Disarrangement of actin filaments and Ca(2+) gradient by CdCl(2) alters cell wall construction in Arabidopsis thaliana root hairs by inhibiting vesicular trafficking

作  者:Fan JL, Wei XZ, Wan LC, Zhang LY, Zhao XQ, Liu WZ, Hao HQ, Zhang HY
影响因子:2.677
刊物名称:Journal of Plant Physiology
出版年份:Jul 15 2011
卷:168  期:11  页码:1157-1167

论文摘要:

 Cadmium (Cd), one of the most toxic heavy metals, inhibits many cellular and physiological processes in plants. Here, the involvement of cytoplasmic Ca(2+) gradient and actin filaments (AFs) in vesicular trafficking, cell wall deposition and tip growth was investigated during root (hair) development of Arabidopsis thaliana in response to CdCl(2) treatment. Seed germination and root elongation were prevented in a dose- and time-dependent manner by CdCl(2) treatment. Fluorescence labelling and non-invasive detection showed that CdCl(2) inhibited extracellular Ca(2+) influx, promoted intracellular Ca(2+) efflux, and disturbed the cytoplasmic tip-focused Ca(2+) gradient. In vivo labelling revealed that CdCl(2) modified actin organization, which subsequently contributed to vesicle trafficking. Transmission electron microscopy revealed that CdCl(2) induced cytoplasmic vacuolization and was detrimental to organelles such as mitochondria and endoplasmic reticulum (ER). Finally, immunofluorescent labelling and Fourier transform infrared (FTIR) analysis indicated that configuration/distribution of cell wall components such as pectins and cellulose was significantly altered in response to CdCl(2). Our results indicate that CdCl(2) induces disruption of Ca(2+) gradient and AFs affects the distribution of cell wall components in root hairs by disturbing vesicular trafficking in A. thaliana.