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Danner, J.

Publications and source records attributed to Danner, J..

3 recordsLinked to original sources

In vivo selection and glymphatic delivery of AAV5 capsids engineered to target human glial progenitor cells

To establish a means of efficiently transducing human glial progenitor cells (hGPCs) in vivo with therapeutic transgenes, we targeted PDGFRA-driven Cre-recombinase expressing hGPCs in human glial chimeric mice with a library of capsid-modified, recombination-reported adeno-associated viruses (AAVs). PCR screening for gliotropic viral capsid sequences, filtered against visceral organs, identified a set of AAV5-based vectors that preferentially infected human GPCs and/or their derived astrocytes and oligodendrocytes in vivo, with minimal systemic infection. To maximize the intracerebral distribution of these viruses while minimizing their dosing and extracerebral spread, we paired their intracisternal delivery with systemic hypertonicity. This method exploited intracerebral glymphatic flow to bypass the blood-brain barrier, delivering AAV directly into the brain parenchyma. Glymphatic delivery of capsid-modified AAV5s, evolved on human GPCs in vivo, thus enables efficient, brain-wide transgene delivery to human glia and their progenitors in the adult brain, with minimal off-target transduction.

neuroscience↗

A rapid protocol for ribosome profiling of low input samples

Ribosome profiling provides quantitative, comprehensive, and high-resolution snapshots of cellular translation by the high-throughput sequencing of short mRNA fragments that are protected from nucleolytic digestion by ribosomes. While the overall principle is simple, the workflow of ribosome profiling experiments is complex and challenging, and typically requires large amounts of sample, limiting its broad applicability. Here, we present a new protocol for ultra-rapid ribosome profiling from low-input samples. It features a robust strategy for sequencing library preparation within one day that employs solid phase purification of reaction intermediates, allowing to reduce the input to as little as 0.1 pmol of RNA. Hence, it is particularly suited for the analyses of small samples or targeted ribosome profiling. Its high sensitivity and its ease of implementation will foster the generation of higher quality data from small samples, which opens new opportunities in applying ribosome profiling.

systems biology↗

AGO1x prevents dsRNA-induced interferon signaling to promote breast cancer cell proliferation

Initially reported for viral RNA, elongation of polypeptide chains beyond the stop codon (translational readthrough (TR)) also occurs on eukaryotic transcripts. TR diversifies the proteome and can modulate protein levels 1-6. Here we report that AGO1x, a conserved TR isoform of Argonaute 1, is generated in highly proliferative breast cancer cells, where it curbs accumulation of double stranded RNAs, the induction of the interferon response and apoptosis. In contrast to other mammalian Argonaute protein family members with primarily cytoplasmic functions, AGO1x localizes to the nucleus, in the vicinity of nucleoli. We identify a novel interaction of AGO1x with the Polyribonucleotide Nucleotidyltransferase 1, depletion of either protein leading to dsRNA accumulation and impaired cell proliferation. Our study thus uncovers a novel function of an Argonaute protein outside of the miRNA effector pathway, in buffering dsRNA-induced interferon responses. As AGO1x expression is tightly linked to breast cancer cell proliferation, our study suggests a new direction for limiting tumor growth.

cell biology↗