1fo2

Structural highlights

Disease

MA1B1_HUMAN Defects in MAN1B1 are the cause of mental retardation autosomal recessive type 15 (MRT15) [MIM:614202. Mental retardation is characterized by significantly below average general intellectual functioning associated with impairments in adaptative behavior and manifested during the developmental period.^[1]

Function

MA1B1_HUMAN 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).^{[2] [3]}

Evolutionary Conservation

Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.

See Also

• Mannosidase 3D structures

References

1. ↑ Rafiq MA, Kuss AW, Puettmann L, Noor A, Ramiah A, Ali G, Hu H, Kerio NA, Xiang Y, Garshasbi M, Khan MA, Ishak GE, Weksberg R, Ullmann R, Tzschach A, Kahrizi K, Mahmood K, Naeem F, Ayub M, Moremen KW, Vincent JB, Ropers HH, Ansar M, Najmabadi H. Mutations in the alpha 1,2-mannosidase gene, MAN1B1, cause autosomal-recessive intellectual disability. Am J Hum Genet. 2011 Jul 15;89(1):176-82. doi: 10.1016/j.ajhg.2011.06.006. PMID:21763484 doi:10.1016/j.ajhg.2011.06.006
2. ↑ Herscovics A, Romero PA, Tremblay LO. The specificity of the yeast and human class I ER alpha 1,2-mannosidases involved in ER quality control is not as strict previously reported. Glycobiology. 2002 Apr;12(4):14G-15G. PMID:12090241
3. ↑ Avezov E, Frenkel Z, Ehrlich M, Herscovics A, Lederkremer GZ. Endoplasmic reticulum (ER) mannosidase I is compartmentalized and required for N-glycan trimming to Man5-6GlcNAc2 in glycoprotein ER-associated degradation. Mol Biol Cell. 2008 Jan;19(1):216-25. Epub 2007 Nov 14. PMID:18003979 doi:10.1091/mbc.E07-05-0505