Wakayama T, Koami H, Ariga H, Kobayashi D, Sai Y, Tsuji A et al.. Expression and functional characterization of the adhesion molecule spermatogenic immunoglobulin superfamily in the mouse testis. Biol Reprod 68: 1755-1763

Department of Histology and Embryology, Graduate School of Medical Science, Kanazawa University, Japan.
Biology of Reproduction (Impact Factor: 3.32). 06/2003; 68(5):1755-63. DOI: 10.1095/biolreprod.102.012344
Source: PubMed


Spermatogenic immunoglobulin superfamily (SgIGSF) is a mouse protein belonging to the immunoglobulin superfamily expressed in the spermatogenic cells of seminiferous tubules. We produced a specific polyclonal antibody against SgIGSF. Western blot analysis of the testes from postnatal developing mice using this antibody demonstrated multiple immunopositive bands of 80-130 kDa, which increased in number and size with the postnatal age. Enzymatic N-glycolysis caused reduction in the size of these bands to 70 kDa, indicating that SgIGSF is a glycoprotein and its glycosylation pattern and extent are developmentally regulated. Immunohistochemical analysis of the adult testis demonstrated that SgIGSF was present in the spermatogenic cells in the earlier steps of spermatogenesis and increased in amount from intermediate spermatogonia through zygotene spermatocytes but was diminished in the steps from early pachytene spermatocytes through round spermatids. After meiosis, SgIGSF reappeared in step 7 spermatids and was present in the elongating spermatids until spermiation. The immunoreactivity was localized primarily on the cell membrane. Consistent with the findings in adult testes, the analysis of the developing testes revealed that SgIGSF was expressed separately in the spermatogenic cells in earlier and later phases. Sertoli cells had no expression of SgIGSF, whereas both SgIGSF immunoprecipitated from the testis lysate and produced in COS-7 cells was shown to bind to the surface of Sertoli cells in primary culture. These results suggested that SgIGSF on the surface of spermatogenic cells binds to some membrane molecules on Sertoli cells in a heterophilic manner and thereby may play diverse roles in the spermatogenesis.

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    • "In the testis, Cadm1 is expressed exclusively in spermatogenic cells but not in Sertoli cells. In spermatogenic cells, Cadm1 is expressed in intermediate spermatogonia through to early pachytene spermatocytes as well as in step 7 and later spermatids, whereas it is not expressed in middle pachytene through to step 6 spermatids [23, 24, 26]. Cadm1 not only forms homophilic binding with the same molecule present on spermatogenic cells, but also heterophilic binding with another cell adhesion molecule poliovirus receptor (Pvr), that is present on Sertoli cells [23, 26]. "
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    • "P8340) were purchased from Sigma (St. Louis, MO). Anti-CADM1-cyto antibody was generated according to the method described by Wakayama et al. [12]. This antibody recognizes the C-terminal 20 amino acids of CADM1. "
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