Virus Research 188 (2014) 128–141 Contents lists available at ScienceDirect Virus Research j ourna l ho me pa g e: www.elsevier.com/locate/virusres Review Taxonomic reorganization of family Partitiviridae and other recent progress in partitivirus research Max L. Nibert a,∗ , Said A. Ghabrial b , Edgar Maiss c , Till Lesker c , Eeva J. Vainio d , Daohong Jiang e , Nobuhiro Suzuki f a Department of Microbiology & Immunobiology, Harvard Medical School, Boston, MA 02115, USA b Department of Plant Pathology, University of Kentucky, Lexington, KY 40546, USA c Department of Phytomedicine, Institute of Horticultural Production Systems, Leibniz Universität Hannover, Hannover D-30419, Germany d Finnish Forest Research Institute, Vantaa Research Unit, Vantaa, Finland e State Key Lab of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, Hubei Province, PR China f Institute of Plant Science & Resources, Okayama University, Kurashiki, Japan a r t i c l e i n f o Article history: Received 9 March 2014 Received in revised form 10 April 2014 Accepted 11 April 2014 Available online 21 April 2014 Keywords: dsRNA virus Fungal virus Plant virus Protozoal virus Partitivirus Partitiviridae Cryptovirus Virus taxonomy a b s t r a c t Phylogenetic analyses have prompted a taxonomic reorganization of family Partitiviridae (encapsidated, bisegmented dsRNA viruses that infect plants, fungi, or protozoa), the focus of this review. After a brief introduction to partitiviruses, the taxonomic changes are discussed, including replacement of former gen- era Partitivirus, Alphacryptovirus, and Betacryptovirus, with new genera Alphapartitivirus, Betapartitivirus, Gammapartitivirus, and Deltapartitivirus, as well as redistribution of species among these new genera. To round out the review, other recent progress of note in partitivirus research is summarized, including dis- coveries of novel partitivirus sequences by metagenomic approaches and mining of sequence databases, determinations of fungal partitivirus particle structures, demonstrations of fungal partitivirus transmis- sion to new fungal host species, evidence for other aspects of partitivirus–host interactions and host effects, and identification of other fungal or plant viruses with some similarities to partitiviruses. Some outstanding questions are also discussed. © 2014 Elsevier B.V. All rights reserved. Contents 1. Introduction to partitiviruses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129 2. Taxonomic reorganization of family Partitiviridae . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129 2.1. Taxonomic history, phylogenetic findings, and approved changes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129 2.2. Other supporting evidence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 2.3. Additional considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 3. Recent progress in partitivirus research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 3.1. Sequences from metagenomic approaches and database mining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 3.2. Particle structures of fungal partitiviruses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 3.3. Transmission of fungal partitiviruses to new fungal host species . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 3.4. Other aspects of partitivirus–host interactions and host effects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 3.5. New plant or fungal viruses with some similarities to partitiviruses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 4. Summary and questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 Appendix A. Supplementary data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 ∗ Corresponding author. Tel.: +1 617 4324829. E-mail address: mnibert@hms.harvard.edu (M.L. Nibert). http://dx.doi.org/10.1016/j.virusres.2014.04.007 0168-1702/© 2014 Elsevier B.V. All rights reserved.