Androgen receptors in a cichlid fish, Astatotilapia burtoni:: Structure, localization, and expression levels
Androgen receptors in a cichlid fish, Astatotilapia burtoni:: Structure, localization, and expression levels
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DOI：
10.1002/cne.21435
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发表时间：
2007-09-01
影响因子：
2.5
通讯作者：
Fernald, Russell D.
中科院分区：
文献类型：
--
作者：
Harbott, Lene K.;Burmeister, Sabrina S.;Fernald, Russell D.
雄激素是控制所有脊椎动物繁殖的下丘脑-垂体-性腺（HPG）轴的重要输出。在雄性硬骨鱼中，两种雄激素，睾酮和11-酮睾酮，控制幼体的性分化和发育以及成年体的生殖行为。雄激素信号在 HPG 轴的多个层面提供反馈，包括合成和释放促性腺激素释放激素 1 (GnRH1) 的下丘脑神经元，但雄激素在大脑中作用的精确细胞位点尚不清楚。在这里，我们描述了慈鲷Astatotilapia burtoni中的两种雄激素受体亚型，AR α和AR β，并表明这些亚型在成年大脑中不同地分布在已知具有控制繁殖功能的细胞核中。 ARα在腹侧端脑的腹侧部分、下丘脑的视前区(POA)和腹侧下丘脑表达，而ARβ在背侧和腹侧端脑、POA以及腹侧和背侧下丘脑中表达更广泛。我们在所有脊椎动物中首次提供了证据，证明释放 GnRH1 的神经元（作为 HPG 轴的中央控制点）表达 AR 的两种亚型。通过实时定量PCR，我们发现A.burtoni AR亚型在成体组织中具有不同的表达水平，其中ARα在垂体中的表达显着高于ARβ，并且AR在前脑和中脑中的表达水平高于ARa。这些数据为了解雄激素在调节脊椎动物生殖轴中的作用提供了重要的见解。 J.Comp。 (c) 威利利斯公司
Androgens are an important output of the hypothalamic-pituitary-gonadal (HPG) axis that controls reproduction in all vertebrates. In male teleosts two androgens, testosterone and 11-ketotestosterone, control sexual differentiation and development in juveniles and reproductive behavior in adults. Androgenic signals provide feedback at many levels of the HPG axis, including the hypothalamic neurons that synthesize and release gonadotropin-releasing hormone 1 (GnRH1), but the precise cellular site of androgen action in the brain is not known. Here we describe two androgen receptor subtypes, AR alpha and AR beta, in the cichlid Astatotilapia burtoni and show that these subtypes are differentially located throughout the adult brain in nuclei known to function in the control of reproduction. AR alpha was expressed in the ventral part of the ventral telencephalon, the preoptic area (POA) of the hypothalamus and the ventral hypothalamus, whereas AR beta was more widely expressed in the dorsal and ventral telencephalon, the POA, and the ventral and dorsal hypothalamus. We provide the first evidence in any vertebrate that the GnRH1-releasing neurons, which serve as the central control point of the HPG axis, express both subtypes of AR. Using quantitative real-time PCR, we show that A. burtoni AR subtypes have different expression levels in adult tissue, with AR alpha showing significantly higher expression than AR beta in the pituitary, and AR expressed at a higher level than ARa in the anterior and middle brain. These data provide important insight into the role of androgens in regulating the vertebrate reproductive axis. J. Comp. (c) Wiley-Liss, Inc.