The synculein family consists of 3 highly conserved proteins of between 120 and 140 amino acids that share substantial sequence homology. Each has a series of loosely repeated motifs throughout the first 93 amino acids and an acid region toward the C terminal. The proteins are heat stable and relatively soluble. Three synucleins have been identified and termed alpha, beta and gamma synuclein and are located in the neuronal cytosol and enriched in presynaptic terminals,gamma synuclein is also expressed in many other non-neuronal tissues. Although the precise function of the synucleins are unknown a role in membrane plasticity has been suggested. The synucleins have been implicated in a number of diseases. It has been reported that in breast cancer increased expression of gamma synuclein correlates with disease progression.