Dataset Information

Carbohydrate deficient glycoprotein syndrome type IV: deficiency of dolichyl-P-Man:Man(5)GlcNAc(2)-PP-dolichyl mannosyltransferase.

ABSTRACT: Type IV of the carbohydrate deficient glycoprotein syndromes (CDGS) is characterized by microcephaly, severe epilepsy, minimal psychomotor development and partial deficiency of sialic acids in serum glycoproteins. Here we show that the molecular defect in the index patient is a missense mutation in the gene encoding the mannosyltransferase that transfers mannose from dolichyl-phosphate mannose on to the lipid-linked oligosaccharide (LLO) intermediate Man(5)GlcNAc(2)-PP-dolichol. The defect results in the accumulation of the LLO intermediate and, due to its leaky nature, a residual formation of full-length LLOs. N-glycosylation is abnormal because of the transfer of truncated oligosaccharides in addition to that of full-length oligosaccharides and because of the incomplete utilization of N-glycosylation sites. The mannosyltransferase is the structural and functional orthologue of the Saccharomyces cerevisiae ALG3 gene.

SUBMITTER: Korner C

PROVIDER: S-EPMC1171744 | biostudies-other | 1999 Dec

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Carbohydrate deficient glycoprotein syndrome type IV: deficiency of dolichyl-P-Man:Man(5)GlcNAc(2)-PP-dolichyl mannosyltransferase.

Körner C C Knauer R R Stephani U U Marquardt T T Lehle L L von Figura K K

The EMBO journal 19991201 23

Type IV of the carbohydrate deficient glycoprotein syndromes (CDGS) is characterized by microcephaly, severe epilepsy, minimal psychomotor development and partial deficiency of sialic acids in serum glycoproteins. Here we show that the molecular defect in the index patient is a missense mutation in the gene encoding the mannosyltransferase that transfers mannose from dolichyl-phosphate mannose on to the lipid-linked oligosaccharide (LLO) intermediate Man(5)GlcNAc(2)-PP-dolichol. The defect resul ...[more]

PMID: 10581255

Similar Datasets

Project description:BACKGROUND: Protein-based therapeutics represent the fastest growing class of compounds in the pharmaceutical industry. This has created an increasing demand for powerful expression systems. Yeast systems are widely used, convenient and cost-effective. Yarrowia lipolytica is a suitable host that is generally regarded as safe (GRAS). Yeasts, however, modify their glycoproteins with heterogeneous glycans containing mainly mannoses, which complicates downstream processing and often interferes with protein function in man. Our aim was to glyco-engineer Y. lipolytica to abolish the heterogeneous, yeast-specific glycosylation and to obtain homogeneous human high-mannose type glycosylation. RESULTS: We engineered Y. lipolytica to produce homogeneous human-type terminal-mannose glycosylated proteins, i.e. glycosylated with Man?GlcNAc? or Man?GlcNAc?. First, we inactivated the yeast-specific Golgi ?-1,6-mannosyltransferases YlOch1p and YlMnn9p; the former inactivation yielded a strain producing homogeneous Man?GlcNAc? glycoproteins. We tested this strain by expressing glucocerebrosidase and found that the hypermannosylation-related heterogeneity was eliminated. Furthermore, detailed analysis of N-glycans showed that YlOch1p and YlMnn9p, despite some initial uncertainty about their function, are most likely the ?-1,6-mannosyltransferases responsible for the addition of the first and second mannose residue, respectively, to the glycan backbone. Second, introduction of an ER-retained ?-1,2-mannosidase yielded a strain producing proteins homogeneously glycosylated with Man?GlcNAc?. The use of the endogenous LIP2pre signal sequence and codon optimization greatly improved the efficiency of this enzyme. CONCLUSIONS: We generated a Y. lipolytica expression platform for the production of heterologous glycoproteins that are homogenously glycosylated with either Man?GlcNAc? or Man?GlcNAc? N-glycans. This platform expands the utility of Y. lipolytica as a heterologous expression host and makes it possible to produce glycoproteins with homogeneously glycosylated N-glycans of the human high-mannose-type, which greatly broadens the application scope of these glycoproteins.

Dataset Information

Carbohydrate deficient glycoprotein syndrome type IV: deficiency of dolichyl-P-Man:Man(5)GlcNAc(2)-PP-dolichyl mannosyltransferase.

Publications

Carbohydrate deficient glycoprotein syndrome type IV: deficiency of dolichyl-P-Man:Man(5)GlcNAc(2)-PP-dolichyl mannosyltransferase.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets