Generation of a NRAP-overexpressing mutant from a human iPSC line.

Cardiomyopathies are a major contributor to cardiovascular mortality and are frequently linked to abnormalities in intercalated discs, which coordinate mechanical and electrical signaling between cardiomyocytes. The Nebulin-Related Anchoring Protein (NRAP), a key component of these structures, is essential for myofibril formation and force transmission. In various cardiac diseases such as cardiomyopathies with differing genetic mutations, NRAP protein abundance is increased, yet the functional consequences of this expression change remain insufficiently characterized. To investigate the outcome of NRAP-overexpression (NRAP-OE) on cardiac development and disease, we established a human induced pluripotent stem cell (hiPSC) line with stable and specific NRAP-OE in cardiomyocytes using CRISPR-Cas9-based genome editing. The resulting line was rigorously validated for chromosomal integrity, pluripotency markers, absence of off-target effects and mycoplasma contamination, as well as its capacity for trilineage differentiation. This NRAP-OE model offers a novel platform for investigating how increased NRAP levels influence cardiomyocyte structure and function, and may provide insight into its role in the pathogenesis of cardiomyopathy.