Department of Electromagnetic Field, Faculty of Electrical Engineering, Czech Technical University in Prague, Czech Republic.
J Theor Biol. 2011 Oct 7;286(1):31-40. doi: 10.1016/j.jtbi.2011.07.007. Epub 2011 Jul 20.
Microtubules are important structures in the cytoskeleton, which organizes the cell. Since microtubules are electrically polar, certain microtubule normal vibration modes efficiently generate oscillating electric field. This oscillating field may be important for the intracellular organization and intercellular interaction. There are experiments which indicate electrodynamic activity of variety of cells in the frequency region from kHz to GHz, expecting the microtubules to be the source of this activity. In this paper, results from the calculation of intensity of electric field and of radiated electromagnetic power from the whole cellular microtubule network are presented. The subunits of microtubule (tubulin heterodimers) are approximated by elementary electric dipoles. Mechanical oscillation of microtubule is represented by the spatial function which modulates the dipole moment of subunits. The field around oscillating microtubules is calculated as a vector superposition of contributions from all modulated elementary electric dipoles which comprise the cellular microtubule network. The electromagnetic radiation and field characteristics of the whole cellular microtubule network have not been theoretically analyzed before. For the perspective experimental studies, the results indicate that macroscopic detection system (antenna) is not suitable for measurement of cellular electrodynamic activity in the radiofrequency region since the radiation rate from single cells is very low (lower than 10⁻²⁰ W). Low noise nanoscopic detection methods with high spatial resolution which enable measurement in the cell vicinity are desirable in order to measure cellular electrodynamic activity reliably.
微管是细胞骨架的重要结构,它组织细胞。由于微管具有电极性,某些微管的正常振动模式能够有效地产生振荡电场。这个振荡场可能对细胞内组织和细胞间相互作用很重要。有实验表明,各种细胞在千赫兹到千兆赫兹的频率范围内都具有电动力学活性,这表明微管可能是这种活性的来源。本文介绍了从整个细胞微管网络的电场强度和辐射电磁功率的计算结果。微管的亚基(微管蛋白异二聚体)用基本电偶极子近似表示。微管的机械振动由调制亚基偶极矩的空间函数表示。围绕着振荡微管的场被计算为组成细胞微管网络的所有调制基本电偶极子的矢量叠加。整个细胞微管网络的电磁辐射和场特性以前没有进行过理论分析。对于预期的实验研究,结果表明,由于单个细胞的辐射率非常低(低于 10⁻²⁰ W),宏观检测系统(天线)不适合测量射频区域的细胞电动力学活性。为了可靠地测量细胞电动力学活性,需要具有高空间分辨率的低噪声纳米级检测方法,以便在细胞附近进行测量。