Ufa Institute of Biology, Ufa Federal Research Centre, Russian Academy of Sciences, Prospekt Oktyabrya 69, 450054 Ufa, Russia.
Int J Mol Sci. 2023 Oct 13;24(20):15148. doi: 10.3390/ijms242015148.
Inhibition of root elongation is an important growth response to salinity, which is thought to be regulated by the accumulation of jasmonates and auxins in roots. Nevertheless, the mechanisms of the interaction of these hormones in the regulation of the growth response to salinity are still not clear enough. Their better understanding depends on the study of the distribution of jasmonates and auxins between root cells. This was achieved with the help of immunolocalization of auxin (indoleacetic acid) and jasmonates on the root sections of pea plants. Salinity inhibited root elongation and decreased the size of the meristem zone and the length of cells in the elongation zone. Immunofluorescence based on the use of appropriate, specific antibodies that recognize auxins and jasmonates revealed an increased abundance of both hormones in the meristem zone. The obtained data suggests the participation of either auxins or jasmonates in the inhibition of cell division, which leads to a decrease in the size of the meristem zone. The level of only auxin and not jasmonate increased in the elongation zone. However, since some literature evidence argues against inhibition of root cell division by auxins, while jasmonates have been shown to inhibit this process, we came to the conclusion that elevated jasmonate is a more likely candidate for inhibiting root meristem activity under salinity conditions. Data suggests that auxins, not jasmonates, reduce cell size in the elongation zone of salt-stressed plants, a suggestion supported by the known ability of auxins to inhibit root cell elongation.
根伸长的抑制是对盐度的重要生长反应，据认为这种抑制是由根中茉莉酸和生长素的积累所调节的。然而，这些激素在调节盐度生长反应中的相互作用机制还不够清楚。对这些机制的更好理解取决于对茉莉酸和生长素在根细胞之间分布的研究。这是通过对豌豆植株根切片中生长素（吲哚乙酸）和茉莉酸的免疫定位来实现的。盐度抑制根伸长，减少了顶端分生组织区的大小和伸长区细胞的长度。基于使用识别生长素和茉莉酸的适当特异性抗体的免疫荧光技术，揭示了两种激素在顶端分生组织区的丰度增加。所得数据表明，无论是生长素还是茉莉酸都参与了细胞分裂的抑制，从而导致顶端分生组织区的大小减小。只有生长素而不是茉莉酸在伸长区增加。然而，由于一些文献证据表明生长素不会抑制根细胞分裂，而茉莉酸已被证明会抑制这个过程，因此我们得出结论，在盐胁迫条件下，升高的茉莉酸更有可能是抑制根分生组织活性的候选物质。数据表明，生长素而不是茉莉酸减少了盐胁迫植物伸长区细胞的大小，这一观点得到了生长素抑制根细胞伸长的已知能力的支持。
