The Shaker (Sh) gene, when mutated, causes a variety of atypical behaviors in the fruit fly, Drosophila melanogaster. Under ether anesthesia, the fly’s legs will shake, and even unanaesthetized the fly exhibits aberrant movements. The fly has a shorter lifespan, and in larvae the repetitive firing of action potentials as well as prolonged exposure to neurotransmitters at neuromuscular junctions occurs.
The Sh gene plays a part in the operation of potassium ion channels, which are integral membrane proteins and are essential to the correct functioning of the cell. A working Shaker channel is voltage dependent and has four subunits which form a pore through which ions flow, carrying type A potassium current (IA). A mutation in the Sh gene reduces the conductance of charge across the neuron since the channels do not work, causing the severe phenotypical aberrations mentioned above. These types of ion channels are responsible for the repolarization of the cell.
It is located on the X chromosome.
Recently, the Shaker gene has also been identified as a gene helps determine an organism's amount of sleep. The phenotype of the flies that need less sleep is called minisleep (mns).
A large portion of the above is taken from material made available in the Cornell University course, BioNB222, Introduction to Neurobiology: <http://instruct1.cit.cornell.edu/courses/bionb222/secure/FruitFly/index.html>. This is a secure link for students of BioNB 222.