Exosomes mediate horizontal transmission of viral pathogens from insect vectors to plant phloem.

Content Provider	Europe PMC
Author	Chen, Qian Liu, Yuyan Ren, Jiping Zhong, Panpan Chen, Manni Jia, Dongsheng Chen, Hongyan Wei, Taiyun
Editor	Monaghan, Jacqueline Weigel, Detlef
Copyright Year	2021
Abstract	Numerous piercing-sucking insects can horizontally transmit viral pathogens together with saliva to plant phloem, but the mechanism remains elusive. Here, we report that an important rice reovirus has hijacked small vesicles, referred to as exosomes, to traverse the apical plasmalemma into saliva-stored cavities in the salivary glands of leafhopper vectors. Thus, virions were horizontally transmitted with exosomes into rice phloem to establish the initial plant infection during vector feeding. The purified exosomes secreted from cultured leafhopper cells were enriched with virions. Silencing the exosomal secretion-related small GTPase Rab27a or treatment with the exosomal biogenesis inhibitor GW4869 strongly prevented viral exosomal release in vivo and in vitro. Furthermore, the specific interaction of the 15-nm-long domain of the viral outer capsid protein with Rab5 induced the packaging of virions in exosomes, ultimately activating the Rab27a-dependent exosomal release pathway. We thus anticipate that exosome-mediated viral horizontal transmission is the conserved strategy hijacked by vector-borne viruses.
Journal	eLife
Volume Number	10
PubMed Central reference number	PMC8253596
PubMed reference number	34214032
e-ISSN	2050084X
DOI	10.7554/elife.64603
Language	English
Publisher	eLife Sciences Publications, Ltd
Publisher Date	2021-07-02
Access Restriction	Open
Rights License	This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited. © 2021, Chen et al
Subject Keyword	exosome multivesicular bodies insect vectors salivary glands viral transmission plant phloem Virus
Content Type	Text
Resource Type	Article
Subject	Immunology and Microbiology Neuroscience Medicine Biochemistry, Genetics and Molecular Biology