Journal of Plant Research

, Volume 130, Issue 3, pp 475–478 | Cite as

Novel insights into the molecular mechanism of sperm–egg fusion via IZUMO1

  • Naokazu Inoue
JPR Symposium Fusion in Fertilization: Interdisciplinary Collaboration among Plant and Animal Scientists


When a spermatozoon fertilizes an oocyte in mammals, there must be an extremely precise regulation system for successful gamete fusion to occur, which is the final step of fertilization. Using gene-modified animals, IZUMO1 on the sperm side and its receptor, JUNO, on the ovum side, have been unveiled as indispensable factors for triggering membrane fusion. We recently analyzed the detailed molecular machinery of the IZUMO1–JUNO recognition system and clarified the tertiary architecture of the IZUMO1–JUNO complex based on the crystal structure. Over the past 2 years, important discoveries have successively emerged, presenting a new perspective on fertilization. In this mini-review, I will initially explain the historical background of the molecular mechanism study of gamete fusion, and go on to describe our latest study data.


Fertilization Gamete fusion IZUMO1 JUNO 



This work was supported by JSPS KAKENHI Grant Number JP26291052 and the Takeda Science Foundation.


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Copyright information

© The Botanical Society of Japan and Springer Japan 2016

Authors and Affiliations

  1. 1.Department of Cell Science, School of Medicine, Institutes for Biomedical SciencesFukushima Medical UniversityFukushima-CityJapan

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