Departamento de Ecología y Genética Forestal, Instituto de Ciencias Forestales (ICIFOR), Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria-Consejo Superior de Investigaciones Científicas (INIA-CSIC), 28040 Madrid, Spain.
Departamento de Ciencias de la Vida, Universidad de Alcalá (UAH), 28805 Alcalá de Henares, Spain.
Int J Mol Sci. 2024 Sep 14;25(18):9926. doi: 10.3390/ijms25189926.
The maritime pine ( Ait.) is a highly valuable Mediterranean conifer. However, recurrent drought events threaten its propagation and conservation. populations exhibit remarkable differences in drought tolerance. To explore these differences, we analyzed stem transcriptional profiles of grafts combining genotypes with contrasting drought responses under well-watered and water-stress regimes. Our analysis underscored that drought tolerance is mainly associated with constitutively expressed genes, which vary based on genotype provenance. However, we identified key genes encoding proteins involved in water stress response, abscisic acid signaling, and growth control including a PHD chromatin regulator, a histone deubiquitinase, the ABI5-binding protein 3, and transcription factors from Myb-related, DOF NAC and LHY families. Additionally, we identified that drought-tolerant rootstock could enhance the drought tolerance of sensitive scions by regulating the accumulation of transcripts involved in carbon mobilization, osmolyte biosynthesis, flavonoid and terpenoid metabolism, and reactive oxygen species scavenging. These included genes encoding galactinol synthase, CBL-interacting serine/threonine protein kinase 5, BEL1-like homeodomain protein, dihydroflavonol 4-reductase, and 1-deoxy-D-xylulose-5-phosphate. Our results revealed several hub genes that could help us to understand the molecular and physiological response to drought of conifers. Based on all the above, grafting with selected drought-tolerant rootstocks is a promising method for propagating elite recalcitrant conifer species, such as .
地中海松（Ait.）是一种极具价值的地中海松属针叶树。然而，频繁发生的干旱事件威胁着它的繁殖和保护。不同的种群表现出显著的耐旱性差异。为了探索这些差异，我们分析了在充分供水和水分胁迫条件下结合耐旱性不同基因型的嫁接组合的茎转录谱。我们的分析强调，耐旱性主要与组成型表达的基因有关，这些基因因基因型的起源而异。然而，我们鉴定出了编码参与水分胁迫响应、脱落酸信号转导和生长调控的蛋白质的关键基因，包括一个 PHD 染色质调节因子、一个组蛋白去泛素化酶、ABI5 结合蛋白 3 以及 Myb 相关、DOF NAC 和 LHY 家族的转录因子。此外，我们发现耐旱性砧木可以通过调节与碳动员、渗透物合成、类黄酮和萜类代谢以及活性氧清除相关的转录物积累来增强敏感性接穗的耐旱性。这些包括编码半乳糖醇合酶、CBL 相互作用丝氨酸/苏氨酸蛋白激酶 5、BEL1 样同源域蛋白、二氢黄酮醇 4-还原酶和 1-脱氧-D-木酮糖-5-磷酸的基因。我们的研究结果揭示了几个枢纽基因，这有助于我们理解针叶树对干旱的分子和生理响应。基于以上所有结果，选择耐旱性砧木进行嫁接是繁殖优良抗性针叶树物种的一种有前途的方法，例如 。
