A subtractive gene expression screen suggests a role for vanin-1 in testisdevelopment in mice

The molecular pathways leading from indifferent mammalian gonad to either t estis or ovary are not well understood. A number of genes, including the Y- linked sex determining gene SRY, have been shown to play roles in sex deter mination or differentiation, but there are clearly many missing elements to be found. We used suppression-subtractive hybridization to construct norma lized cDNA libraries enriched for male-specific or female-specific transcri pts in mouse fetal gonads. We describe the strategy used to efficiently scr een these libraries for candidate sex-determination and gonado-genesis gene s. One gene arising from these screens is vanin-1, which encodes a protein implicated in the induction of cell migration into the thymus. We find that vanin-1 is expressed male-specifically in Sertoli cells of the developing testis and may be involved in inducing cell migration from the adjacent mes onephros, a process known to be critical for testis development. This scree ning approach is likely to be applicable to the isolation and study of gene s involved in a variety of developmental systems. (C) 2000 Wiley-Liss, Inc.