TY - JOUR
T1 - Dynamic interplay between catalytic and lectin domains of GalNAc-transferases modulates protein O-glycosylation
AU - Lira-Navarrete, Erandi
AU - de Las Rivas, Matilde
AU - Compañón, Ismael
AU - Pallarés, María Carmen
AU - Kong, Yun
AU - Iglesias-Fernández, Javier
AU - Bernardes, Gonçalo J L
AU - Peregrina, Jesús M
AU - Rovira, Carme
AU - Bernadó, Pau
AU - Bruscolini, Pierpaolo
AU - Clausen, Henrik
AU - Lostao, Anabel
AU - Corzana, Francisco
AU - Hurtado-Guerrero, Ramon
PY - 2015/5/5
Y1 - 2015/5/5
N2 - Protein O-glycosylation is controlled by polypeptide GalNAc-transferases (GalNAc-Ts) that uniquely feature both a catalytic and lectin domain. The underlying molecular basis of how the lectin domains of GalNAc-Ts contribute to glycopeptide specificity and catalysis remains unclear. Here we present the first crystal structures of complexes of GalNAc-T2 with glycopeptides that together with enhanced sampling molecular dynamics simulations demonstrate a cooperative mechanism by which the lectin domain enables free acceptor sites binding of glycopeptides into the catalytic domain. Atomic force microscopy and small-angle X-ray scattering experiments further reveal a dynamic conformational landscape of GalNAc-T2 and a prominent role of compact structures that are both required for efficient catalysis. Our model indicates that the activity profile of GalNAc-T2 is dictated by conformational heterogeneity and relies on a flexible linker located between the catalytic and the lectin domains. Our results also shed light on how GalNAc-Ts generate dense decoration of proteins with O-glycans.
AB - Protein O-glycosylation is controlled by polypeptide GalNAc-transferases (GalNAc-Ts) that uniquely feature both a catalytic and lectin domain. The underlying molecular basis of how the lectin domains of GalNAc-Ts contribute to glycopeptide specificity and catalysis remains unclear. Here we present the first crystal structures of complexes of GalNAc-T2 with glycopeptides that together with enhanced sampling molecular dynamics simulations demonstrate a cooperative mechanism by which the lectin domain enables free acceptor sites binding of glycopeptides into the catalytic domain. Atomic force microscopy and small-angle X-ray scattering experiments further reveal a dynamic conformational landscape of GalNAc-T2 and a prominent role of compact structures that are both required for efficient catalysis. Our model indicates that the activity profile of GalNAc-T2 is dictated by conformational heterogeneity and relies on a flexible linker located between the catalytic and the lectin domains. Our results also shed light on how GalNAc-Ts generate dense decoration of proteins with O-glycans.
U2 - 10.1038/ncomms7937
DO - 10.1038/ncomms7937
M3 - Journal article
C2 - 25939779
VL - 6
JO - Nature Communications
JF - Nature Communications
SN - 2041-1723
M1 - 6937
ER -