User:Dhail/Protein filament

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In biology, a protein filament is a "long chain of proteins, such as those found in hair, muscle, or in flagella." [ ] Protein filaments form together to make the cytoskeleton of the cell. They are often bundled together to provide support, strength, and rigidity to the cell. When the filaments are packed up together, they are able to form three different cellular parts. These three cellular parts make up the cytoskeleton, where each structure has its own size and protein composition. The three cellular examples include:


 * Microfilaments
 * Microtubules
 * Intermediate filaments



Microfilaments
Main article: Microfilaments

Compared to the other parts of the cytoskeletons, the microfilaments contain the thinnest filaments, with a diameter of approximately 7nm. Microfilaments are part of the cytoskeleton that are composed of protein called actin. Microfilaments can either occur in the monomeric G-actin or filamentous F-actin. [ ]



Microtubules
Main article: Microtubules

Microtubules are the largest type of filament, with a diameter of 25 nm wide, in the cytoskeleton. [ ] A single microtubule consists of 13 linear microfilaments. Unlike microfilaments, microtubules are composed of a protein called tubulin. The tubulin consists of dimers, named either "αβ-tubulin" or "tubulin dimers", which polymerize to form the microtubules. [ ]



Intermediate filaments
Main article: Intermediate filaments

Intermediate filaments are part of the cytoskeleton structure found in most eukaryotic cells. Intermediate filaments contain an average diameter of 10 nm, which is small than that of microtubules, but larger than that of microfilaments. [ ]