Effects of Lead on the Morphology and Structure of the Nucleolus in the Root Tip Meristematic Cells of Allium cepa L.

International Journal of Molecular Sciences

Ze Jiang¹  Huaning Zhang¹  Rong Qin¹  Jinhua Zou¹  Junran Wang¹  Qiuyue Shi¹  Wusheng Jiang¹ 

[1] Tianjin Key Laboratory of Animal and Plant Resistance, College of Life Sciences, Tianjin Normal University, Tianjin 300387, China; E-Mails:

关键词: Allium cepa var. agrogarum L.;    lead (Pb);    nucleolus;    nucleophosmin;    nucleolin;    fibrillarin;   

DOI  :  10.3390/ijms150813406

来源: mdpi

【 摘 要 】

To study the toxic mechanisms of lead (Pb) in plants, the effects of Pb on the morphology and structure of the nucleolus in root tip meristematic cells of Allium cepa var. agrogarum L. were investigated. Fluorescence labeling, silver-stained indirect immunofluorescent microscopy and western blotting were used. Fluorescence labeling showed that Pb ions were localized in the meristematic cells and the uptake and accumulation of Pb increased with treatment time. At low concentrations of Pb (1–10 μM) there were persistent nucleoli in some cells during mitosis, and at high concentration (100 μM) many of the nucleolar organizing regions were localized on sticky chromosomes in metaphase and anaphase cells. Pb induced the release of particles containing argyrophilic proteins to be released from the nucleus into the cytoplasm. These proteins contained nucleophosmin and nucleolin. Pb also caused the extrusion of fibrillarin from the nucleus into the cytoplasm. Western blotting demonstrated the increased expression of these three major nucleolar proteins under Pb stress.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.