Miyado Kenji, Kang Woojin, Yamatoya Kenji, Hanai Maito, Nakamura Akihiro, Mori Toshiyuki, Miyado Mami, Kawano Natsuko
Department of Reproductive Biology, National Research Institute for Child Health and Development, 2-10-1 Okura, Setagaya, Tokyo, 157-8535, Japan.
Department of Perinatal Medicine and Maternal Care, National Center for Child Health and Development, 2-10-1 Okura, Setagaya, Tokyo, 157-8535, Japan.
J Plant Res. 2017 May;130(3):479-483. doi: 10.1007/s10265-017-0907-7. Epub 2017 Feb 3.
In multicellular organisms, cellular components are constantly translocated within cells and are also transported exclusively between limited cells, regardless of their physical distance. Exosomes function as one of the key mediators of intercellular transportation. External vesicles were identified 50 years ago in plants and now reconsidered to be exosome-like vesicles. Meanwhile, a well-known exosomal component, tetraspanin CD9, regulates sperm-egg fusion in mammals. A number of Arabidopsis tetraspanins are also expressed in reproductive tissues at fertilization, and are localized at the plasma membrane of protoplasts. Moreover, CD9-containing structures (or 'microexosomes') are released from mouse eggs during their maturation and promote the sperm-egg fusion. This phenomenon implies that two types of shared-component intercellular carriers might be released from multiple types of plant and animal cells, which widely regulate biological phenomena. We herein highlight their discrete structures, formation processes, and functions.
在多细胞生物中，细胞成分在细胞内不断转运，并且也仅在有限的细胞之间运输，而不管它们的物理距离如何。外泌体作为细胞间运输的关键介质之一发挥作用。50年前在植物中发现了细胞外囊泡，现在被重新认为是类外泌体囊泡。同时，一种著名的外泌体成分，四跨膜蛋白CD9，调节哺乳动物的精卵融合。许多拟南芥四跨膜蛋白在受精时也在生殖组织中表达，并定位于原生质体的质膜上。此外，含CD9的结构（或“微外泌体”）在小鼠卵成熟过程中从卵中释放出来，并促进精卵融合。这一现象表明，两种具有共同成分的细胞间载体可能从多种植物和动物细胞中释放出来，广泛调节生物学现象。我们在此强调它们的离散结构、形成过程和功能。
