Involved in regulating cell migration through association with the actin cytoskeleton. Has an essential role in the maintenance of Z line and sarcomere integrity. Defects in NEXN are the cause of cardiomyopathy dilated type 1CC (CMD1CC). A disorder characterized by ventricular dilation and impaired systolic function, resulting in congestive heart failure and arrhythmia. Patients are at risk of premature death. Defects in NEXN are the cause of familial hypertrophic cardiomyopathy type 20 (CMH20). CMH20 is a hereditary heart disorder characterized by ventricular hypertrophy, which is usually asymmetric and often involves the interventricular septum. The symptoms include dyspnea, syncope, collapse, palpitations, and chest pain. They can be readily provoked by exercise. The disorder has inter- and intrafamilial variability ranging from benign to malignant forms with high risk of cardiac failure and sudden cardiac death. 4 isoforms of the human protein are produced by alternative splicing. Note: This description may include information from UniProtKB.