Robert Atkinson, Maria Georgiou, Chunbo Yang, Katarzyna Szymanska, Albert Lahat, Elton J R Vasconcelos, Yanlong Ji, Marina Moya Molina, Joseph Collin, Rachel Queen, Birthe Dorgau, Avril Watson, Marzena Kurzawa-Akanbi, Ross Laws, Abhijit Saxena, Chia Shyan Beh, Chileleko Siachisumo, Franziska Goertler, Magdalena Karwatka, Tracey Davey, Chris F Inglehearn, Martin McKibbin, Reinhard Lührmann, David H Steel, David J Elliott, Lyle Armstrong, Henning Urlaub, Robin R Ali, Sushma-Nagaraja Grellscheid, Colin A Johnson, Sina Mozaffari-Jovin, Majlinda Lako
The carboxy-terminus of the spliceosomal protein PRPF8, which regulates the RNA helicase Brr2, is a hotspot for mutations causing retinitis pigmentosa-type 13, with unclear role in human splicing and tissue-specificity mechanism. We used patient induced pluripotent stem cells-derived cells, carrying the heterozygous PRPF8 c.6926 A > C (p.H2309P) mutation to demonstrate retinal-specific endophenotypes comprising photoreceptor loss, apical-basal polarity and ciliary defects. Comprehensive molecular, transcriptomic, and proteomic analyses revealed a role of the PRPF8/Brr2 regulation in 5'-splice site (5'SS) selection by spliceosomes, for which disruption impaired alternative splicing and weak/suboptimal 5'SS selection, and enhanced cryptic splicing, predominantly in ciliary and retinal-specific transcripts...
April 11, 2024: Nature Communications