A novel splice site FUS mutation in a familial ALS case: effects on protein expression. Issue 1 (2nd January 2022)

• Record Type: Journal Article
• Authors: Canosa, Antonio; Lomartire, Annarosa; De Marco, Giovanni; Grassano, Maurizio; Brunetti, Maura; Manera, Umberto; Vasta, Rosario; Salamone, Paolina; Fuda, Giuseppe; Sbaiz, Luca; Gallone, Salvatore; Moglia, Cristina; Calvo, Andrea; Chiò, Adriano
• Is Part Of: Amyotrophic lateral sclerosis and frontotemporal degeneration. Volume 23:Issue 1/2(2022)
• Page Start: 128
• Page End: 136
• Publication Date: 2022-01-02
• Subjects: Amyotrophic lateral sclerosis -- FUS -- splice site mutation -- loss of function; 616.839
• DOI: 10.1080/21678421.2021.1909065
• Languages: English
• ISSNs: 2167-8421

Abstract

Abstract: Objective: To investigate the impact of a novel heterozygous FUS mutation in the acceptor splice site of intron 14 (c.1542 − 1 g > t) on protein expression in Peripheral Blood Mononuclear Cells (PBMC) from a familial ALS patient. Methods : PBMC were isolated for mRNA analysis (cDNA synthesis, sequencing and one-step RT-PCR), Western Immunoblot (WI), and Immunofluorescence (IF). Results : cDNA analysis revealed the skipping of exon 15 and a premature stop codon at c.228. RT-PCR showed reduced FUS mRNA by more than half compared to a healthy control (HC) and an ALS patient without genetic mutations (wtALS). In WI FUS band intensity in the proband was 30–50% compared to HC and wtALS. An antibody expected to detect only the wild-type protein did not reveal any reduction of FUS band intensity compared to the other antibodies. IF showed no difference among HC, wtALS, and the proband. Discussion : The reduction of FUS mRNA and protein in PBMC suggests the absence of the truncated protein, probably due to nonsense-mediated decay, leading to loss of function.