The interdomain flexible linker of the polypeptide GalNAc transferases dictates their long-range glycosylation preferences. Issue 1 (December 2017)

• Record Type: Journal Article
• Authors: de las Rivas, Matilde; Lira-Navarrete, Erandi; Daniel, Earnest; Compañón, Ismael; Coelho, Helena; Diniz, Ana; Jiménez-Barbero, Jesús; Peregrina, Jesús; Clausen, Henrik; Corzana, Francisco; Marcelo, Filipa; Jiménez-Osés, Gonzalo; Gerken, Thomas; Hurtado-Guerrero, Ramon
• Is Part Of: Nature communications. Volume 8:Issue 1(2017)
• Page Start: 1
• Page End: 11
• Publication Date: 2017-12
• Subjects: Biology -- Periodicals; Physical sciences -- Periodicals; 505
• DOI: 10.1038/s41467-017-02006-0
• Languages: English
• ISSNs: 2041-1723

Abstract

Abstract The polypeptide GalNAc-transferases (GalNAc-Ts), that initiate mucin-typeO -glycosylation, consist of a catalytic and a lectin domain connected by a flexible linker. In addition to recognizing polypeptide sequence, the GalNAc-Ts exhibit unique long-range N- and/or C-terminal prior glycosylation (GalNAc-O -Ser/Thr) preferences modulated by the lectin domain. Here we report studies on GalNAc-T4 that reveal the origins of its unique N-terminal long-range glycopeptide specificity, which is the opposite of GalNAc-T2. The GalNAc-T4 structure bound to a monoglycopeptide shows that the GalNAc-binding site of its lectin domain is rotated relative to the homologous GalNAc-T2 structure, explaining their different long-range preferences. Kinetics and molecular dynamics simulations on several GalNAc-T2 flexible linker constructs show altered remote prior glycosylation preferences, confirming that the flexible linker dictates the rotation of the lectin domain, thus modulating the GalNAc-Ts' long-range preferences. This work for the first time provides the structural basis for the different remote prior glycosylation preferences of the GalNAc-Ts. GalNAc transferases' (GalNAc-Ts) catalytic domains are connected to a lectin domain through a flexible linker. Here the authors present a structural analysis of GalNAc-T4 that implicates the linker region as modulator of the orientations of the lectin domain, which in turn imparts substrate specificity.