Tags

Type your tag names separated by a space and hit enter

Species-specific differences in the processing of acid α-glucosidase are due to the amino acid identity at position 201.
Gene. 2012 Jan 01; 491(1):25-30.GENE

Abstract

Acid α-glucosidase (GAA) is a lysosomal enzyme that hydrolyzes glycogen to glucose. Deficiency of GAA causes Pompe disease. Mammalian GAA is synthesized as a precursor of ~110,000 Da that is N-glycosylated and targeted to the lysosome via the M6P receptors. In the lysosome, human GAA is sequentially processed by proteases to polypeptides of 76-, 19.4-, and 3.9-kDa that remain associated. Further cleavage between R(200) and A(204) inefficiently converts the 76-kDa polypeptide to the mature 70-kDa form with an additional 10.4-kDa polypeptide. GAA maturation increases its affinity for glycogen by 7-10 fold. In contrast to human GAA, processing of bovine and hamster GAA to the 70-kDa form is more rapid. A comparison of sequences surrounding the cleavage site revealed human GAA contains histidine at 201 while other species contain hydrophobic amino acids at position 201 in the otherwise conserved sequence. Recombinant human GAA (rhGAA) containing the H201L substitution was expressed in 293 T cells by transfection. Pulse chase experiments in 293 T cells expressing rhGAA with or without the H201L substitution revealed rapid processing of rhGAA(H201L) but not rhGAA(WT) to the 70-kDa form. Similarly, when GAA precursor was endocytosed by human Pompe fibroblasts rhGAA(H201L) but not rhGAA(WT) was rapidly converted to the 70-kDa mature GAA. These studies indicate that the amino acid at position 201 influences the rate of conversion of 76-kDa GAA to 70-kDa GAA. The GAA sequence rather than the lysosomal protease environment explains the predominance of the 76-kDa form in human tissues.

Authors+Show Affiliations

Genzyme Corporation, Framingham, Massachusetts 01701, USA. rod.moreland@genzyme.comNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

21963446

Citation

Moreland, Rodney J., et al. "Species-specific Differences in the Processing of Acid Α-glucosidase Are Due to the Amino Acid Identity at Position 201." Gene, vol. 491, no. 1, 2012, pp. 25-30.
Moreland RJ, Higgins S, Zhou A, et al. Species-specific differences in the processing of acid α-glucosidase are due to the amino acid identity at position 201. Gene. 2012;491(1):25-30.
Moreland, R. J., Higgins, S., Zhou, A., VanStraten, P., Cauthron, R. D., Brem, M., McLarty, B. J., Kudo, M., & Canfield, W. M. (2012). Species-specific differences in the processing of acid α-glucosidase are due to the amino acid identity at position 201. Gene, 491(1), 25-30. https://doi.org/10.1016/j.gene.2011.09.011
Moreland RJ, et al. Species-specific Differences in the Processing of Acid Α-glucosidase Are Due to the Amino Acid Identity at Position 201. Gene. 2012 Jan 1;491(1):25-30. PubMed PMID: 21963446.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Species-specific differences in the processing of acid α-glucosidase are due to the amino acid identity at position 201. AU - Moreland,Rodney J, AU - Higgins,Sheri, AU - Zhou,AnQiang, AU - VanStraten,Peter, AU - Cauthron,Robert D, AU - Brem,Michael, AU - McLarty,Beverly J, AU - Kudo,Mariko, AU - Canfield,William M, Y1 - 2011/09/22/ PY - 2011/06/18/received PY - 2011/08/08/revised PY - 2011/09/13/accepted PY - 2011/10/4/entrez PY - 2011/10/4/pubmed PY - 2012/1/11/medline SP - 25 EP - 30 JF - Gene JO - Gene VL - 491 IS - 1 N2 - Acid α-glucosidase (GAA) is a lysosomal enzyme that hydrolyzes glycogen to glucose. Deficiency of GAA causes Pompe disease. Mammalian GAA is synthesized as a precursor of ~110,000 Da that is N-glycosylated and targeted to the lysosome via the M6P receptors. In the lysosome, human GAA is sequentially processed by proteases to polypeptides of 76-, 19.4-, and 3.9-kDa that remain associated. Further cleavage between R(200) and A(204) inefficiently converts the 76-kDa polypeptide to the mature 70-kDa form with an additional 10.4-kDa polypeptide. GAA maturation increases its affinity for glycogen by 7-10 fold. In contrast to human GAA, processing of bovine and hamster GAA to the 70-kDa form is more rapid. A comparison of sequences surrounding the cleavage site revealed human GAA contains histidine at 201 while other species contain hydrophobic amino acids at position 201 in the otherwise conserved sequence. Recombinant human GAA (rhGAA) containing the H201L substitution was expressed in 293 T cells by transfection. Pulse chase experiments in 293 T cells expressing rhGAA with or without the H201L substitution revealed rapid processing of rhGAA(H201L) but not rhGAA(WT) to the 70-kDa form. Similarly, when GAA precursor was endocytosed by human Pompe fibroblasts rhGAA(H201L) but not rhGAA(WT) was rapidly converted to the 70-kDa mature GAA. These studies indicate that the amino acid at position 201 influences the rate of conversion of 76-kDa GAA to 70-kDa GAA. The GAA sequence rather than the lysosomal protease environment explains the predominance of the 76-kDa form in human tissues. SN - 1879-0038 UR - https://www.unboundmedicine.com/medline/citation/21963446/Species_specific_differences_in_the_processing_of_acid_α_glucosidase_are_due_to_the_amino_acid_identity_at_position_201_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0378-1119(11)00511-7 DB - PRIME DP - Unbound Medicine ER -