Login processing...

Trial ends in Request Full Access Tell Your Colleague About Jove

25.5: Cytoskeletal Linker Proteins - Plakins

JoVE Core
Cell Biology

A subscription to JoVE is required to view this content. Sign in or start your free trial.

Cytoskeletal Linker Proteins - Plakins

25.5: Cytoskeletal Linker Proteins - Plakins

Plakins are large proteins with binding domains for microtubules, microfilaments, intermediate filaments, and membrane-associated protein complexes at cell junctions. Plakin functions are evolutionarily conserved and are primarily involved in organizing the different components of the cytoskeleton by crosslinking them to each other and connecting them to the cell-matrix and cell adhesion complexes. They are also known to interact with signal transducers, serve as scaffolds for signaling complexes and modulate vesicle trafficking.

Plakins were initially found associated with intermediate filaments in desmosomes and hemidesmosomes, which are cell junctions in the epithelial tissues.  Therefore, their function was believed to be restricted to maintaining epithelial tissue integrity. However, recent research has resulted in the discovery of new plakins with unique isoforms that arise through the alternative splicing of the plakin gene locus. These isoforms show tissue-specific expression profiles and have unique domain organizations and functions. These isoforms can also associate with the other cytoskeletal filaments and are functional in non-epithelial cells. For example, research on mice and invertebrates has demonstrated the role of plakins in non-epidermal cells such as neurons.

Disorders associated with Plakins

Plakins are cytolinkers crucial to cellular development and maintenance of tissue integrity. Therefore, any defect in the gene coding for plakin can result in various diseases that affect the skin, neuronal tissue, and cardiac and skeletal muscle. Mammals have seven proteins belonging to the plakins, such as desmoplakin, envoplakin, epiplakin, bullous pemphigoid antigen 1, microtubule‐actin crosslinking factor 1, periplakin, and plectin.  In humans, mutations in any of these plakin genes result in disorders of the skin and muscular system. For example, mutations in genes coding for plectin result in a disease called epidermolysis bullosa simplex with muscular dystrophy, which results in fragile skin easily prone to blistering and damage and weakening of muscles over time.

Suggested Reading


Cytoskeletal Linker Proteins Plakins Microtubules Microfilaments Intermediate Filaments Membrane-associated Protein Complexes Cell Junctions Cytoskeleton Organization Crosslinking Cell-matrix Cell Adhesion Complexes Signal Transducers Scaffolds For Signaling Complexes Vesicle Trafficking Desmosomes Hemidesmosomes Epithelial Tissues Alternative Splicing Tissue-specific Expression Profiles Isoforms Non-epithelial Cells Disorders Associated With Plakins

Get cutting-edge science videos from JoVE sent straight to your inbox every month.

Waiting X
Simple Hit Counter