ST8SIA2

ST8SIA2, also known as alpha-2,8-sialyltransferase 2, is an enzyme encoded by the ST8SIA2 gene in humans. It belongs to the family of sialyltransferases, which are responsible for the transfer of sialic acid residues to glycoconjugates, such as glycoproteins and glycolipids. Specifically, ST8SIA2 catalyzes the formation of polysialic acid chains by linking sialic acid molecules via alpha-2,8-glycosidic bonds. These polysiaic acid chains are critical for modulating cell-cell interactions, neurodevelopment, and immune responses.

The expression of ST8SIA2 is predominantly observed in the brain and neural tissues, where it plays a key role in neural plasticity, cell migration, and synaptic development. Its activity is vital for proper central nervous system function and has been associated with neurodevelopmental processes. Variations or mutations in the ST8SIA2 gene have been linked to neuropsychiatric disorders, including schizophrenia, bipolar disorder, and autism spectrum disorders, suggesting its significance in mental health.

Structurally, ST8SIA2 is a type II transmembrane protein situated in the Golgi apparatus, where it facilitates the glycosylation of proteins and lipids during cellular processing. This enzyme requires specific donor substrates, such as CMP-Neu5Ac, for its sialyltransferase activity.

Research on ST8SIA2 continues to explore its broader biological functions and potential as a therapeutic target for neurological and psychiatric conditions. Its role in neural development and immune modulation underscores its importance within the complex network of cellular interactions and signaling pathways in humans.