Project description:Western blotting (WB) is widely used to test antibody specificity, but the assay has low throughput and precision. Here we show that an inverted version of WB allows parallel readout with antibody arrays, shotgun mass spectrometry (MS) and immunoprecipitation followed by MS (IP-MS). The pipeline provides means for large-scale implementation of concepts proposed by an international working group on antibody validation (IWGAV).
Project description:Purpose: Hirschsprung’s disease (HSCR, OMIM 142623) represents one of the main causes of neonatal intestinal obstruction. It is caused by dysfunction of neural crest cells (NCCs) and their progeny during development of the enteric nervous system (ENS). HSCR is considered a multifactorial disorder, however, associated risk genes only account for a minority of cases. Consequently, defining disease-relevant variants is still a demanding task. Methods: To reduce the number of candidate genes identified by Whole Exome Sequencing (WES) and to examine their disease-causing relevance, we established a complementary study pipeline including transcriptome data of murine embryonic ENS-relevant tissues, literature and database searches, in silico network analyses as well as functional assays using genome-edited candidate-specific cell clones. Results: Applying this strategy on a pilot set of two HSCR patients and their non-affected parents led to the identification of four novel HSCR candidate genes: ATP7A, SREBF1, ABCD1 and PIAS2. This candidate gene selection was corroborated by the discovery of further rare variants in additional HSCR cases. Moreover, expression analyses revealed that all four genes are expressed in embryonic murine gastrointestinal tissues. Functional analyses using candidate gene-specific, neuronal-like CRISPR/Cas9-edited knockout cell clones demonstrated impaired differentiation, proliferation and/or cell survival capacity. Conclusions: Taken together, the presented study pipeline was proven to be suitable for the selection and validation of candidate genes as well as to gain insight into underlying pathomechanisms of HSCR.
Project description:Ion Torrent based multi-gene sequencing as a reliable diagnostic assay for the detection of somatic mutations in tumors using minimal DNA amounts from FFPE material - validation study