RT Journal Article
SR Electronic
T1 Structural basis of substrate recognition and catalysis by fucosyltransferase 8
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.02.14.949818
DO 10.1101/2020.02.14.949818
A1 Michael A. Järvå
A1 Marija Dramicanin
A1 James P. Lingford
A1 Runyu Mao
A1 Alan John
A1 Kate Jarman
A1 Rhys W. Grinter
A1 Ethan D. Goddard-Borger
YR 2020
UL http://biorxiv.org/content/early/2020/02/15/2020.02.14.949818.abstract
AB Fucosylation of the inner-most N-acetyl-glucosamine (GlcNAc) of N-glycans by fucosyltransferase 8 (FUT8) is an important step in the maturation of complex and hybrid N-glycans. This simple modification can have a dramatic impact on the activity and half-life of glycoproteins. These effects are relevant to understanding the invasiveness of some cancers, the development of monoclonal antibody therapeutics, and to a congenital disorder of glycosylation. The acceptor substrate preferences of FUT8 are well characterised and provide a framework for understanding N-glycan maturation in the Golgi, however the structural basis for these substrate preferences and the mechanism through which catalysis is achieved remains unknown. Here, we describe several structures of mouse and human FUT8 in the apo state and in complex with guanosine diphosphate (GDP), a mimic of the donor substrate, and a glycopeptide acceptor substrate. These structures provide insights into: a unique conformational change associated with donor substrate binding; common strategies employed by fucosyltransferases to coordinate GDP; features that define acceptor substrate preferences; and a likely mechanism for enzyme catalysis. Together with molecular dynamics simulations, the structures also reveal how FUT8 dimerisation plays an important role in defining the acceptor substrate binding site. Collectively, this information significantly builds on our understanding of the core-fucosylation process.