Sialate O-acetylesterase (SIAE, ) is a lysosomal enzyme that removes the O-acetyl ester groups from position 9 of the parent sialic acid, N-acetylneuraminic acid. In humans, it is highly expressed in the testis, prostate, and colon []. It negatively regulates B lymphocyte antigen receptor signalling and is required for the maintenance of immunological tolerance. Mutations in the gene result in autoimmune disease 6 []. This entry also includes some uncharacterised bacterial proteins.
This entry represents a domain found in eukaryotic sialic acid acetylesterases (SIAEs). The catalytic triad of this esterase enzyme comprises residues Ser127, His403 and Asp391 in mouse SIAE [, ]. Proteins containing this domain also include some uncharacterised bacterial proteins.
