Cellular integrity plus: organelle-related and protein-targeting functions of intermediate filaments.
Intermediate filament proteins (IFs) maintain cell and tissue integrity, based on evidence of their polymerization and mechanical properties, abundance and disease-associated phenotypes. This 'traditional' function is now augmented by organelle-related and protein-targeting roles. Mitochondrial location and function depend on intact IFs, as demonstrated for desmin, keratins and neurofilaments. Golgi positioning is regulated by several IFs, and endosomal/lysosomal protein distribution by vimentin. IFs dramatically affect nuclear function and shape and play a role in subcellular and membrane targeting of proteins. These functions have been noted in tissues but in some cases only in cell culture. The IF-related organelle-specific and protein-targeting roles, which are likely interrelated, provide functions beyond cell scaffolding and integrity and contribute to the cytoprotective and tissue-specific functions of IF proteins.
Toivola
Diana M
DM
Palo Alto VA Medical Center, 3801 Miranda Avenue, Palo Alto, CA 94304, USA.
Tao
Guo-Zhong
GZ
Habtezion
Aida
A
Liao
Jian
J
Omary
M Bishr
MB
D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D003599:Cytoskeleton / Q000378:metabolism; D011992:Endosomes / Q000378:metabolism; D006056:Golgi Apparatus / Q000378:metabolism; D006801:Humans; D007382:Intermediate Filaments / Q000502:physiology*; D008247:Lysosomes / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism; D008954:Models, Biological; D015388:Organelles / Q000378:metabolism*; D021381:Protein Transport / Q000502:physiology