植物におけるポリアミン研究の現状

抄録

Polyamines (PAs) are aliphatic compounds with low molecular masses. The major PAs are the diamine putrescine, the triamine spermidine, and the tetraamines, spermine and thermospermine in plants. PAs play crucial roles not only in growth, development and longevity but also in adaptive responses against abiotic and biotic stresses. In the last decade information on plant PAs has been accumulated. Here I summarize the current state of knowledge, with a focus on polyamine synthesis and catabolism pathways, and introduce the evidence that putrescine and spermidine are essential for plant growth. Lastly I describe that all the Arabidopsis loss-of-function mutants which are involved in thermospermine metabolism display growth defect. Therefore I further discuss the importance of thermospermine homeostasis in this organism.