ST8 alpha-N-acetyl-neuraminide alpha-2,8-sialyltransferase 5 (ST8SIA5)

ST8 alpha-N-acetyl-neuraminide alpha-2,8-sialyltransferase 5 (ST8SIA5) is a protein-coding gene that encodes a type II membrane protein localized predominantly to the Golgi apparatus, classified as a member of glycosyltransferase family 29[3][8][9]. ST8SIA5 catalyzes the transfer of sialic acid in an alpha-2,8 linkage, thereby synthesizing complex gangliosides such as GD1c, GT1a, GQ1b, and GT3 from precursor molecules including GD1a, GT1b, GM1b, and GD3[3][1][9]. The protein is implicated in neural development, membrane composition, and cell signaling, and has three isoforms with distinct subcellular localization patterns. Disease associations include rare hereditary spastic paraplegia and possible links to melanoma pathobiology. It is considered a potential therapeutic target due to its role in glycosylation and membrane signaling, although no approved drugs currently act directly on ST8SIA5. Safety risks may include neurotoxicity due to its critical role in ganglioside metabolism[1][3][8][9].

Other names

Alpha-2,8-sialyltransferase 8ESIAT8ESIAT8-EST8SiaVSialyltransferase 8ESialyltransferase St8Sia VST8 alpha-N-acetylneuraminate alpha-2,8-sialyltransferase 5Sialyltransferase 8E (alpha-2,8-polysialytransferase)SIA8E

Inhibition or modulation of sialyltransferase activity: In theory, drugs targeting ST8SIA5 would inhibit its enzymatic activity, thus shifting ganglioside composition and potentially altering cell signaling, adhesion, or immune evasion pathways relevant to cancer or neurological disease[1][3]. - Gene knockout/CRISPR targeting: Functional genomic screens (CRISPR) have targeted ST8SIA5 to study essentiality in cancer cell lines[5].