Instituto de Biología Molecular y Celular de Plantas (CSIC-UPV), 46022 Valencia, Spain.
Plant Physiol Biochem. 2010 Jul;48(7):534-9. doi: 10.1016/j.plaphy.2010.01.011. Epub 2010 Jan 22.
Several pieces of evidence suggest a role for polyamines in the regulation of plant vascular development. For instance, polyamine oxidase gene expression has been shown to be associated with lignification, and downregulation of S-adenosylmethionine decarboxylase causes dwarfism and enlargement of the vasculature. Recent evidence from Arabidopsis thaliana also suggests that the active polyamine in the regulation of vascular development is the tetraamine thermospermine. Thermospermine biosynthesis is catalyzed by the aminopropyl transferase encoded by ACAULIS5, which is specifically expressed in xylem vessel elements. Both genetic and molecular evidence support a fundamental role for thermospermine in preventing premature maturation and death of the xylem vessel elements. This safeguard action of thermospermine has significant impact on xylem cell morphology, cell wall patterning and cell death as well as on plant growth in general. This manuscript reviews recent reports on polyamine function and places polyamines in the context of the known regulatory mechanisms that govern vascular development.
有几项证据表明多胺在植物血管发育的调节中起作用。例如，多胺氧化酶基因的表达已被证明与木质化有关，而 S-腺苷甲硫氨酸脱羧酶的下调会导致矮小和血管增大。最近来自拟南芥的证据还表明，在调节血管发育中起作用的活性多胺是四胺热稳定多胺。热稳定多胺的生物合成由 ACULIS5 编码的氨丙基转移酶催化，该酶在木质部导管分子中特异性表达。遗传和分子证据都支持热稳定多胺在防止木质部导管过早成熟和死亡方面的基本作用。热稳定多胺的这种保护作用对木质部细胞形态、细胞壁模式和细胞死亡以及植物的整体生长都有重大影响。本文综述了多胺功能的最新报告，并将多胺置于已知调节血管发育的调控机制的背景下。
