Investigation of Splicing Abnormalities in Prpf8 Mutant Mice and Zebrafish

Abstract

PRPF8 is one of the most evolutionarily conserved proteins. PRPF8 is essential for splicing fidelity, for its role in splicing through its interactions with the spliceosome. PRPF8 mutations have been linked to disease-causing retinitis pigmentosa. Along with that, there is some evidence of other clinical consequences such as cancer, glaucoma, and neurodevelopmental disorders. A novel association between the PRPF8 gene and developmental cardiac defects has been investigated thoroughly by Hentges lab. They reported that during embryonic growth, PRPF8 gene variants have been implicated in affecting cardiac development. This was caused by cilia abnormalities that disturb the formation of the heart. Therefore, this MSc project aims to increase the understanding of PRPF8 splicing regulation by examining the RNAseq data generated in the lab. Alongside Prpf8, two additional genes were indicated as genes of interest following an RNAseq dataset analysis which revealed splicing defects in the genes Dnm1l and Csk. Upon conducting a literature search, variants of the DNM1L gene have been recognized across different species to be linked with cardiomyopathy via mitochondrial dysfunction. However, there is no direct evidence of the association between Csk and cardiomyopathy. Moreover, this project utilized a mix of bioinformatics and experimental validation methods to investigate the significance of the DNM1L and Csk genes, their involvement in cardiac development, as well as the impact of their genetic variants on the splicing process. Moreover, lab experimentation confirmed that Dnm1l has expression in the heart, brain, and E9.5 tissues of Prpf8 mutant mice (K27). However, the Csk expression could not be detected across different tissues. An in-depth investigation into the Dnm1l gene is encouraged to examine the differences in expression across various embryonic stages to assess its impact on the splicing process and investigate the relationship between DNM1L and PRPF8 in relation to the pathogenesis of cardiomyopathy.