Sialyltransferase 4B (SIAT4B)

ST3GAL2 gene contains 7 exons and spans more than 75 kb. The translational start codon is in exon 2. The p1 promoter is located 5-prime of exon 1 and directs transcription of the type-1 ST3GAL2 variant. The deduced protein shares 93.7% similarity with murine St3galII and 49.3% similarity with human ST3GALI (SIAT4A). It contains a putative N-terminal signal-anchor domain, 2 potential N-glycosylation sites, and the conserved histidine and glutamic acids of sialyl motif VS within its C-terminal catalytic domain. Northern blot analysis revealed a single transcript of about 4.2 kb, with high levels in heart, liver, and skeletal muscle, intermediate levels in thymus, lymph node, bone marrow, appendix, and spleen, and low levels in peripheral blood lymphocytes. No transcript was detected in brain or kidney.