Elucidating Abnormal RNA Modifications in Cancer

• Project/Area Number: 18K15123
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 49030:Experimental pathology-related
• Research Institution: Osaka University
• Principal Investigator: Kotaro Miyake 大阪大学, 大学院医学系研究科, 助教 (80726787)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥4,030,000 (Direct Cost: ¥3,100,000、Indirect Cost: ¥930,000); Fiscal Year 2021: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2020: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2018: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: RNA / METTL14 / c-MET / c-MYC / m6A / RNA修飾

Outline of Final Research Achievements

We conducted a study focusing on the METTL14 R298P mutation, a mutation hotspot in various types of cancer. By utilizing CRISPR-Cas9, we generated cell lines with this specific mutation and performed MeRIP-Seq analysis. Our findings revealed that the canonical m6A modification motif, 5'-AC-3', was altered to 5'-AU-3'. The m6A modification at the 5'-AU-3' motif appeared to have a minimal direct impact on gene expression, as it did not bind to reader proteins. However, we discovered that gene expression regulation occurred due to the modification of adjacent motifs when the aberrant motif was m6A-modified.

Academic Significance and Societal Importance of the Research Achievements

RNAのメチル化(m6A修飾は)は5'-(m6A)C-3'というモチーフに書き込まれており、幅広い遺伝子発現を制御するメカニズムである。今回の研究は①正しいモチーフにm6Aを書き込むためにはMETTL14 R298が重要であること ②正しくないモチーフに書き込まれたm6Aは機能を失うこと ③正しくないモチーフにm6Aが書き込まれる時に、周囲の正しいモチーフが副次的にm6A修飾されることによって遺伝子発現が調整されうること を明らかにした。