Changes in the dielectric properties of medaka fish embryos during development, studied by electrorotation
Changes in the dielectric properties of medaka fish embryos during development, studied by electrorotation
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通过电旋转研究青鳉鱼胚胎在发育过程中介电特性的变化
DOI：
10.1016/j.bbrc.2012.10.019
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发表时间：
2012
影响因子：
3.1
通讯作者：
Günter R. Fuhr, Heiko Zimmermann，Vladimir L. Sukhorukov
中科院分区：
文献类型：
--
作者：
Ryo Shirakashi;Miriam Mischke;Peter Fischer;Simon Memmel;Georg Krohne;Günter R. Fuhr, Heiko Zimmermann，Vladimir L. Sukhorukov
在发育生物学和遗传学方面，日本青竹鱼已成为一种强大的脊椎动物模式生物。本研究通过电旋转(ROT)技术研究青竹胚胎在孵化前发育过程中的介电特性。由于其层状结构，青竹卵在khz-mhz频率范围内表现出多达三个腐烂峰。从囊胚到体节早期发育过程中，腐烂光谱变化不大。但随着胚胎发育到体节晚期，腐烂峰的频率和幅度发生了显著的变化。利用光学和电子显微镜获得的形态数据，我们用三壳介电模型分析了ROT光谱，该模型解释了主要的胚胎隔室。分析得出了蛋壳(绒毛膜)离子电导率的很高值，这一点得到了独立渗透实验的证实。透射电子显微镜显示，卵黄膜的电容相对较低，与其双层膜结构相一致。去卵黄的死卵只有一个同场腐烂峰，相对于活胚胎的相应峰明显向低频率移动。介电数据可能有助于在基础研究和工厂化水产养殖中监测鱼类胚胎活力/条件的发展和变化。
The Japanese medaka fish, Oryzias latipes, has become a powerful vertebrate model organism in developmental biology and genetics. The present study explores the dielectric properties of medaka embryos during pre-hatching development by means of the electrorotation (ROT) technique. Due to their layered structure, medaka eggs exhibited up to three ROT peaks in the kHz–MHz frequency range. During development from blastula to early somite stage, ROT spectra varied only slightly. But as the embryo progressed to the late-somite stage, the ROT peaks underwent significant changes in frequency and amplitude. Using morphological data obtained by light and electron microscopy, we analyzed the ROT spectra with a three-shell dielectric model that accounted for the major embryonic compartments. The analysis yielded a very high value for the ionic conductivity of the egg shell (chorion), which was confirmed by independent osmotic experiments. A relatively low capacitance of the yolk envelope was consistent with its double-membrane structure revealed by transmission electron microscopy. Yolk-free dead eggs exhibited only one co-field ROT peak, shifted markedly to lower frequencies with respect to the corresponding peak of live embryos. The dielectric data may be useful for monitoring the development and changes in fish embryos’ viability/conditions in basic research and industrial aquaculture.