JXB Advance Access published online on September 22, 2007
Journal of Experimental Botany, doi:10.1093/jxb/erm152
RESEARCH PAPER |
Ferritins and nodulation in Lupinus luteus: iron management in indeterminate type nodules
1Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland
2Department of Botany, Faculty of Agriculture and Biology, Warsaw University of Life Sciences-SGGW, Nowoursynowska 159, 02-776 Warsaw, Poland
* To whom correspondence should be addressed. E-mail: spprom{at}ibch.poznan.pl
An ability to form symbiotic associations with rhizobia and to utilize atmospheric nitrogen makes legumes ecologically successful. High iron content in legume grains, partially relocated from root nodules, is another-nutritional-advantage of this group of plants. The ferritin complex is the major cell iron storage and detoxification unit and has been recognized as a marker of many stress-induced responses. The possible participation of ferritin in nodule formation and functioning was investigated here. Correlation of increased accumulation of both ferritin polypeptide and mRNA with actual in situ localization of ferritin allowed ferritin synthesis in the developing, indeterminate-type root nodules to be related to differentiating bacteroid tissue. This kind of tissue, in contrast to the determinate-type nodules, is present in lupin nodules at almost all stages of their development. Interestingly, it was found that, in this type of nodule, senescence starting in the decaying zones induces ferritin accumulation in younger, still active, tissues. Based on the presented data, and in correlation with previous results, some aspects of the regulation of expression of lupin ferritin genes are also discussed.
Key words: Biological nitrogen fixation, ferritin, indeterminate-type nodule, iron, oxidative stress, plant–microbe interactions
Received 2 May 2007; Revised 30 May 2007 Accepted 7 June 2007