ISSN:
1442-2042
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Medicine
Notes:
Apg-1 encodes a heat shock protein belonging to the Hsp110 family and is inducible by a 32°C to 39°C heat shock in somatic cells. In mouse testicular germ cells Apg-1 mRNA is constitutively expressed depending on the developmental stage. As human Apg-1 has recently been identified, the expression of Apg-1 in the human testis and sperm was investigated.〈section xml:id="abs1-3"〉〈title type="main"〉Methods:Expression and heat-inducibility of Apg-1 in the human testicular germ cell tumor cell line, NEC8, was analyzed. Using an antimouse Apg-1 antibody, expression of Apg-1 in the human testis and sperm was examined by western blotting after confirmation of the specificity of the antibody. The cells expressing Apg-1 in the testis were further determined by immunohistochemistry.〈section xml:id="abs1-4"〉〈title type="main"〉Results:Slight induction of Apg-1 mRNA was detected in NEC8 cells after 32°C to 39°C temperature shift. In the human testis, the antibody specifically recognized Apg-1, which was absent in the testis without germ cells (Sertoli-cell-only syndrome) or arrested at spermatogonia. Spermatocytes and spermatids, but not testicular somatic cells, were positively stained with the anti-Apg-1 antibody. By western blot analysis, Apg-1 was detected in the preparation enriched for sperm from normal volunteers and infertile patients, but not from azoospermia patients.〈section xml:id="abs1-5"〉〈title type="main"〉Conclusion:Apg-1 is developmentally expressed in human testicular germ cells and sperm, suggesting its role in spermatogenesis and fertilization. Identification of substrates for Apg-1 chaperone activity will help elucidate its function.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1046/j.1442-2042.2001.00304.x
