Effects of aluminum on nucleoli in root tip cells and selected physiological and biochemical characters in Allium cepa var. agrogarum L

Rong Qin; Yunqiu Jiao; Shanshan Zhang; Wusheng Jiang; Donghua Liu
January 2010
BMC Plant Biology;2010, Vol. 10, p225
Academic Journal
Background: Increased Al concentration causes reduction of mitotic activity, induction of nucleolar alteration, increase of the production of ROS and alteration of several antioxidant enzyme activities in plant cells. Allium cepa is an excellent plant and a useful biomarker for environmental monitoring. Limited information is available about the effects of Al on nucleoli, antioxidant enzyme system, contents of MDA and soluble protein in A. cepa. Therefore, we carried out the investigation in order to better understand the effects of Al on the growth, nucleoli in root tip cells and selected physiological and biochemical characters. Results: The results showed that the root growth exposed to 50 μM Al was inhibited significantly. 50 μM Al could induce some particles of argyrophilic proteins scattered in the nuclei and extruded from the nucleoli into the cytoplasm. The nucleolus did not disaggregate normally and still remained its characteristic structure during metaphase. Nucleolar reconstruction was inhibited. 50 μM Al induced high activities of SOD and POD in leaves and roots significantly (P < 0.05) when compared with control, whereas the level of CAT was low significantly (P < 0.05). At 50 μM Al the content of MDA in leaves was high significantly (P < 0.05) at 9th day and in roots increased (P < 0.05) with prolonging the treatment time during 6-12 days. The soluble protein content in leaves treated with 50 μM Al was high significantly (P < 0.05) at 6th day and increased with prolonging the treatment time. Conclusions: We suggest that variations in nucleoli and the alterations of antioxidant enzyme activities, MDA and soluble protein contents in Allium cepa can serve as useful biomarkers, which can provide valuable information for monitoring and forecasting effects of exposure to Al in real scenarios conditions. Among the antioxidant enzymes SOD and POD appear to play a key role in the antioxidant defense mechanism under Al toxicity condition. Data from MDA concentration show that Al indirectly produces superoxide radicals, resulting in increased lipid peroxidative products and oxidative stress.


Related Articles

  • The perichromatin region of the plant cell nucleus is the area with the strongest co-localisation of snRNA and SR proteins. Niedojadło, Janusz; Mikulski, Zbigniew; Dełeńko, Konrad; Szmidt-Jaworska, Adriana; Smoliński, Dariusz; Epstein, Alan // Planta;Aug2012, Vol. 236 Issue 2, p715 

    The spatial organisation of the splicing system in plant cells containing either reticular ( Allium cepa) or chromocentric ( Lupinus luteus) nuclei was studied by immunolabelling of SR proteins, snRNA, and the PANA antigen, known markers for interchromatin granule clusters in mammalian cells....

  • Nucleolus: the fascinating nuclear body. Sirri, Valentina; Urcuqui-Inchima, Silvio; Roussel, Pascal; Hernandez-Verdun, Danièle // Histochemistry & Cell Biology;Jan2008, Vol. 129 Issue 1, p13 

    Nucleoli are the prominent contrasted structures of the cell nucleus. In the nucleolus, ribosomal RNAs are synthesized, processed and assembled with ribosomal proteins. RNA polymerase I synthesizes the ribosomal RNAs and this activity is cell cycle regulated. The nucleolus reveals the functional...

  • Estimation of Mutagenic Effect and Modifications of Mitosis by Silver Nanoparticles. Prokhorova, I.; Kibrik, B.; Pavlov, A.; Pesnya, D. // Bulletin of Experimental Biology & Medicine;Dec2013, Vol. 156 Issue 2, p255 

    We analyzed mutagenic and mitosis-modifying effects of silver nanoparticles (Allium test). Chromosome aberrations and laggings and micronuclei were simultaneously registered in the same sample. Mitotic and phase indexes were calculated. No mutagenic effects were detected after treatment with...

  • Standardization of bulb and root sample sizes for the Allium cepa test. Barbério, A.; Voltolini, J. C.; Mello, M. L. S. // Ecotoxicology;Apr2011, Vol. 20 Issue 4, p927 

    lthough the Allium cepa test has been widely used to identify potentially cytotoxic and genotoxic pollutants in aquatic environments, variable non-standardized choices have been made regarding the number of plant bulbs and roots analyzed. We propose numbers for bulbs and roots per bulb when...

  • hyalosome.  // Taber's Cyclopedic Medical Dictionary (2009);2009, Issue 21, p1100 

    A definition of the medical term "hyalosome," which refers to a faintly staining intranuclear structure that resembles a nucleolus, is presented.

  • micronucleus.  // Taber's Cyclopedic Medical Dictionary (2009);2009, Issue 21, p1464 

    A definition of the term "micronucleus," which refers to a small nucleus, is presented.

  • nucleolonema.  // Taber's Cyclopedic Medical Dictionary (2009);2009, Issue 21, p1601 

    A definition of the term "nucleolonema" is presented, referring to a fine network in the nucleolus of a cell.

  • nucleolus.  // Taber's Cyclopedic Medical Dictionary (2009);2009, Issue 21, p1601 

    An encyclopedia entry for "nucleolus" is presented, referring to a spherical structure in the nucleus of a cell made of DNA, RNA and protein.

  • The dynamic nature of the nuclear envelope. Arnone, James T; Walters, Alison D; Cohen-Fix, Orna // Nucleus (1949-1034);Jul/Aug2013, Vol. 4 Issue 4, p261 

    In eukaryotes, chromosomes are encased by a dynamic nuclear envelope. In contrast to metazoans, where the nuclear envelope disassembles during mitosis, many fungi including budding yeast undergo "closed mitosis," where the nuclear envelope remains intact throughout the cell cycle. Consequently,...


Read the Article


Sorry, but this item is not currently available from your library.

Try another library?
Sign out of this library

Other Topics