upper airway organoids, and mouse multi-organ in vivo editing. Profiling 500,000 alleles across 74 cell types, scOUT-seq revealed that outcomes in most cell subtypes differ markedly from the bulk average. Various cell types shifted major repair classes, preferred different molecular sequences, and even enriched large structural variants, with distinctive patterns of allelic co-occurrence. Surprisingly, rare stem subtypes diverged from prevalent progenitors, and inhibitory neuron subtypes efficiently incorporated HDR alleles. These data suggest the potential for tailored therapeutic editing that may have been missed by bulk measurements.

genomics↗

bioRxiv2025

WEE1 inhibitors synergise with mRNA translation defects via activation of the kinase GCN2

Inhibitors of the protein kinase WEE1 have emerged as promising agents for cancer therapy. In this study, we uncover synergistic interactions between WEE1 small- molecule inhibitors and defects in mRNA translation, mediated by activation of the integrated stress response (ISR) through the kinase GCN2. Using a pooled CRISPRi screen, we identify GSPT1 and ALKBH8 as factors whose depletion confer hypersensitivity to the WEE1 inhibitor, AZD1775. We demonstrate that this synergy depends on ISR activation, which is induced by the off-target activity of WEE1 inhibitors. Furthermore, PROTAC-based WEE1 inhibitors and molecular glues show reduced or no ISR activation, suggesting potential strategies to minimise off-target toxicity. Our findings reveal that certain WEE1 inhibitors elicit dual toxicity via ISR activation and genotoxic stress, with ISR activation being independent of WEE1 itself or cell-cycle status. This dual mechanism highlights opportunities for combination therapies, such as pairing WEE1 inhibitors with agents targeting the mRNA translation machinery. This study also underscores the need for more precise WEE1 targeting strategies to mitigate off-target effects, with implications for optimising the therapeutic potential of WEE1 inhibitors.

cancer biology↗

bioRxiv2019

Ifnar1 signaling breaks the hepatic urea cycle to regulate adaptive immunity

Infections induce complex host responses linked to antiviral defense, inflammation and tissue damage and repair. These processes are increasingly understood to involve systemic metabolic reprogramming. We hypothesized that the liver as a central metabolic hub may orchestrate many of these changes during infection. Thus, we investigated the systemic interplay between inflammation and metabolism in a mouse model of chronic viral infection and hepatitis. Here we show that virus-induced type I interferon (IFN-I) modulates wide-spread metabolic alterations of the liver in a hepatocyte-intrinsic Ifnar1-dependent way. Specifically, IFN-I repressed the transcription of numerous genes with metabolic function including Otc and Ass1, which encode enzymes of the urea cycle. This led to decreased arginine and increased ornithine concentrations in the circulation, resulting in suppressed virus-specific CD8 T cell responses and ameliorated liver pathology. These findings establish IFN-I-induced modulation of hepatic metabolism and the urea cycle as an endogenous mechanism of immunoregulation.

immunology↗