title: Identification and molecular characterization of a novel monopartite geminivirus associated with mulberry mosaic dwarf disease.
abstract: High-throughput sequencing of small RNAs allowed the identification of a novel DNA virus in a Chinese mulberry tree affected by a disease showing mosaic and dwarfing symptoms. Rolling-circle amplification and PCR with specific primers, followed by sequencing of eleven independent full-length clones, showed that this virus has a monopartite circular DNA genome (∼ 2.95 kb) containing ORFs in both polarity strands, as reported previously for geminiviruses. A field survey showed the close association of the virus with diseased mulberries, so we tentatively named the virus mulberry mosaic dwarf-associated virus (MMDaV). The MMDaV genome codes for five and two putative proteins in the virion-sense and in the complementary-sense strands, respectively. Although three MMDaV virion-sense putative proteins did not share sequence homology with any protein in the databases, functional domains [coiled-coil and transmembrane (TM) domains] were identified in two of them. In addition, the protein containing a TM domain was encoded by an ORF located in a similar genomic position in MMDaV and in several other geminiviruses. As reported for members of the genera Mastrevirus and Becurtovirus, MMDaV replication-associated proteins are expressed through the alternative splicing of an intron, which was shown to be functional in vivo. A similar intron was found in the genome of citrus chlorotic dwarf-associated virus (CCDaV), a divergent geminivirus found recently in citrus. On the basis of pairwise comparisons and phylogenetic analyses, CCDaV and MMDaV appear to be closely related to each other, thus supporting their inclusion in a putative novel genus in the family Geminiviridae.
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, PR China.
authors.forename: Yuxin
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Istituto per la Protezione Sostenibile delle Piante CNR, UO Bari, Via Amendola, 70126 Bari, Italy.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Navarro
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, PR China.
authors.forename: Zhixiang
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, PR China.
authors.forename: Meiguang
authors.initials: M
authors.lastname: Lu
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, PR China.
authors.forename: Xueping
authors.initials: X
authors.lastname: Zhou
authors.affiliation: College of Agronomy and Plant Protection, Qingdao Agricultural University, Changcheng Road No. 700, Chengyang District, Qingdao 266000, PR China.
authors.forename: Shengqi
authors.initials: S
authors.lastname: Chi
authors.affiliation: Istituto per la Protezione Sostenibile delle Piante CNR, UO Bari, Via Amendola, 70126 Bari, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Di Serio
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Yuanmingyuan West Road No. 2, Haidian District, Beijing 100193, PR China.
authors.forename: Shifang
authors.initials: S
authors.lastname: Li
mesh_terms: D017791:Geminiviridae / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D016679:Genome, Viral; D008969:Molecular Sequence Data; D031625:Morus / Q000821:virology*; D016366:Open Reading Frames; D010802:Phylogeny; D010935:Plant Diseases / Q000821:virology*; D014764:Viral Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D014764:Viral Proteins