Involved in the remodeling of the N-acetyl-glucosamine residues of proteoglycan complexes during reproductive development. Is essential to promote the first divisions of the zygote. Hydrolysis of terminal non-reducing N-acetyl-D-glucosamine residues in N-acetyl-alpha-D-glucosaminides. Expressed during early and late male gametogenesis, and in cells of the embryo sac at the time of fertilization. After fertilization, expressed in the embryo, suspensor, and endosperm until the cotyledon stage embryo. Embryonic lethality when homozygous, due to embryo development arrested at one-cell stage. Belongs to the glycosyl hydrolase 89 family.