Elucidation of cellular environment-sensing mechanism involving upstream ORFs and its application to genome breeding

2022 Fiscal Year Final Research Report

• Project/Area Number: 19H02917
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 38060:Applied molecular and cellular biology-related
• Research Institution: Hokkaido University
• Principal Investigator: Onouchi Hitoshi 北海道大学, 農学研究院, 教授 (50322839)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 上流ORF / リボソーム / ストレス応答 / 新生鎖

Outline of Final Research Achievements

Upstream open reading frames (uORFs) are elements found in the 5'-untranslated regions of eukaryotic transcripts that can affect translation of the downstream protein-coding sequences. In this study, we discovered that during translation of the uORF of an Arabidopsis gene, the translation complex containing the uORF-encoded nascent peptide directly senses magnesium to cause ribosome stalling, thereby repressing translation of the protein-coding sequence. Our results demonstrated that this magnesium-responsive translational regulation contributes to maintaining magnesium homeostasis in plant cells. Additionally, we identified a non-AUG-initiated uORF involved in the feedback regulation of the expression of a key enzyme of polyamine biosynthesis in plants.

Free Research Field

分子生物学

Academic Significance and Societal Importance of the Research Achievements

本研究により、マグネシウムやポリアミンの細胞内濃度を感知して恒常性を維持するための新たな機構が発見された。マグネシウムは植物の生育に必要な多量要素の一つであり、ポリアミンは植物の環境ストレス耐性に関与することが知られている。したがって、本研究の発見は植物生理学や分子生物学の分野に学術的なインパクトを与えるだけでなく、将来的には栄養欠乏環境やストレス環境における作物の生育改善などの応用につながることが期待できる。