Synuclein

Synucleins are a family of soluble proteins common to vertebrates, primarily expressed in neural tissue and in certain tumors.
Family members.
The synuclein family includes three known proteins: alpha-synuclein, beta-synuclein, and gamma-synuclein. Interest in the synuclein family began when alpha-synuclein was found to be mutated in several families with autosomal dominant Parkinson's disease.
All synucleins have in common a highly conserved alpha-helical lipid-binding motif with similarity to the class-A2 lipid-binding domains of the exchangeable apolipoproteins. Synuclein family members are not found outside vertebrates, although they have some conserved structural similarity with plant 'late-embryo-abundant' proteins.
Function.
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. Mutations in alpha-synuclein are associated with early-onset familial Parkinson's disease and the protein aggregates abnormally in Parkinson's disease, Alzheimer's disease, Lewy body disease, and other neurodegenerative diseases. The gamma-synuclein protein's expression in breast tumors is a marker for tumor progression.
Human proteins containing this domain.
SNCA; SNCB; SNCG;