Maejima Eriko, Watanabe Toshihiro
a Research Faculty of Agriculture; Hokkaido University; Sapporo, Japan.
Plant Signal Behav. 2014;9(7):e29277. doi: 10.4161/psb.29277.
The negative charge on the plasma membrane (PM) is mainly derived from the phosphate group of phospholipids. One of the mechanisms of aluminum (Al) toxicity is to increase the PM permeability of root cells by binding to the negative sites on the PM. Thus, PM with a higher proportion of phospholipids could be more susceptible to Al toxicity. In our previous study, we showed that tolerance to Al and low-calcium in rice was enhanced by decreasing the proportion of phospholipids in root cells. Both Melastoma malabathricum L. and Melaleuca cajuputi Powell are dominant woody species that grow in tropical acid sulfate soils, and have been reported to be more tolerant to Al than rice. Surprisingly, the proportion of PM phospholipids in root cells of M. malabathricum and M. cajuputi was considerably low. Our present findings suggest that PM lipid composition plays an important role in Al tolerance mechanisms in various plant species.
质膜（PM）上的负电荷主要来源于磷脂的磷酸基团。铝（Al）毒性的机制之一是通过与质膜上的负性位点结合来增加根细胞的质膜通透性。因此，磷脂比例较高的质膜可能对铝毒性更敏感。在我们之前的研究中，我们发现通过降低根细胞中磷脂的比例可以增强水稻对铝和低钙的耐受性。桃金娘和白千层都是生长在热带酸性硫酸盐土壤中的优势木本物种，据报道它们比水稻更耐铝。令人惊讶的是，桃金娘和白千层根细胞质膜磷脂的比例相当低。我们目前的研究结果表明，质膜脂质组成在各种植物物种的耐铝机制中起着重要作用。
