Elucidation of the mechanism of cell death in long-lived cells in trees by induction of artificial heartwood formation

2014 Fiscal Year Final Research Report

• Project/Area Number: 25850121
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Wood science
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: NAKABA Satoshi 東京農工大学, (連合)農学研究科(研究院), 助教 (40627709)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 心材形成 / 放射柔細胞 / 細胞死 / イメージング / アガサレジノール / 核 / デンプン粒 / 遺伝子発現解析

Outline of Final Research Achievements

In the present study, we used model system for analyzing the process of artificially induced cell death that accompanies with synthesis of a kind of heartwood substances, agatharesinol, in Cryptomeria japonica. The timing of activation of primary and secondary metabolisms and cytological changes during cell death of ray parenchyma cells in this system was revealed. In addition, intact ray parenchyma cells in Populus were analyzed by molecular biological methods. We isolated full-length cDNAs of xylem cysteine peptidases (XCPs), which is a kind of important autolytic enzyme in programmed cell death of short-lived tracheary element, from P. sieboldii × P. grandidentata. Patterns of gene expression of XCPs in long-lived ray parenchyma cells in P. tremula × P. alba were analyzed by real-time PCR. Our result implies that autolysis of ray parenchyma cells might not be fully explained by dramatically enhanced expression of XCP genes just before their programmed death.

Free Research Field

木質科学