Roles of fast-type skeletal muscle-specific microRNA

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K07775
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Integrative animal science
• Research Institution: National Agriculture and Food Research Organization
• Principal Investigator: MUROYA Susumu 国立研究開発法人農業・食品産業技術総合研究機構, 畜産研究部門, ユニット長 (50355062)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: ウシ / 骨格筋 / microRNA

Outline of Final Research Achievements

We clarified relationship between miR-196a and myosin heavy chain (MyHC) isoform expression in bovine masseter (MS), diaphragm (DP), semispinalis (SP), semitendinosus (ST), and longissimus dorci (LD) muscles, to investigate roles of miR-196a in bovine muscle type specification. The quantitative RT-PCR results showed that miR-196a is exclusively expressed in MyHC-2x isoform-abundant ST and LD muscles compared to the others (P < 0.001). The expression of miR-196a was correlated with those of MyHC-2x isoform (r = 0.738) and MyHC-slow (r = -0.764). These results revealed that miR-196a expression is highly associated with muscle type that is determined by MyHC isoform expression in bovine skeletal muscles.

Free Research Field

畜産

Academic Significance and Societal Importance of the Research Achievements

本研究では、ウシ骨格筋の速筋型筋線維におけるmiR-196aの特異性が明らかになったことから、miR-196aが速筋型筋線維のマーカーとして活用が可能であり、家畜育種選抜指標の開発にもつながると期待できる。また、速筋型と遅筋型の骨格筋では、互いに肉質（やわらかさ、色調、多汁性等）が異なり、速筋型の筋線維径は遅筋型より大きい等の違いもあるため、それぞれの筋線維型特性に関わるmicroRNAの存在様式の解明の意義は大きい。microRNA制御により筋線維型調節が可能になれば家畜の骨格筋形成を介した肉質・肉量の向上も将来的に期待できる。