Biology subjects

Detleffsen, J.

Publications and source records attributed to Detleffsen, J..

3 recordsLinked to original sources

bioRxiv2025

SC-Framework: A robust and FAIR semi-interactive environment for single-cell resolution datasets

The accelerated development of single-cell technologies has profoundly impacted the field of biological research, facilitating unparalleled insights into cellular heterogeneity. However, this progress has also produced new computational challenges in the field of bioinformatics: single-cell datasets are increasingly high-dimensional, multimodal, and large-scale, while analysis workflows often remain fragmented, data type specific, ad hoc, and difficult to reproduce. The prevailing methodologies are dependent on a combination of public tools, which hinders the reproducibility of results, limits scalability, and complicates the efforts to establish benchmarks. The necessity for a higher-level, unified framework for single-cell data analysis is paramount to address these inherent limitations. Here, we introduce the SC-Framework, providing the integration of standardized data structures, declarative workflows and standardized computational backends in a containerized environment, enabling analysts to focus on biological interpretation rather than technical overhead. SC-Framework is available at GitHub (https://github.com/loosolab/SC-Framework).

bioinformatics↗

bioRxiv2025

PEAKQC: Periodicity Evaluation in scATAC-seq data for quality assessment

ATAC-seq is a common protocol to identify regulatory regions in the genome. While quality control (QC) standards are well-established for bulk ATAC-seq, application to single-cell ATAC-seq remains challenging due to data sparsity, noise, and a lack of consensus on effective QC metrics and thresholds. Existing methods, such as fragment length ratio offer limited resolution and fail to fully utilize fragment length distribution (FLD) patterns. We present PEAKQC, a Python-based tool designed to assess single-cell ATAC-seq data quality using a wavelet-based convolution of FLD patterns. Benchmarking PEAKQC against established QC metrics demonstrates an overall more consistent, linear quality assessment of ATAC data. PEAKQC improves downstream analyses by effectively filtering low-quality cells while preserving biologically meaningful data. When combined with other metrics, such as the ratio of fragments in peaks and total counts, PEAKQC enhances clustering accuracy and cell-type identification. The tool is modular, easily installable via Python Package Index, and integrates seamlessly into Python-based single-cell analysis frameworks. PEAKQC provides a robust and scalable solution for single-cell ATAC-seq QC, addressing current gaps in the field and suggesting FLD patterns as a new standard for data quality assessment.

bioinformatics↗

bioRxiv2024

flt1 inactivation promotes zebrafish cardiac regeneration by enhancing endothelial activity and limiting the fibrotic response

Summary statementflt1 inactivation promotes zebrafish cardiac regeneration by enhancing coronary revascularization and endocardial expansion, while limiting myofibroblast differentiation. VEGFA administration has been explored as a pro-angiogenic therapy for cardiovascular diseases including heart failure for several years, but with little success. Here we investigate a different approach to augment VEGFA bioavailability: by deleting the VEGFA decoy receptor VEGFR1/FLT1, one can achieve more physiological VEGFA concentrations. We find that following cryoinjury, zebrafish flt1 mutant hearts display enhanced coronary revascularization and endocardial expansion, increased cardiomyocyte dedifferentiation and proliferation, and decreased scarring. Suppressing Vegfa signaling in flt1 mutants abrogates these beneficial effects of flt1 deletion. Transcriptomic analyses of cryoinjured flt1 mutant hearts reveal enhanced endothelial MAPK/ERK signaling and downregulation of the transcription factor gene egr3. Using newly generated genetic tools, we observe egr3 upregulation in the regenerating endocardium, and find that Egr3 promotes myofibroblast differentiation. These data indicate that with enhanced Vegfa bioavailability, the endocardium limits myofibroblast differentiation via egr3 downregulation, thereby providing a more permissive microenvironment for cardiomyocyte replenishment after injury.

molecular biology↗