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Interaction mode between catalytic and regulatory subunits in glucosidase II involved in ER glycoprotein quality control.

ABSTRACT: The glycoside hydrolase family 31 (GH31) ?-glucosidases play vital roles in catabolic and regulated degradation, including the ?-subunit of glucosidase II (GII?), which catalyzes trimming of the terminal glucose residues of N-glycan in glycoprotein processing coupled with quality control in the endoplasmic reticulum (ER). Among the known GH31 enzymes, only GII? functions with its binding partner, regulatory ?-subunit (GII?), which harbors a lectin domain for substrate recognition. Although the structural data have been reported for GII? and the GII? lectin domain, the interaction mode between GII? and GII? remains unknown. Here, we determined the structure of a complex formed between GII? and the GII?-binding domain of GII?, thereby providing a structural basis underlying the functional extension of this unique GH31 enzyme.

SUBMITTER: Satoh T

PROVIDER: S-EPMC5079260 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Interaction mode between catalytic and regulatory subunits in glucosidase II involved in ER glycoprotein quality control.

Satoh Tadashi T Toshimori Takayasu T Noda Masanori M Uchiyama Susumu S Kato Koichi K

Protein science : a publication of the Protein Society 20160914 11

The glycoside hydrolase family 31 (GH31) α-glucosidases play vital roles in catabolic and regulated degradation, including the α-subunit of glucosidase II (GIIα), which catalyzes trimming of the terminal glucose residues of N-glycan in glycoprotein processing coupled with quality control in the endoplasmic reticulum (ER). Among the known GH31 enzymes, only GIIα functions with its binding partner, regulatory β-subunit (GIIβ), which harbors a lectin domain for substrate recognition. Although the s ...[more]

PMID: 27576940

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