Marquez-Garcia Belen, Njo Maria, Beeckman Tom, Goormachtig Sofie, Foyer Christine H
Centre for Plant Sciences, Faculty of Biology, University of Leeds, Leeds, LS2 9JT, UK; Department of Plant Systems Biology, VIB, Ghent University, 9052, Gent, Belgium; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052, Gent, Belgium.
Plant Cell Environ. 2014 Feb;37(2):488-98. doi: 10.1111/pce.12172. Epub 2013 Aug 22.
Reduced glutathione (GSH) is required for root development, but its functions are not characterized. The effects of GSH depletion on root development were therefore studied in relation to auxin and strigolactone (SL) signalling using a combination of molecular genetic approaches and pharmacological techniques. Lateral root (LR) density was significantly decreased in GSH synthesis mutants (cad2-1, pad2-, rax1-), but not by the GSH synthesis inhibitor, buthionine sulfoximine (BSO). BSO-induced GSH depletion therefore did not influence root architecture in the same way as genetic impairment. Root glutathione contents were similar in the wild-type seedlings and max3-9 and max4-1 mutants that are deficient in SL synthesis and in the SL-signalling mutant, max2-1. BSO-dependent inhibition of GSH synthesis depleted the tissue GSH pool to a similar extent in the wild-type and SL synthesis mutants, with no effect on LR density. The application of the SL analogue GR24 increased root glutathione in the wild-type, max3-9 and max4-1 seedlings, but this increase was absent from max2-1. Taken together, these data establish a link between SLs and the GSH pool that occurs in a MAX2-dependent manner.
还原型谷胱甘肽（GSH）是根系发育所必需的，但其功能尚未明确。因此，利用分子遗传学方法和药理学技术相结合的手段，研究了GSH耗竭对根系发育的影响，并将其与生长素和独脚金内酯（SL）信号传导联系起来。在GSH合成突变体（cad2-1、pad2-、rax1-）中，侧根（LR）密度显著降低，但GSH合成抑制剂丁硫氨酸亚砜胺（BSO）并未导致这种降低。因此，BSO诱导的GSH耗竭对根系结构的影响与基因损伤不同。野生型幼苗以及缺乏SL合成的max3-9和max4-1突变体以及SL信号突变体max2-1中的根系谷胱甘肽含量相似。BSO对GSH合成的依赖性抑制在野生型和SL合成突变体中使组织GSH库减少到相似程度，对LR密度没有影响。SL类似物GR24的施用增加了野生型、max3-9和max4-1幼苗中的根系谷胱甘肽，但max2-1中没有这种增加。综上所述，这些数据建立了SL与以MAX2依赖方式发生的GSH库之间的联系。
