| Gene Symbol | FAM20B |
|---|---|
| Entrez Gene | 9917 |
| Alt Symbol | gxk1 |
| Species | Human |
| Gene Type | protein-coding |
| Description | family with sequence similarity 20, member B |
| Other Description | glycosaminoglycan xylosylkinase|xylose kinase |
| Swissprots | Q5W0C3 Q5W0C4 O75063 |
| Accessions | EAW91034 EAW91035 EAW91036 O75063 AB007944 BAA32320 AB480690 BAH79819 AK289989 BAF82678 BC046441 AAH46441 BC051794 AAH51794 CA844342 XM_011510224 XP_011508526 XM_011510225 XP_011508527 XM_011510226 XP_011508528 NM_014864 NP_055679 |
| Function | Responsible for the 2-O-phosphorylation of xylose in the glycosaminoglycan-protein linkage region of proteoglycans thereby regulating the amount of mature GAG chains. Sulfated glycosaminoglycans (GAGs), including heparan sulfate and chondroitin sulfate, are synthesized on the so-called common GAG- protein linkage region (GlcUAbeta1-3Galbeta1-3Galbeta1-4Xylbeta1- O-Ser) of core proteins, which is formed by the stepwise addition of monosaccharide residues by the respective specific glycosyltransferases. Xylose 2-O-phosphorylation may influence the catalytic activity of B3GAT3 (GlcAT-I) which completes the precursor tetrasaccharide of GAG-protein linkage regions on which the repeating disaccharide region is synthesized. {ECO:0000269|PubMed:19473117, ECO:0000269|PubMed:24425863}. |
| Subcellular Location | Golgi apparatus membrane {ECO:0000269|PubMed:19473117}; Single-pass type II membrane protein {ECO:0000269|PubMed:19473117}. |
| Tissue Specificity | Widely expressed. Strongly expressed in pancreas, spleen and fetal liver. {ECO:0000269|PubMed:15676076, ECO:0000269|PubMed:24425863}. |