FIG 1.

Core fucosylation level of milk N-glycan is associated with maternal Fut8 gene status. (A) Sketch map of how Fut8 catalyzes the transfer of an L-fucose residue from GDP-fucose to the innermost N-acetylglucosamine (GlcNAc) on the asparagine (Asn) residue of N-glycans via α1,6 linkage. (B) Mass spectrometry of N-glycan structures of breast milk protein derived from Chinese mothers. Red triangles, fucose; blue squares, GlcNAc; green circles, mannose; yellow circles, galactose; purple diamonds, NeuAc. (C) The rs10483776 SNP (A→G) allele of the maternal Fut8 gene detected by DNA sequencing. (D) Fut8 enzyme activities in the cells of breast milk detected by high-performance liquid chromatography (HPLC). Activity was expressed as picomoles of GDP-fucose transferred to the acceptor per hour per milligram of protein. S is the peptide substrate, and P is the product of fucosylation. (E) Densitometric analysis of the bands of AOL in each breast milk sample between the G and A groups at days 6 and 42 postpartum. Data are shown as mean ± SEM (*, P < 0.05; **, P < 0.01; ***, P < 0.001).