What are the steps in ventral stress fiber formation? Recent data suggests that ventral stress fibers are created by reorganizing pre-existing dorsal stress fibers and transverse arcs [1].Other contrasting models for the formation of ventral stress fibers not covered in this resource include annealing [...]

How is stress fiber assembly regulated? Tension-dependent actin polymerization and assembly of stress fibers is influenced by many factors (reviewed in [1][2]), including differences in substrate composition [3], rigidity [4][5][6] (reviewed in [7]), cell membrane phospholipids [8], external force (reviewed in [9]), as well [...]

What is axon guidance and the growth cone? Axon guidance is an important step in neural development. It allows growing axons to reach specific destinations and ultimately form the complex neuronal networks throughout the body. Although many aspects of this mechanism remains unclear, it [...]

What are Motor Proteins? Motor proteins, such as myosins and kinesins, move along cytoskeletal filaments via a force-dependent mechanism that is driven by the hydrolysis of ATP molecules (reviewed in [1]). Nucleotide hydrolysis and controlled inorganic phosphate release by motor proteins causes restructuring of [...]

What steps are involved in the myosin powerstroke? Each myosin motor protein possesses ATPase activity and functions in a cyclical manner that couples ATP binding and hydrolysis to a conformational change in the protein. This process is known as the ‘powerstroke cycle’ (reviewed in [...]

What is Myosin Light Chain Kinase? Myosin light chain kinase (MLCK) is a calcium/calmodulin-dependent serine/threonine kinase, belonging to the immunoglobulin superfamily. It phosphorylates the regulatory myosin light chains of myosin II, in order to facilitate myosin binding to actin and therefore aid contractility. Its [...]

What are cytoskeletal cages? Cytoskeletal components can assemble into cage-like structures within the cell. These cages serve to segregate intracellular regions or organelles, and can protect their contents from mechanical stress. At the level of the whole cell, the cell cortex is a meshwork [...]

What are septins? Septins are highly conserved small GTP binding proteins of 30-65 kDa, recognized as a unique component of the cytoskeleton {reviewed in [1]}. Septin monomers assemble into hetero oligomeric complexes and polymerize into filaments which can associate with the membrane and other [...]

What is the role of septins in infection? Host (human) septins play a role in bacterial pathogenesis [1] and in host defense mechanisms, mainly, autophagy [2]. Although actin is the most commonly exploited cytoskeletal protein by many bacterial pathogens, septins, which are unique cytoskeletal [...]

How do bacteria modulate the host cytoskeleton? Some bacterial pathogens gain entry and subvert immune detection by surviving intracellularly. Others remain extracellular, but manipulate host pathways from outside. A common strategy employed by both these pathogens is to modulate or subvert the host cellular [...]

What are actin pedestals? Actin pedestals are raised actin structures formed by the dynamic polymerization of host actin, induced by effector proteins secreted by extracellular pathogens like Enteropathogenic Escherichia coli (EPEC) and Enterohaemorrhagic Escherichia coli (EHEC). Infection by EPEC and EHEC induce attaching and [...]

What are actin comet tails? Actin comet tails are actin structures formed by the dynamic polymerization of actin beneath some species of intracellular bacteria belonging to the genus Listeria, Shigella, Ricketssia, Mycobacterium and Burkholderia. Once bacteria gain entry into the cytosol, the endocytic vesicle [...]