Human Gene MAN2B1 (uc002mub.2) Description and Page Index
Description: Homo sapiens mannosidase, alpha, class 2B, member 1 (MAN2B1), transcript variant 1, mRNA. RefSeq Summary (NM_000528): This gene encodes an enzyme that hydrolyzes terminal, non-reducing alpha-D-mannose residues in alpha-D-mannosides. Its activity is necessary for the catabolism of N-linked carbohydrates released during glycoprotein turnover and it is member of family 38 of glycosyl hydrolases. The full length protein is processed in two steps. First, a 49 aa leader sequence is cleaved off and the remainder of the protein is processed into 3 peptides of 70 kDa, 42 kDa (D) and 13/15 kDa (E). Next, the 70 kDa peptide is further processed into three peptides (A, B and C). The A, B and C peptides are disulfide-linked. Defects in this gene have been associated with lysosomal alpha-mannosidosis. Alternatively spliced transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Mar 2010]. Transcript (Including UTRs) Position: hg19 chr19:12,757,322-12,777,591 Size: 20,270 Total Exon Count: 24 Strand: - Coding Region Position: hg19 chr19:12,757,434-12,777,515 Size: 20,082 Coding Exon Count: 24
ID:MA2B1_HUMAN DESCRIPTION: RecName: Full=Lysosomal alpha-mannosidase; Short=Laman; EC=126.96.36.199; AltName: Full=Lysosomal acid alpha-mannosidase; AltName: Full=Mannosidase alpha class 2B member 1; AltName: Full=Mannosidase alpha-B; Contains: RecName: Full=Lysosomal alpha-mannosidase A peptide; Contains: RecName: Full=Lysosomal alpha-mannosidase B peptide; Contains: RecName: Full=Lysosomal alpha-mannosidase C peptide; Contains: RecName: Full=Lysosomal alpha-mannosidase D peptide; Contains: RecName: Full=Lysosomal alpha-mannosidase E peptide; Flags: Precursor; FUNCTION: Necessary for the catabolism of N-linked carbohydrates released during glycoprotein turnover. Cleaves all known types of alpha-mannosidic linkages. CATALYTIC ACTIVITY: Hydrolysis of terminal, non-reducing alpha-D- mannose residues in alpha-D-mannosides. COFACTOR: Binds 1 zinc ion per subunit (By similarity). SUBCELLULAR LOCATION: Lysosome. PTM: First processed into 3 peptides of 70 kDa, 42 kDa (D) and 13/15 kDa (E). The 70 kDa peptide is further processed into three peptides (A, B and C). The A, B and C peptides are disulfide- linked. PTM: Heavily glycosylated. DISEASE: Defects in MAN2B1 are the cause of lysosomal alpha- mannosidosis (AM) [MIM:248500]. AM is a lysosomal storage disease characterized by accumulation of unbranched oligosaccharide chains. This accumulation is expressed histologically as cytoplasmic vacuolation predominantly in the CNS and parenchymatous organs. Depending on the clinical findings at the age of onset, a severe infantile (type I) and a mild juvenile (type II) form of alpha-mannosidosis are recognized. There is considerable variation in the clinical expression with mental retardation, recurrent infections, impaired hearing and Hurler- like skeletal changes being the most consistent abnormalities. SIMILARITY: Belongs to the glycosyl hydrolase 38 family. SEQUENCE CAUTION: Sequence=AAB03816.1; Type=Erroneous initiation; Sequence=AAC50812.1; Type=Erroneous initiation; WEB RESOURCE: Name=GeneReviews; URL="http://www.ncbi.nlm.nih.gov/sites/GeneTests/lab/gene/MAN2B1"; WEB RESOURCE: Name=Mendelian genes mannosidase, alpha, class 2B, member 1 (MAN2B1); Note=Leiden Open Variation Database (LOVD); URL="http://www.lovd.nl/MAN2B1";
Genetic Association Studies of Complex Diseases and Disorders
Genetic Association Database (archive): MAN2B1 CDC HuGE Published Literature: MAN2B1
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on O00754
The pictures above may be empty if there is no ModBase structure for the protein. The ModBase structure frequently covers just a fragment of the protein. You may be asked to log onto ModBase the first time you click on the pictures. It is simplest after logging in to just click on the picture again to get to the specific info on that model.
Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.