Search results
Results from the WOW.Com Content Network
In 1903, Nikolai K. Koltsov proposed that the shape of cells was determined by a network of tubules that he termed the cytoskeleton. The concept of a protein mosaic that dynamically coordinated cytoplasmic biochemistry was proposed by Rudolph Peters in 1929 [12] while the term (cytosquelette, in French) was first introduced by French embryologist Paul Wintrebert in 1931.
The cellular cytoskeleton is a dynamic system that functions on many different levels: In addition to giving the cell a particular form and supporting the transport of vesicles and organelles, it can also influence gene expression. The signal transduction mechanisms involved in this communication are little understood.
Intermediate filaments (IFs) are cytoskeletal structural components found in the cells of vertebrates, and many invertebrates. [1] [2] [3] Homologues of the IF protein have been noted in an invertebrate, the cephalochordate Branchiostoma.
Microfilament functions include cytokinesis, amoeboid movement, cell motility, changes in cell shape, endocytosis and exocytosis, cell contractility, and mechanical stability. Microfilaments are flexible and relatively strong, resisting buckling by multi-piconewton compressive forces and filament fracture by nanonewton tensile forces.
In neuronal axons, the actin or spectric cytoskeleton forms an array of periodic rings [10] and in the sperm flagellum it forms a helical structure. [11] In plant cells, the cell cortex is reinforced by cortical microtubules underlying the plasma membrane. The direction of these cortical microtubules determines which way the cell elongates when ...
Microtubules function in many essential cellular processes, including mitosis. Tubulin-binding drugs kill cancerous cells by inhibiting microtubule dynamics, which are required for DNA segregation and therefore cell division. In eukaryotes, there are six members of the tubulin superfamily, although not all are present in all species.
The eukaryotic cytoskeleton is composed of microtubules, intermediate filaments and microfilaments. In the cytoskeleton of a neuron the intermediate filaments are known as neurofilaments. There are a great number of proteins associated with them, each controlling a cell's structure by directing, bundling, and aligning filaments. [2]
Elements of the Caulobacter crescentus cytoskeleton. The prokaryotic cytoskeletal elements are matched with their eukaryotic homologue and hypothesized cellular function. [1] The prokaryotic cytoskeleton is the collective name for all structural filaments in prokaryotes. [2]