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Kaulich, M.

Publications and source records attributed to Kaulich, M..

2 recordsLinked to original sources

Integrative analysis of epigenetics data identifies gene-specific regulatory elements

Understanding the complexity of transcriptional regulation is a major goal of computational biology. Because experimental linkage of regulatory sites to genes is challenging, computational methods considering epigenomics data have been proposed to create tissue-specific regulatory maps. However, we showed that these approaches are not well suited to account for the variations of the regulatory landscape between cell-types. To overcome these drawbacks, we developed a new method called SO_SCPCAPTITCHC_SCPCAPIO_SCPCAPTC_SCPCAP, that identifies and links putative regulatory sites to genes. Within SO_SCPCAPTITCHC_SCPCAPIO_SCPCAPTC_SCPCAP, we consider the chromatin accessibility signal of all samples jointly to identify regions exhibiting a signal variation related to the expression of a distinct gene. SO_SCPCAPTITCHC_SCPCAPIO_SCPCAPTC_SCPCAP outperforms previous approaches in various validation experiments and was used with a genome-wide CRISPR-Cas9 screen to prioritize novel doxorubicin-resistance genes and their associated non-coding regulatory regions. We believe that our work paves the way for a more refined understanding of transcriptional regulation at the gene-level.

bioinformatics

Competitive inhibitors of Ras effector binding

The small GTPases H, K and NRas are molecular switches that are indispensable for the correct regulation of cellular proliferation and growth. Mutations in Ras are associated with cancer and result in unwanted activation of signaling processes caused by aberrant recruitment of downstream effector proteins. In this study, we have engineered variants of the Ras-binding domain (RBD) of CRAF kinase that bind with highly improved affinity the effector binding site of Ras. Structural characterization demonstrates how the engineered RBD variants outcompete effector binding and inhibit Ras signaling in cells leading to apoptosis, growth arrest and senescence. The optimized RBD variants provide new insights in Ras biology and enabled the functional stratification of Ras dependency in patient-derived colorectal cancer organoids. One sentence summaryInhibition of effector kinase binding to Ras induces senescence in non-tumorigenic cells and reveals Ras dependency in patient-derived cancer organoids.

cancer biology