Elucidation of molecular basis regulation mechanism for serine biosynthesis in plant

2016 Fiscal Year Final Research Report

• Project/Area Number: 26870855
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Plant nutrition/Soil science; Applied biochemistry
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: OKAMURA EIJI 国立研究開発法人理化学研究所, 環境資源科学研究センター, 特別研究員 (90604398)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: Plant / Arabidopsis / Serine / Allosteric / Oryza / Physcomitrella / Homocysteine

Outline of Final Research Achievements

3-Phosphoglycerate dehydrogenase (PGDH) is the first committed enzyme of the phosphorylated pathway of serine biosynthesis, and is regulated by negative feedback from serine in bacteria and plants.
In the present study, some PGDH isoforms from Arabidopsis thaliana, Oryza sativa and Physcomitrella patens were inhibited by serine but were activated by homocysteine, methionine, alanine, valine and homoserine in vitro. Activation and inhibition by these amino acids was cooperative, suggesting an allosteric mechanism. Moreover, homocysteine was 2 orders of magnitude lower than that of the other effector amino acids, suggesting greater regulatory potency. These are the first data to show that PGDH from plants are activated by various biomolecules and indicate that serine biosynthesis in plant is regulated by multiple pathways.

Free Research Field

生化学