Gene:  Plec, Mouse

Plectin is a prominent member of an important family of structurally and in part functionally related proteins termed plakins or cytolinkers that are capable of interlinking different elements of the cytoskeleton. Plakins with their multi-domain structure and enormous size not only play crucial roles in maintaining cell and tissue integrity and orchestrating dynamic changes in cytoarchitecture and cell shape but also serve as scaffolding platforms for the assembly positioning and regulation of signaling complexes (reviewed in PMID: 9701547 11854008 17499243). Plectin is expressed as several protein isoforms in a wide range of cell types and tissues from a single gene located on chromosome 8 in humans (PMID: 8633055 8698233). Until 2010 this locus was named plectin 1 (symbol PLEC1 in human; Plec1 in mouse and rat) and the gene product had been referred to as "hemidesmosomal protein 1" or "plectin 1 intermediate filament binding 500kDa". These names were superseded by plectin. The plectin gene locus in mouse on chromosome 15 has been analyzed in detail (PMID: 10556294 14559777) revealing a genomic exon-intron organization with well over 40 exons spanning over 62 kb and an unusual 5' transcript complexity of plectin isoforms. Eleven exons (1-1j) have been identified that alternatively splice directly into a common exon 2 which is the first exon to encode plectin's highly conserved actin binding domain (ABD). Three additional exons (-1 0a and 0) splice into an alternative first coding exon (1c) and two additional exons (2alpha and 3alpha) are optionally spliced within the exons encoding the acting binding domain (exons 2-8). Analysis of the human locus has identified eight of the eleven alternative 5' exons found in mouse and rat (PMID: 14672974); exons 1i 1j and 1h have not been confirmed in human. Furthermore isoforms lacking the central rod domain encoded by exon 31 have been detected in mouse (PMID:10556294) rat (PMID: 9177781) and human (PMID: 11441066 10780662 20052759). It has been shown that the short alternative amino-terminal sequences encoded by the different first exons direct the targeting of the various isoforms to distinct subcellular locations (PMID: 14559777). As the expression of specific plectin isoforms was found to be dependent on cell type (tissue) and stage of development (PMID: 10556294 12542521 17389230) it appears that each cell type (tissue) contains a unique set (proportion and composition) of plectin isoforms as if custom-made for specific requirements of the particular cells. Concordantly individual isoforms were found to carry out distinct and specific functions (PMID: 14559777 12542521 18541706). In 1996 a number of groups reported that patients suffering from epidermolysis bullosa simplex with muscular dystrophy (EBS-MD) lacked plectin expression in skin and muscle tissues due to defects in the plectin gene (PMID: 8698233 8941634 8636409 8894687 8696340). Two other subtypes of plectin-related EBS have been described: EBS-pyloric atresia (PA) and EBS-Ogna. For reviews of plectin-related diseases see PMID: 15810881 19945614. Mutations in the plectin gene related to human diseases should be named based on the position in NM_000445 (human variant 1 isoform 1c) unless the mutation is located within one of the other alternative first exons in which case the position in the respective Reference Sequence should be used. [provided by RefSeq Aug 2011]

• Cytoskeleton remodeling - Keratin filaments
• Cytoskeleton remodeling - Neurofilaments