Editing Cytoskeleton (section)

===Intermediate filaments===
{{main|Intermediate filament}}
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Intermediate filaments are a part of the cytoskeleton of many [[Eukaryote|eukaryotic]] cells. These filaments, averaging 10 nanometers in diameter, are more stable (strongly bound) than microfilaments, and heterogeneous constituents of the cytoskeleton. Like [[actin]] filaments, they function in the maintenance of cell-shape by bearing tension ([[microtubules]], by contrast, resist compression but can also bear tension during [[mitosis]] and during the positioning of the centrosome). Intermediate filaments organize the internal tridimensional structure of the cell, anchoring [[organelle]]s and serving as structural components of the [[nuclear lamina]]. They also participate in some cell-cell and cell-matrix junctions. [[Nuclear lamina]] exist in all animals and all tissues. Some animals like the [[drosophila melanogaster|fruit fly]] do not have any cytoplasmic intermediate filaments. In those animals that express cytoplasmic intermediate filaments, these are tissue specific.<ref name="Herrmann">{{cite journal | vauthors = Herrmann H, Bär H, Kreplak L, Strelkov SV, Aebi U | title = Intermediate filaments: from cell architecture to nanomechanics | journal = Nature Reviews. Molecular Cell Biology | volume = 8 | issue = 7 | pages = 562–73 | date = July 2007 | pmid = 17551517 | doi = 10.1038/nrm2197 | s2cid = 27115011 }}</ref> [[Keratin]] intermediate filaments in [[epithelial]] cells provide protection for different mechanical stresses the skin may endure. They also provide protection for organs against metabolic, oxidative, and chemical stresses. Strengthening of epithelial cells with these intermediate filaments may prevent onset of [[apoptosis]], or cell death, by reducing the probability of stress.<ref>{{cite journal | vauthors = Pan X, Hobbs RP, Coulombe PA | title = The expanding significance of keratin intermediate filaments in normal and diseased epithelia | journal = Current Opinion in Cell Biology | volume = 25 | issue = 1 | pages = 47–56 | date = February 2013 | pmid = 23270662 | pmc = 3578078 | doi = 10.1016/j.ceb.2012.10.018 }}</ref>

Intermediate filaments are most commonly known as the support system or "scaffolding" for the cell and nucleus while also playing a role in some cell functions. In combination with proteins and [[desmosome]]s, the intermediate filaments form cell-cell connections and anchor the cell-matrix junctions that are used in messaging between cells as well as vital functions of the cell. These connections allow the cell to communicate through the desmosome of multiple cells to adjust structures of the tissue based on signals from the cells environment. Mutations in the IF proteins have been shown to cause serious medical issues such as premature aging, desmin mutations compromising organs, [[Alexander disease|Alexander Disease]], and [[muscular dystrophy]].<ref name="Herrmann"/>

Different intermediate filaments are:
* made of [[vimentin]]s. Vimentin intermediate filaments are in general present in mesenchymal cells.
* made of [[keratin]]. Keratin is present in general in epithelial cells.
* [[neurofilament]]s of neural cells.
* made of [[lamin]], giving structural support to the nuclear envelope.
* made of [[desmin]], play an important role in structural and mechanical support of muscle cells.<ref>{{cite journal | vauthors = Paulin D, Li Z | title = Desmin: a major intermediate filament protein essential for the structural integrity and function of muscle | journal = Experimental Cell Research | volume = 301 | issue = 1 | pages = 1–7 | date = November 2004 | pmid = 15501438 | doi = 10.1016/j.yexcr.2004.08.004 }}</ref>