Amida predominantly expressed and developmentally regulated in rat testis

Amida was first isolated from a rat hippocampal cDNA library as an Are-asso ciated protein Previous studies showed that Amida is a nuclear protein and overexpression of Amida induces cell apoptosis. In this study, we found tha t Amida mRNA was expressed predominantly in rat testis by Northern blot ana lysis. During the development of testis, Amida mRNA was barely detectable u ntil postnatal days 24 to 29 during which it increased to levels found in a dults. However, Amida protein was not detected until postnatal day 32. Amid a mRNA was found to be enriched in spermatocytes and less in round spermati ds, but was undetectable in elongated spermatids by in situ hybridization. In addition, Amida protein was observed in the nucleus of spermatocytes and even in the elongated spermatids by immunohistochemistry. The development and cellular localization differences of Amida mRNA and protein implicates that Amida mRNA may undergo posttranscriptional regulation. Furthermore, Am ida mRNA decreased significantly in the 8-day experimental cryptorchid test is when spermatogenesis was disrupted. Taken together, these data suggest t hat Amida is involved in spermatogenesis and may play an important role in development of testicular germ cells. (C) 2001 Academic Press.