![Camera-based Measurements of Intracellular [Na+] in Murine Atrial Myocytes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59600.jpg&w=3840&q=50)
在NA的活动的变化
Keiko Mitsunaga-Nakatsubo1, Akiko Fujiwara1, Ikuo Yasumasu1
1Department of Biology, School of Education, Waseda University, 1-6-1, Nishiwaseda, Shinjuku-ku, Tokyo 169-50, Japan.
Development, growth & differentiation
|June 7, 2023
概括
- (Na+,K+-ATPase) 活动在海胚胎发育过程中增加,特别是在外皮细胞中. 这种增长取决于新的蛋白质合成和mRNA在胃流动之前的积累.
科学领域:
- 发展生物学 发展生物学
- 细胞生理学 细胞生理学
- 生物化学 生物化学
背景情况:
- 敏感于ouabain的Na+,K+-ATPase对于细胞离子运输和恒温至关重要.
- 了解胚胎早期发育过程中Na+,K+-ATPase的调节是理解细胞分化和组织形成的关键.
研究的目的:
- 为了研究海胚胎中Na+,K+-ATPase活性的发育变化.
- 确定胚胎发生过程中Na+,K+-ATPase的细胞局部化和调节机制.
主要方法:
- 在不同发育阶段的海胚胎 (未受精的卵子,乳头,游泳芽细胞,介质芽细胞,晚期胃细胞) 上进行了酶活性测定.
- 细胞分片被分离,以分析不同细胞系中的Na+,K+-ATPase活性 (胚胎壁与介质细胞/大介质细胞).
- 评估了循环赫西米德 (蛋白质合成抑制剂) 和actinomycin D (mRNA合成抑制剂) 对酶活性的影响.
主要成果:
- 从未受精的卵子到游泳芽细胞阶段,Na+,K+-ATPase活性保持不变,然后从中介质芽细胞到晚期胃细胞阶段显著增加.
- 活动的增加在胚胎壁细胞分数 (含有假定外皮细胞) 中比较明显,而不是介质细胞/骨干细胞分数.
- 循环赫西米德抑制了活性增加并降低了整体活性,而阿克丁诺米辛D在早期应用时阻止了活性增加,但在发育后期应用时效果较小.
结论:
- 在海胚胎发生过程中,Na+,K+-ATPase活性在发育过程中的增加主要在转录后或转化水平上受到调节,需要新的蛋白质合成.
- 编码Na+的mRNA,K+-ATPase可能在介质细胞爆发阶段之前积聚在外皮细胞中,并在早期胃细胞爆发阶段完成.
- 这些发现突显了Na+,K+-ATPase在外皮细胞分化和海发育过程中的功能中的特定作用.
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