The State Key Laboratory of Plant Cell & Chromosome Engineering, Center of Agricultural Research Resources, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 286 Huaizhong Road, Shijiazhuang, Hebei 050021, China.
Graduate University, Chinese Academy of Sciences, Beijing 100039, China.
New Phytol. 2011 Mar;189(4):1122-1134. doi: 10.1111/j.1469-8137.2010.03545.x. Epub 2010 Nov 18.
• The SOS signaling pathway plays an important role in plant salt tolerance. However, little is known about how the SOS pathway modulates organ development in response to salt stress. Here, the involvement of SOS signaling in NaCl-induced lateral root (LR) development in Arabidopsis was assessed. • Wild-type and sos3-1 mutant seedlings on iso-osmotic concentrations of NaCl and mannitol were analyzed. The marker lines for auxin accumulation, auxin transport, cell division activity and stem cells were also examined. • The results showed that ionic effect alleviates the inhibitory effects of osmotic stress on LR development. LR development of the sos3-1 mutant showed increased sensitivity specifically to low salt. Under low-salt conditions, auxin in cotyledons and LR primordia (LRP) of the sos3-1 mutant was markedly reduced. Decreases in auxin polar transport of mutant roots may cause insufficient auxin supply, resulting in defects not only in LR initiation but also in cell division activity in LRP. • Our data uncover a novel role of the SOS3 gene in modulation of LR developmental plasticity and adaptation in response to low salt stress, and reveal a new mechanism for plants to sense and adapt to small changes of salt.
• SOS 信号通路在植物耐盐性中起着重要作用。然而，对于 SOS 途径如何调节器官发育以响应盐胁迫知之甚少。本研究评估了 SOS 信号在 NaCl 诱导拟南芥侧根（LR）发育中的作用。 • 在等渗浓度的 NaCl 和甘露醇上分析野生型和 sos3-1 突变体幼苗。还检查了生长素积累、生长素运输、细胞分裂活性和干细胞的标记线。 • 结果表明，离子效应缓解了渗透压胁迫对 LR 发育的抑制作用。sos3-1 突变体的 LR 发育对低盐表现出更高的敏感性。在低盐条件下，sos3-1 突变体的子叶和 LR 原基（LRP）中的生长素明显减少。突变体根中生长素的极性运输减少可能导致生长素供应不足，不仅导致 LR 起始缺陷，而且导致 LRP 中的细胞分裂活性缺陷。 • 我们的数据揭示了 SOS3 基因在调节 LR 发育可塑性和适应低盐胁迫方面的新作用，并为植物感知和适应盐度的微小变化提供了新的机制。
