Hyperkinesia
A tic can be defined as a repeated, individually recognizable, intermittent movement or movement fragments that are almost always briefly suppressible and are usually associated with awareness of an urge to perform the movement. These abnormal movements occur with intervening periods of normal movement. These movements are predictable, often triggered by stress, excitement, suggestion, or brief voluntary suppressibility. Many children say that the onset of tics can stem from the strong urge to move. Tics can be either muscular (alter normal motor function) or vocal (alter normal speech) in nature and most commonly involve the face, mouth, eyes, head, neck or shoulder muscles. Tics can also be classified as simple motor tics (a single brief stereotyped movement or movement fragment), complex motor tics (a more complex or sequential movement involving multiple muscle
groups), or phonic tics (including simple, brief phonations or vocalizations).
Kinesin family member 11
KIF11 (also known as kinesin-5 and Eg5) is a homotetramer which cross-links anti-parallel microtubules in the mitotic spindle to maintain spindle bipolarity. The motor domain or motor head is at the N-terminus and performs ATP hydrolysis and binds to microtubules. Kinesin-5 motors assemble into a bipolar homotetrameric structure that is capable of sliding apart bundles of anti-parallel oriented microtubules. This motor is essential for mitosis in most organisms, wherein it participates in the self-assembly of the microtubule-based mitotic spindle, but is not otherwise required for cell viability. The motor may also play a role in the proper development of mammalian neuronal processes, including growth cone navigation and elongation.