Expression of β-synuclein in normal human astrocytes

Although alpha- and beta -synucleins are expressed predominantly in presynaptic nerve terminals, recent studies have demonstrated that alpha -synuclein is also expressed in cultured astrocytes and oligodendrocytes. We determined whether alpha -synuclein might be expressed in astrocytes. alpha -Synuclein mRNA and protein were detected in normal human astrocytes in culture, and immunofluorescent staining showed that beta -synuclein protein was expressed within the cytoplasm and nucleus. Furthermore, beta -synuclein immunoreactivity was present in astrocytes, but not in oligodendrocytes, in normal human brain tissues. Ultrastructurally, beta -synuclein immunoreactivity was found in the cytoplasm of astrocytes, in association with the plasma membrane, ribosomes, rough endoplasmic reticulum and the nuclear outer membrane. The novel expression of beta -synuclein in astrocytes may provide an important insight about the role of this protein. NeuroReport 12:2845-2848 (C) 2001 Lippincott Williams & Wilkins.