Development of a new in vitro differentiation system of conifer tracheids for analysis of cell wall formation

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K15882
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 40020:Wood science-related
• Research Institution: Hokkaido University
• Principal Investigator: Yamagishi Yusuke 北海道大学, 農学研究院, 助教 (80770247)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 仮道管 / 管状要素 / 二次木部細胞 / Picea abies / オーキシン / 針葉樹 / 植物組織培養

Outline of Final Research Achievements

More than 90% of conifer stems are composed of tracheids. Therefore, the morphology and cell wall structure of tracheids greatly affect the quality of soft wood. However, the mechanisms of differentiation and cell wall formation of tracheids have not been fully understood. Therefore, as a model for analyzing the cell wall formation process of tracheids, we developed an model differentiation system of tracheids using cultured cells of Norway Spruce. We have identified culture conditions to induce cultured cells stably divide and proliferate, and culture conditions to induce cells differentiate into cells with thickened cell walls at a high frequency. The cells with thickened cell walls showed structures very similar to the bordered pits found in tracheids. These results indicate that an experimental system for inducing tracheid-like cells from cultured cells of Norway Spruce has been established.

Free Research Field

樹木細胞生物学

Academic Significance and Societal Importance of the Research Achievements

木材などの木質バイオマスの循環型有効利用は、再生可能な資源エネルギーの供給に重要である。針葉樹材においては、仮道管の形態や細胞壁構造が針葉樹の材質に大きく影響する。仮道管の形成は樹幹の内部で起こるため、一つの生細胞の連続的な細胞壁の形成過程を解析することはできない。
今回開発された培養細胞を用いたモデル誘導系は、仮道管様の細胞の形成過程の連続的な解析を可能にしており、従来の誘導系と比較して誘導率や誘導方法の単純さ等に利点がある。本成果の活用によって仮道管の形成機構に関する情報の蓄積が進むことで、将来的な針葉樹材の材質制御を目的とした森林施業や育種選抜等の応用が期待できる。