Synucleins are a family of soluble proteins common to vertebrates, primarily expressed in neural tissue and in certain tumors.
[2] The synuclein family includes three known proteins: alpha-synuclein, beta-synuclein, and gamma-synuclein.
Synuclein family members are not found outside vertebrates, although they have some conserved structural similarity with plant 'late-embryo-abundant' proteins.
[1] Normal cellular functions have not been determined for any of the synuclein proteins.
Some data suggest a role in the regulation of membrane stability and/or turnover.