Genetic and functional analysis of ZMIZ1 in neurodevelopmental disorder with dysmorphic facies and distal skeletal anomalies (NEDDFSA): insights from muscle cells and signaling pathways.

backgroundMutations in the ZMIZ1 gene have been implicated in neurodevelopmental disorder with dysmorphic facies and distal skeletal anomalies (NEDDFSA). However, the underlying cellular and physiological mechanisms remain poorly understood.

methodsExome sequencing was performed to identify candidate variants. qPCR, Western blot, immunofluorescence, CCK-8, and wound-healing assays were employed to assess gene function in human skeletal muscle cells (HSkMCs). RNA-seq and co-immunoprecipitation coupled with mass spectrometry (Co-IP/MS) were used for transcriptomic and interactome profiling.

resultsHere, we identified a novel de novo missense variant c.910G>C (p.A304P) in ZMIZ1 in a patient with NEDDFSA. The p.A304P variant significantly increased ZMIZ1 mRNA and protein expression levels and altered its subcellular localization. Functional assays demonstrated enhanced proliferation and migration in HSkMCs expressing the mutant ZMIZ1. qPCR validation revealed significant dysregulation of key genes in the TGF-β1 signaling pathway. Transcriptome analysis identified the cytokine-cytokine receptor interaction pathway as the most significantly enriched pathway. Additionally, we identified a novel interaction between ZMIZ1 and the transcription factor GTF2I.

conclusionOur study identifies a novel likely pathogenic variant in ZMIZ1 associated with NEDDFSA. These findings provide new insights into the cellular and physiological mechanisms underlying NEDDFSA, highlighting ZMIZ1's role as a regulatory hub in multiple signaling pathways. IMPACT: Our study identifies a novel likely pathogenic variant in the ZMIZ1 gene associated with NEDDFSA, the second in China, and demonstrates its functional impact on cellular processes and signaling pathways, particularly in muscle cells. This finding expands the known ZMIZ1 mutation spectrum and provides the first functional evidence of its role in muscle cells, highlighting its potential as a regulatory hub in multiple pathways beyond the nervous system. These results offer new insights into the cellular mechanisms underlying NEDDFSA, especially in non-neurological tissues, and may facilitate the development of targeted therapies for related disorders.