在精子生成过程中CREM功能的发育转换:从对抗剂到激活剂
N S Foulkes1, B Mellström, E Benusiglio
1Laboratoire de Génétique Moléculaire des Eucaryotes du CNRS, Strasbourg, France.
Nature
|January 2, 1992
概括
研究人员在成年丸中发现了一种新形式的CREM基因,称为CREM tau. 这种异型在精子发育过程中从抑制转变为激活基因表达,这对于男性生育至关重要.
科学领域:
- 生殖生物学 生殖生物学
- 分子遗传学 分子遗传学
- 细胞信号传递 细胞信号传递
背景情况:
- 精子发生是由 pituitary-hypothalamic轴和腺酸环酶信号调节的.
- 克雷姆基因产生替代拼接变异,调节cAMP转录反应.
研究的目的:
- 在成年哺乳动物丸中识别和描述新型CREM异型.
- 为了研究CREM异型体在精子生成过程中的功能作用.
主要方法:
- 在丸细胞中分析基因表达和拼接模式.
- 新型CREM异型的蛋白质域和转录活性的表征.
主要成果:
- 在成年丸中发现了一种新的CREM异型,CREM tau.
- 克雷姆具有两个富含谷氨胺的域,赋予了转录激活.
- 从包基阶段开始,CREM表达从前生细胞中的对抗体形式转换为激活体形式 (CREM tau).
结论:
- 发现CREM突出了它在调节精子发生过程中的基因表达中的关键作用.
- 切割依赖CREM的功能逆转是男性生殖细胞发育期间基因表达发育调节的关键机制.
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