title: A phloem-limited fijivirus induces the formation of neoplastic phloem tissues that house virus multiplication in the host plant.
abstract: A number of phloem-limited viruses induce the development of tumours (enations) in the veins of host plants, but the relevance of tumour induction to the life cycle of those viruses is unclear. In this study, we performed molecular and structural analyses of tumours induced by rice black-streaked dwarf virus (RBSDV, genus Fijivirus) infection in maize plants. The transcript level of the maize cdc2 gene, which regulates the cell cycle, was highly elevated in tumour tissues. Two-dimensional electrophoresis identified 25 cellular proteins with altered accumulation in the tumour tissues. These proteins are involved in various metabolic pathways, including photosynthesis, redox, energy pathways and amino acid synthesis. Histological analysis indicated that the tumours predominantly originated from hyperplastic growth of phloem, but those neoplastic tissues have irregular structures and cell arrangements. Immunodetection assays and electron microscopy observations indicated that in the shoots, RBSDV is confined to phloem and tumour regions and that virus multiplication actively occurs in the tumour tissue, as indicated by the high accumulation of non-structural proteins and formation of viroplasms in the tumour cells. Thus, the induction of tumours by RBSDV infection provides a larger environment that is favourable for virus propagation in the host plant.
authors.affiliation: Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, P. R. China.
authors.forename: Jiangfeng
authors.initials: J
authors.lastname: Shen
authors.affiliation: Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, P. R. China.
authors.forename: Xian
authors.initials: X
authors.lastname: Chen
authors.affiliation: Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, P. R. China.
authors.forename: Jianping
authors.initials: J
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Crop Stress Biology for Arid Areas and College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, 712100, China.|Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, P. R. China.
authors.forename: Liying
authors.initials: L
authors.lastname: Sun
mesh_terms: D018506:Gene Expression Regulation, Plant; D012275:Oryza / Q000821:virology; D052585:Phloem / Q000235:genetics* / Q000821:virology; D010935:Plant Diseases / Q000235:genetics* / Q000821:virology; D010940:Plant Proteins / Q000235:genetics; D010941:Plant Tumors / Q000235:genetics* / Q000821:virology; D012087:Reoviridae / Q000235:genetics / Q000472:pathogenicity; D014779:Virus Replication / Q000235:genetics; D003313:Zea mays / Q000235:genetics* / Q000821:virology
chemical_list: D010940:Plant Proteins