棒光受体细胞的核架构适应了哺乳动物进化中的视觉
Irina Solovei1, Moritz Kreysing, Christian Lanctôt
1Division of Anthropology and Human Genetics, Biocenter, Ludwig-Maximilians University Munich, Grosshadernerstrasse 2, 82152 Planegg-Martinsried, Germany.
Cell
|April 22, 2009
概括
夜行哺乳动物的棒光受体细胞具有反转的核结构,与昼行哺乳动物不同. 这种独特的结构有效地引导光线,在低光条件下优化视力.
科学领域:
- 细胞生物学 细胞生物学
- 眼科医生 眼科 眼科
- 遗传学 是一个遗传学.
背景情况:
- 核架构,核中的染色体的空间组织,对于基因调节和细胞功能至关重要.
- 棒光受体细胞对于视力至关重要,特别是在低光环境中.
- 细胞通常表现出常规的核组织,异色素蛋白位于外围,而欧色素蛋白位于中心.
研究的目的:
- 研究和比较昼夜哺乳动物中杆光受体细胞的核结构.
- 阐明棒细胞中不同核模式的功能含义.
- 了解不同核组织的进化优势.
主要方法:
- 从昼夜哺乳动物的杆光受体细胞中核结构的比较分析.
- 显微镜技术可视化核组织,异色染色素和真色染色素的分布.
- 计算机模拟以模拟杆核的光通道.
主要成果:
- 日常哺乳动物在杆细胞中具有常规的核结构,具有外围的异色素和内部的 euchromatin.
- 夜行哺乳动物在杆细胞中表现出一个反转的核模式,其中有中心的异色染色素和外围的欧色染色素,新生的转录和拼接机械.
- 倒置模式是由于棒细胞分化过程中常规模式的重塑而产生的.
- 计算机模拟表明,反转的核结构起到收集镜头的作用,有效地将光线引导到杆子的外部段.
结论:
- 棒光受体的核架构在夜间哺乳动物和白天哺乳动物之间存在根本的差异,夜间哺乳动物表现出独特的反转模式.
- 夜行哺乳动物的这种反向核组织增强了捕捉光的功能,这对于在低光条件下对视力至关重要.
- 在大多数真核细胞中,传统的核结构可能是最受欢迎的,因为它在染色体排列和核功能调节方面的灵活性.
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