microRNA-152 Mediates DNMT1-Regulated DNA Methylation in the Estrogen Receptor α Gene
microRNA-152 Mediates DNMT1-Regulated DNA Methylation in the Estrogen Receptor α Gene
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丛枝菌根定殖改变苜蓿中镉的亚细胞分布和化学形态并抵抗镉毒性
DOI：
10.1371/journal.pone.0048669
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发表时间：
2012-01-25
期刊：
影响因子：
3.7
通讯作者：
Juo, Suh-Hang Hank
中科院分区：
文献类型：
--
作者：
Wang, Yung-Song;Chou, Wen-Wen;Juo, Suh-Hang Hank
一些植物可以耐受甚至解毒被重金属污染的土壤。这种解毒能力可能取决于植物吸收的金属的化学形式以及植物如何在其组织中分配毒素。这反过来又可能对植物补救产生重要影响。研究了丛枝菌根（AM）真菌根内球囊霉（Glomus intraradices）对苜蓿（Medicago sativa L.）生长在添加镉的土壤中。该真菌显着殖民苜蓿根种植后25天。在紫花苜蓿上定殖的G.镉污染土壤根内镉含量在25-60 d时为17%~ 69%，随后下降到43%。在20 mg·kg-1 Cd处理下，AM真菌处理的植株地上部生物量比未加AM真菌处理的植株地上部生物量增加了1.7倍。在Cd浓度为0.5、5和20 mg·kg-1的条件下，未接种AM真菌的苜蓿地上部Cd浓度分别是接种AM真菌的1.87、2.92和2.38倍。真菌接种增加镉（37.2-80.5%），在根和芽细胞壁和细胞膜培养80天后相比，未处理的植物。在根中的非活性形式的镉的比例高于真菌处理的植物比对照。此外，虽然真菌处理的植物有较少的整体镉在亚细胞片段在芽，他们有更多的不活跃的镉在芽比对照植物。这些结果为进一步研究重金属污染土壤中的植物-微生物共生关系提供了基础，这可能有助于我们制定植物修复的管理制度。
Some plants can tolerate and even detoxify soils contaminated with heavy metals. This detoxification ability may depend on what chemical forms of metals are taken up by plants and how the plants distribute the toxins in their tissues. This, in turn, may have an important impact on phytoremediation. We investigated the impact of arbuscular mycorrhizal (AM) fungus, Glomus intraradices, on the subcellular distribution and chemical forms of cadmium (Cd) in alfalfa (Medicago sativa L.) that were grown in Cd-added soils. The fungus significantly colonized alfalfa roots by day 25 after planting. Colonization of alfalfa by G. intraradices in soils contaminated with Cd ranged from 17% to 69% after 25–60 days and then decreased to 43%. The biomass of plant shoots with AM fungi showed significant 1.7-fold increases compared to no AM fungi addition under the treatment of 20 mg·kg−1 Cd. Concentrations of Cd in the shoots of alfalfa under 0.5, 5, and 20 mg·kg−1 Cd without AM fungal inoculation are 1.87, 2.92, and 2.38 times higher, respectively, than those of fungi-inoculated plants. Fungal inoculation increased Cd (37.2–80.5%) in the cell walls of roots and shoots and decreased in membranes after 80 days of incubation compared to untreated plants. The proportion of the inactive forms of Cd in roots was higher in fungi-treated plants than in controls. Furthermore, although fungi-treated plants had less overall Cd in subcellular fragments in shoots, they had more inactive Cd in shoots than did control plants. These results provide a basis for further research on plant-microbe symbioses in soils contaminated with heavy metals, which may potentially help us develop management regimes for phytoremediation.