This gene encodes a PDZ domain-containing protein. PDZ motifs are modular protein-protein interaction domains consisting of 80-120 amino acid residues. PDZ domain-containing proteins interact with each other in cytoskeletal assembly or with other proteins involved in targeting and clustering of membrane proteins. The protein encoded by this gene interacts with alpha-actinin-2 through its N-terminal PDZ domain and with protein kinase C via its C-terminal LIM domains. The LIM domain is a cysteine-rich motif defined by 50-60 amino acids containing two zinc-binding modules. This protein also interacts with all three members of the myozenin family. Mutations in this gene have been associated with myofibrillar myopathy and dilated cardiomyopathy. Alternatively spliced transcript variants encoding different isoforms have been identified; all isoforms have N-terminal PDZ domains while only longer isoforms (1, 2 and 5) have C-terminal LIM domains. [provided by RefSeq, Jan 2010]
Forensic Context
A study in a human patient demonstrated that RNA sequencing of cardiac and skeletal muscle revealed abnormal splicing of the LDB3, specifically the pathogenic inclusion of exon 11, which served as a molecular diagnostic marker for genetically confirmed myotonic dystrophy type 1 and was implicated as a potential mechanism in a case of sudden cardiac death [Yamamoto et al. DOI:10.1016/j.forsciint.2019.109906].