The change of the ghrelin system in the evolution model animals of amphibious vertebrate which moved ashore from the water

2016 Fiscal Year Final Research Report

• Project/Area Number: 26440174
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Morphology/Structure
• Research Institution: National Cardiovascular Center Research Institute
• Principal Investigator: Kaiya Hiroyuki 国立研究開発法人国立循環器病研究センター, 研究所, 室長 (40300975)
• Co-Investigator(Renkei-kenkyūsha): KANGAWA Kenji 国立研究開発法人国立循環器病研究センター研究所, 所長 (00112417) ; KONNO Norifumi 富山大学, 理工学部, 講師 (50507051)
• Research Collaborator: HIRAOKA Kiyoshi 株式会社フジキン
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: グレリン / GHS-R / 機能解析 / 摂食量 / 浸透圧調節 / エネルギー代謝 / 遺伝子発現

Outline of Final Research Achievements

We determined the nucleotide sequence of the ghrelin precursor of a sturgeon (vestel) and structure of the mature ghrelin, and noticed that two kinds of mature ghrelin were produced from different mRNAs in the same individuals. In addition, we clarified that expression of the ghrelin gene increases as the development progresses from fertilized egg. Furthermore, we identified a functional ghrelin receptor (GHS-R) in the African lungfish, and it expresses in the brain, heart and intestines, and suggested the possibility to participate in osmoregulation and energy metabolism during the estivation. Moreover, two kinds of GHS-R that we discovered in axolotls varied in tissue distribution and expression level, and it was suggested that there was plural GHS-Rs in amphibians. In the fire belly newt and the Western clawed frog, intraperitoneal injection of the ghrelin did not affect the food intake.

Free Research Field

比較内分泌学