CICS-UBI Health Sciences Research Center, University of Beira Interior, Avenida Infante D. Henrique, 6200-506 Covilhã, Portugal.
Reproduction. 2011 Sep;142(3):447-56. doi: 10.1530/REP-11-0085. Epub 2011 Jun 16.
Regucalcin (RGN) is a calcium (Ca(2)(+))-binding protein which regulates intracellular Ca(2)(+) homeostasis by modulating the activity of enzymes regulating Ca(2)(+) concentration and enhancing Ca(2)(+)-pumping activity. Several studies have described the pivotal role of proper Ca(2)(+) homeostasis regulation to spermatogenesis and male fertility. Recently, RGN was identified as a sex steroid-regulated gene in prostate and breast; however, a possible role of RGN in spermatogenesis has not been examined. In this study, the expression and localization of RGN in rat and human testis, and other rat reproductive tissues was analyzed. Moreover, we studied whether RGN protein was present in seminiferous tubule fluid (STF). Finally, we examined the effect of 5α-dihydrotestosterone (DHT) on the expression of Rgn mRNA in rat seminiferous tubules (SeT) cultured ex vivo. The results presented in this study show that RGN is expressed in Leydig and Sertoli cells, as well as in all types of germ cells of both rat and human testis. RGN is also expressed in rat prostate, epididymis, and seminal vesicles. Moreover, RGN protein is present in rat STF. The results also demonstrate that Rgn expression is age dependent in rat testis, and is upregulated by the non-aromatizable androgen DHT in rat SeT cultured ex vivo. Taken together, these findings indicate that Rgn is a novel androgen-target gene in rat testis and that it may have a role in male reproductive function, particularly in the control of spermatogenesis.
Regucalcin（RGN）是一种钙（Ca(2)(+))结合蛋白，通过调节调节 Ca(2)(+)浓度的酶的活性和增强 Ca(2)(+)泵活性来调节细胞内 Ca(2)(+)稳态。几项研究描述了适当的 Ca(2)(+)稳态调节对精子发生和男性生育力的关键作用。最近，RGN 被鉴定为前列腺和乳腺中受性激素调节的基因；然而，RGN 在精子发生中的可能作用尚未被研究。在这项研究中，分析了 RGN 在大鼠和人睾丸以及其他大鼠生殖组织中的表达和定位。此外，我们研究了 RGN 蛋白是否存在于曲细精管液（STF）中。最后，我们研究了 5α-二氢睾酮（DHT）对大鼠曲细精管（SeT）离体培养中 Rgn mRNA 表达的影响。本研究结果表明，RGN 在大鼠和人睾丸的 Leydig 和 Sertoli 细胞以及所有类型的生殖细胞中表达。RGN 也在大鼠前列腺、附睾和精囊表达。此外，RGN 蛋白存在于大鼠 STF 中。研究结果还表明，Rgn 在大鼠睾丸中的表达具有年龄依赖性，并在大鼠 SeT 离体培养中被非芳香化雄激素 DHT 上调。总之，这些发现表明 Rgn 是大鼠睾丸中的一种新型雄激素靶基因，它可能在男性生殖功能中发挥作用，特别是在控制精子发生方面。
