TY - JOUR
T1 - Reduction of N-linked xylose and fucose by expression of rat β1,4-N-acetylglucosaminyltransferase III in tobacco BY-2 cells depends on Golgi enzyme localization domain and genetic elements used for expression
AU - Karg, Saskia R.
AU - Frey, Alexander D.
AU - Kallio, Pauli T.
PY - 2010/3
Y1 - 2010/3
N2 - Plant-specific N-glycosylation, such as the introduction of core α1,3-fucose and β1,2-xylose residues, is a major obstacle to the utilization of plant cell- or plant-derived recombinant therapeutic proteins. The β1,4-N-acetylglucosaminyltransferase III (GnTIII) introduces a bisecting GlcNAc residue into N-glycans, which exerts a high level of substrate mediated control over subsequent modifications, for example inhibiting mammalian core fucosylation. Based on similar findings in plants, we used Nicotiana tabacum BY-2 cells to study the effects of localization and expression levels of GnTIII in the remodeling of the plant N-glycosylation pathway. The N-glycans produced by the cells expressing GnTIII were partially bisected and practically devoid of the paucimannosidic type which is typical for N-glycans produced by wildtype BY-2 suspension cultured cells. The proportion of human-compatible N-glycans devoid of fucose and xylose could be increased from an average of 4% on secreted protein from wildtype cells to as high as 59% in cells expressing chimeric GnTIII, named GnTIIIA.th. replacing its native localization domain with the cytoplasmic tail, transmembrane, and stem region of Arabidopsis thaliana mannosidase II. The changes in N-glycosylation observed were dependent on the catalytic activity of GnTIII, as the expression of catalytically inactive GnTIII mutants did not show a significant effect on N-glycosylation.
AB - Plant-specific N-glycosylation, such as the introduction of core α1,3-fucose and β1,2-xylose residues, is a major obstacle to the utilization of plant cell- or plant-derived recombinant therapeutic proteins. The β1,4-N-acetylglucosaminyltransferase III (GnTIII) introduces a bisecting GlcNAc residue into N-glycans, which exerts a high level of substrate mediated control over subsequent modifications, for example inhibiting mammalian core fucosylation. Based on similar findings in plants, we used Nicotiana tabacum BY-2 cells to study the effects of localization and expression levels of GnTIII in the remodeling of the plant N-glycosylation pathway. The N-glycans produced by the cells expressing GnTIII were partially bisected and practically devoid of the paucimannosidic type which is typical for N-glycans produced by wildtype BY-2 suspension cultured cells. The proportion of human-compatible N-glycans devoid of fucose and xylose could be increased from an average of 4% on secreted protein from wildtype cells to as high as 59% in cells expressing chimeric GnTIII, named GnTIIIA.th. replacing its native localization domain with the cytoplasmic tail, transmembrane, and stem region of Arabidopsis thaliana mannosidase II. The changes in N-glycosylation observed were dependent on the catalytic activity of GnTIII, as the expression of catalytically inactive GnTIII mutants did not show a significant effect on N-glycosylation.
KW - β1,4-N-acetylglucosaminyltransferase III
KW - Core modifications
KW - N-glycosylation
UR - http://www.scopus.com/inward/record.url?scp=77249131695&partnerID=8YFLogxK
U2 - 10.1016/j.jbiotec.2010.01.005
DO - 10.1016/j.jbiotec.2010.01.005
M3 - Article
C2 - 20083147
AN - SCOPUS:77249131695
SN - 0168-1656
VL - 146
SP - 54
EP - 65
JO - Journal of Biotechnology
JF - Journal of Biotechnology
IS - 1-2
ER -