An ancestral gibberellin biosynthetic pathway in the moss Physcomitrella patens

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K18693
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Bioorganic chemistry
• Research Institution: Keio University (2018); The University of Tokyo (2016-2017)
• Principal Investigator: Miyazaki Sho 慶應義塾大学, 理工学部(矢上), 助教 (30755955)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: ジテルペノイド / コケ植物 / ジベレリン / カウレン酸 / ヒメツリガネゴケ / 次世代シークエンサ

Outline of Final Research Achievements

The moss Physcomitrella patens does not respond to active GAs, and GAs have not been detected in the moss. However, P. patens has a partial GA biosynthetic pathway. Using biochemical approaches, we found that a KA-derived diterpenoid functions as a potent regulator of protonemal cell differentiation in the moss. Bioassay-guided exploration with a Ppcps/ks mutant led to the detection of a bioactive metabolite from KA, and its structure was elucidated as 3OHKA. Transcriptome analysis identified a gene involved in the oxidation of KA to 2OHKA, an inactive metabolite in cell differentiation. These results indicate that P. patens converts KA to an active form by 3-oxidation and to an inactive form by 2-oxidation, identifying a potential activation/inactivation system for GA biosynthesis in flowering plants.

Free Research Field

天然物化学

Academic Significance and Societal Importance of the Research Achievements

植物は普遍的に植物ホルモン類を生産し，生活環で利用していると考えられていた．しかし，ヒメツリガネゴケはGAを生産せず，3OHKAを利用していた．陸上植物の進化と成長制御機構の共進化に関する重要な知見が得られた．