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%0 Thesis
%A Groten, Natalie
%T Auswirkung einer bislang unbekannten Deletionsmutation des Spleißfaktors SRRM4 auf die Synthese der neuronalen Isoform von Protrudin
%I Rheinisch-Westfälische Technische Hochschule Aachen
%V Dissertation
%C Aachen
%M RWTH-2025-08691
%P 1 Online-Ressource : Illustrationen
%D 2025
%Z Veröffentlicht auf dem Publikationsserver der RWTH Aachen University
%Z Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2025
%X This dissertation deals with the case of a patient with a neuronal developmental disorder of unclear origin. In the genetic analysis, a variant in the SRRM4 gene was identified through Whole Exome Sequencing, which was bioinformatically assessed as potentially disease-causing. This mutation occurs in the splice donor sequence behind exon 5 and leads to a complete deletion of this exon at the mRNA level. SRRM4 is a neuronal splice factor that regulates the inclusion of various microexons in mRNA through alternative splicing, allowing for the formation of specific neuronal protein isoforms. In the case of the membrane protein Protrudin/ZFYVE27, SRRM4 dysfunction results in the inability to include the microexon L, which characterizes the neuronal isoform, in the mRNA. The absence of the neuronal Protrudin isoform has been shown in mouse models to impair neurogenesis in previous studies. The aim of this work was to further assess the impact of exon 5 deletion on the functionality of the splice factor SRRM4 through molecular and cell biological methods. Experimentally, the SRRM4-supported Protrudin-L production in HeLa cells was measured as a marker of splicing function, using qPCR quantification. The retention of microexon L in ZFYVE27 transcripts was observed separately for wild-type SRRM4 and SRRM4_del.The results showed no reduced amount of Protrudin-L in cells with the SRRM4_del construct compared to wild-type, indicating that the mutated splice factor appears to function normally. The deletion of exon 5 does not seem to cause a pathogenic dysfunction. Therefore, the patient's phenotype cannot be sufficiently explained by the SRRM4 mutation investigated in this study. However, further experiments, such as those on neurons, could in the future provide a better replication of neuronal splicing, potentially leading to a revision of the mutation's pathogenic assessment.
%F PUB:(DE-HGF)11
%9 Dissertation / PhD Thesis
%R 10.18154/RWTH-2025-08691
%U https://publications.rwth-aachen.de/record/1019979