TY - JOUR
T1 - Multiple domains of GlcNAc-1-phosphotransferase mediate recognition of lysosomal enzymes
AU - Van Meel, Eline
AU - Lee, Wang Sik
AU - Liu, Lin
AU - Qian, Yi
AU - Doray, Balraj
AU - Kornfeld, Stuart
N1 - Publisher Copyright:
© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.
PY - 2016/4/8
Y1 - 2016/4/8
N2 - The Golgi enzyme UDP-GlcNAc:lysosomal enzyme N-acetylglucosamine- 1-phosphotransferase (GlcNAc-1-phosphotransferase), an α2β2γ2 hexamer, mediates the initial step in the addition of the mannose 6-phosphate targeting signal on newly synthesized lysosomal enzymes. This tag serves to direct the lysosomal enzymes to lysosomes. A key property of GlcNAc-1-phosphotransferase is its unique ability to distinguish the 60 or so lysosomal enzymes from the numerous nonlysosomal glycoproteins with identical Asn-linked glycans. In this study, we demonstrate that the two Notch repeat modules and the DNA methyltransferase-associated protein interaction domain of the α subunit are key components of this recognition process. Importantly, different combinations of these domains are involved in binding to individual lysosomal enzymes. This study also identifies the γ-binding site on the α subunit and demonstrates that in the majority of instances the mannose 6-phosphate receptor homology domain of the γ subunit is required for optimal phosphorylation. These findings serve to explain how GlcNAc-1-phosphotransferase recognizes a large number of proteins that lack a common structural motif.
AB - The Golgi enzyme UDP-GlcNAc:lysosomal enzyme N-acetylglucosamine- 1-phosphotransferase (GlcNAc-1-phosphotransferase), an α2β2γ2 hexamer, mediates the initial step in the addition of the mannose 6-phosphate targeting signal on newly synthesized lysosomal enzymes. This tag serves to direct the lysosomal enzymes to lysosomes. A key property of GlcNAc-1-phosphotransferase is its unique ability to distinguish the 60 or so lysosomal enzymes from the numerous nonlysosomal glycoproteins with identical Asn-linked glycans. In this study, we demonstrate that the two Notch repeat modules and the DNA methyltransferase-associated protein interaction domain of the α subunit are key components of this recognition process. Importantly, different combinations of these domains are involved in binding to individual lysosomal enzymes. This study also identifies the γ-binding site on the α subunit and demonstrates that in the majority of instances the mannose 6-phosphate receptor homology domain of the γ subunit is required for optimal phosphorylation. These findings serve to explain how GlcNAc-1-phosphotransferase recognizes a large number of proteins that lack a common structural motif.
UR - http://www.scopus.com/inward/record.url?scp=84964659773&partnerID=8YFLogxK
U2 - 10.1074/jbc.M116.714568
DO - 10.1074/jbc.M116.714568
M3 - Article
C2 - 26833567
AN - SCOPUS:84964659773
SN - 0021-9258
VL - 291
SP - 8295
EP - 8307
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
IS - 15
ER -