The role of galectins in mouse development

Galectins are members of a family of carbohydrate-recognizing molecules specific for beta-galactosides, distinguishable from all other animal lectins by their low molecular weight, ranging from 14 kDal to 36 kDal, and their variable subcellular location. Ten members of this gene family have now been identified. Studies of the spatio-temporal distribution of various galectins during embryogenesis have shown that these molecules present very dynamic patterns of expression, suggesting roles in several developmental processes. In an attempt to elucidate the potential functions of these proteins during embryogenesis, we have generated mutants with targeted deletions of galectin-1 and galectin-3 genes. Animals homozygous for either of these mutations are viable and fertile. Despite the coexpression of galectins-1 and -3 on the surface of the embryo at the time of uterine implantation, double homozygote embryos also implant successfully and the combined loss of galectins-1 and 3 does not lead to any overt phenotype. Detailed analysis of these animals is in progress.