Deficiency of reproductive tract α(1,2)fucosylated glycans and normal fertility in mice with targeted deletions of the FUT1 or FUT2 α(1,2)fucosyltransferase locus

The fucose alpha (1 -->2) galactose beta structure is expressed by uterine epithelial cells in the mouse and has been implicated in blastocyst adhesion events thought to be required for murine implantation. Fuc alpha (1 -->2)Gal beta moieties and cognate fucosyltransferases are also expressed by epithelial cells of the male reproductive tract and have been implicated in sperm maturation events that may contribute to fertilization. To determine directly if Fuca(1 -->2)Gal beta moieties are required for fertility, we have generated strains of mice that are deficient in genes encoding FUT1 and FUT2, a pair of GDP-L-fucose:beta (1 -->4)-D-galactosyl-R 2-alpha -L-fucosyl-transferase enzymes (EC 2.4.1.69) responsible for Fuc alpha (1 -->2)Galp synthesis and expression. FUT1 null mice and FUT2 null mice develop normally and exhibit no gross phenotypic abnormalities. The Fuc alpha (1 -->2)Gal beta epitope is absent from the uterine epithelia of FUT2 null mice and from the epithelia of the epididymis of FUT1 null mice. Fully normal fertility is observed in FUT1. null intercrosses and in FUT2 null intercrosses. These observations indicate that Fuc alpha (1 -->2)Galp moieties are not essential to blastocyst-uterine epithelial cell interactions required for implantation and are not required for sperm maturation events that permit fertilization and that neither the FUT loci nor their cognate fucosylated glycans are essential to normal development.