Şekerci Keriman, Higashitani Nahoko, Ozgur Rengin, Higashitani Atsushi, Turkan Ismail, Uzilday Baris
Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan; Department of Biology, Faculty of Science, Ege University, Izmir, Türkiye.
Graduate School of Life Sciences, Tohoku University, Sendai, 980-8577, Japan.
Plant Physiol Biochem. 2025 Mar;220:109517. doi: 10.1016/j.plaphy.2025.109517. Epub 2025 Jan 17.
Salinization is a significant global issue causes irreversible damage to plants by reducing osmotic potential, inhibiting seed germination, and impeding water uptake. Seed germination, a crucial step towards the seedling stage is regulated by several hormones and genes, with the balance between abscisic acid and gibberellin being the key mechanism that either promotes or inhibits this process. Additionally, mucilage, a gelatinous substance, is known to provide protection against drought, herbivory, soil adhesion, and seed sinking. However, limited information is available on the structure and thickness of seed mucilage in halophytes under different salinity conditions. In this study, the mucilage structure of the extreme halophyte Schrenkiella parvula was compared with the glycophyte Arabidopsis thaliana in response to salinity. We found differences in the expression levels of genes such as ABI5, RGL2, DOG1, ENO2, and DHAR2, which are involved in seed germination and antioxidant activity, as well as in the mucilage structure of seeds of S. parvula and A. thaliana seeds at different salt concentrations. The responses of seed germination of S. parvula to salinity indicate that it is more salt-tolerant than A. thaliana. Additionally, it was found that S. parvula mucilage decreased under salt conditions but not under mannitol conditions, whereas in A. thaliana mucilage did not change under both conditions, which is one of the adaptation strategies of S. parvula to salt conditions. We believe that these fundamental analyzes will provide a foundation for future molecular and biochemical studies comparing the responses of crops and halophytes to salinity stress.
盐渍化是一个重大的全球性问题，它通过降低渗透势、抑制种子萌发和阻碍水分吸收对植物造成不可逆转的损害。种子萌发是迈向幼苗阶段的关键步骤，受多种激素和基因调控，脱落酸和赤霉素之间的平衡是促进或抑制这一过程的关键机制。此外，黏液是一种凝胶状物质，已知能提供抗旱、抗食草动物、土壤黏附及种子下沉保护。然而，关于不同盐度条件下盐生植物种子黏液的结构和厚度的信息有限。在本研究中，比较了极端盐生植物小盐芥与甜土植物拟南芥在盐胁迫下的黏液结构。我们发现参与种子萌发和抗氧化活性的ABI5、RGL2、DOG1、ENO2和DHAR2等基因的表达水平存在差异，以及不同盐浓度下小盐芥和拟南芥种子的黏液结构也不同。小盐芥种子萌发对盐度的反应表明它比拟南芥更耐盐。此外，发现小盐芥的黏液在盐处理条件下减少，但在甘露醇处理条件下不减少，而拟南芥的黏液在这两种条件下均未改变，这是小盐芥对盐条件的适应策略之一。我们相信这些基础分析将为未来比较作物和盐生植物对盐胁迫反应的分子和生化研究提供基础。
