Aliases for MAN1B1 Gene
- Mannosidase, Alpha, Class 1B, Member 1 2 3
- Endoplasmic Reticulum Mannosyl-Oligosaccharide 1,2-Alpha-Mannosidase 1 2 3
- Man9GlcNAc2-Specific Processing Alpha-Mannosidase 2 3
- ER Alpha 1,2-Mannosidase 2 3
- ERMAN1 3 4
- MRT15 3 6
- Endoplasmic Reticulum Mannosyl-Oligosaccharide 1,2-Alpha-Mannosidase 3
- Man9GlcNAc2-Specific-Processing Alpha-Mannosidase 4
External Ids for MAN1B1 Gene
Previous GeneCards Identifiers for MAN1B1 Gene
This gene encodes an enzyme belonging to the glycosyl hydrolase 47 family. This enzyme functions in N-glycan biosynthesis, and is a class I alpha-1,2-mannosidase that specifically converts Man9GlcNAc to Man8GlcNAc isomer B. It is required for N-glycan trimming to Man5-6GlcNAc2 in the endoplasmic-reticulum-associated degradation pathway. Mutations in this gene cause autosomal-recessive intellectual disability. Alternative splicing results in multiple transcript variants. A related pseudogene has been identified on chromosome 11. [provided by RefSeq, Dec 2011]
GeneCards Summary for MAN1B1 Gene
MAN1B1 (Mannosidase, Alpha, Class 1B, Member 1) is a Protein Coding gene. Diseases associated with MAN1B1 include mental retardation, autosomal recessive 15 and man1b1-cdg. Among its related pathways are Biosynthesis of the N-glycan precursor (dolichol lipid-linked oligosaccharide, LLO) and transfer to a nascent protein and Biosynthesis of the N-glycan precursor (dolichol lipid-linked oligosaccharide, LLO) and transfer to a nascent protein. GO annotations related to this gene include calcium ion binding and mannosyl-oligosaccharide 1,2-alpha-mannosidase activity. An important paralog of this gene is MAN1C1.
UniProtKB/Swiss-Prot for MAN1B1 Gene
Involved in glycoprotein quality control targeting of misfolded glycoproteins for degradation. It primarily trims a single alpha-1,2-linked mannose residue from Man(9)GlcNAc(2) to produce Man(8)GlcNAc(2), but at high enzyme concentrations, as found in the ER quality control compartment (ERQC), it further trims the carbohydrates to Man(5-6)GlcNAc(2).
Mannosidases are divided into two subtypes; I and II, (EC numbers 18.104.22.168 and 22.214.171.124 respectively) which display a wide expression pattern. Mannosidase I hydrolyzes (1,2)-linked alpha-D-mannose residues in the oligo-mannose oligosaccharide Man9(GlcNAc)2 and mannosidase II hydrolyzes (1,3)- and (1,6)-linked alpha-D-mannose residues in Man5(GlcNAc)3. Both subtypes require a divalent cation cofactor. Mutations in mannosidases can cause mannosidosis (mannosidase I deficiency).