Dataset Information

Complete Genome Sequence Analysis of Two Divergent Groups of Sweet potato chlorotic fleck virus Isolates Collected from Korea.

ABSTRACT: The Sweet potato chlorotic fleck virus (SPCFV), of the genus Carlavirus (family Betaflexiviridae), was first detected as one of several viruses infecting sweet potatoes (Ipomea batatas L.) in Korea. Out of 154 sweet potato samples collected in 2012 that were showing virus-like symptoms, 47 (31%) were infected with SPCFV, along with other viruses. The complete genome sequences of four SPCFV isolates were determined and analyzed using previously reported genome sequences. The complete genomes were found to contain 9,104-9,108 nucleotides, excluding the poly-A tail, containing six putative open reading frames (ORFs). Further, the SPCFV Korean isolates were divided into two groups (Group I and Group II) by phylogenetic analysis based on the complete nucleotide sequences; Group I and Group II had low nucleotide sequence identities of about 73%. For the first time, we determined the complete genome sequence for the Group II SPCFV isolates. The amino acid sequence identity in coat proteins (CP) between the two groups was over 90%, whereas the amino acid sequence identity in other proteins was less than 80%. In addition, SPCFV Korean isolates had a low amino acid sequence identity (61% CPs and 47% in the nucleotide- binding protein [NaBp] region) to that of Melon yellowing-associated virus (MYaV), a typical Carlavirus.

SUBMITTER: Kwak HR

PROVIDER: S-EPMC6200045 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Complete Genome Sequence Analysis of Two Divergent Groups of Sweet potato chlorotic fleck virus Isolates Collected from Korea.

Kwak Hae-Ryun HR Kim Jaedeok J Kim Mikyeong M Seo Jang-Kyun JK Kim Jeong-Soo JS Choi Hong-Soo HS

The plant pathology journal 20181001 5

The Sweet potato chlorotic fleck virus (SPCFV), of the genus Carlavirus (family Betaflexiviridae), was first detected as one of several viruses infecting sweet potatoes (Ipomea batatas L.) in Korea. Out of 154 sweet potato samples collected in 2012 that were showing virus-like symptoms, 47 (31%) were infected with SPCFV, along with other viruses. The complete genome sequences of four SPCFV isolates were determined and analyzed using previously reported genome sequences. The ...[more]

PMID: 30369855

Similar Datasets

Project description:Viruses infecting wild flora may have a significant negative impact on nearby crops, and vice-versa. Only limited information is available on wild species able to host economically important viruses that infect sweetpotatoes (Ipomoea batatas). In this study, Sweet potato chlorotic fleck virus (SPCFV; Carlavirus, Betaflexiviridae) and Sweet potato chlorotic stunt virus (SPCSV; Crinivirus, Closteroviridae) were surveyed in wild plants of family Convolvulaceae (genera Astripomoea, Ipomoea, Hewittia and Lepistemon) in Uganda. Plants belonging to 26 wild species, including annuals, biannuals and perennials from four agro-ecological zones, were observed for virus-like symptoms in 2004 and 2007 and sampled for virus testing. SPCFV was detected in 84 (2.9%) of 2864 plants tested from 17 species. SPCSV was detected in 66 (5.4%) of the 1224 plants from 12 species sampled in 2007. Some SPCSV-infected plants were also infected with Sweet potato feathery mottle virus (SPFMV; Potyvirus, Potyviridae; 1.3%), Sweet potato mild mottle virus (SPMMV; Ipomovirus, Potyviridae; 0.5%) or both (0.4%), but none of these three viruses were detected in SPCFV-infected plants. Co-infection of SPFMV with SPMMV was detected in 1.2% of plants sampled. Virus-like symptoms were observed in 367 wild plants (12.8%), of which 42 plants (11.4%) were negative for the viruses tested. Almost all (92.4%) the 419 sweetpotato plants sampled from fields close to the tested wild plants displayed virus-like symptoms, and 87.1% were infected with one or more of the four viruses. Phylogenetic and evolutionary analyses of the 3'-proximal genomic region of SPCFV, including the silencing suppressor (NaBP)- and coat protein (CP)-coding regions implicated strong purifying selection on the CP and NaBP, and that the SPCFV strains from East Africa are distinguishable from those from other continents. However, the strains from wild species and sweetpotato were indistinguishable, suggesting reciprocal movement of SPCFV between wild and cultivated Convolvulaceae plants in the field.

Project description:BackgroundSweet potato chlorotic stunt virus (family Closteroviridae, genus Crinivirus) features a large bipartite, single-stranded, positive-sense RNA genome. To date, only three complete genomic sequences of SPCSV can be accessed through GenBank. SPCSV was first detected from China in 2011, only partial genomic sequences have been determined in the country. No report on the complete genomic sequence and genome structure of Chinese SPCSV isolates or the genetic relation between isolates from China and other countries is available.Methodology/principal findingsThe complete genomic sequences of five isolates from different areas in China were characterized. This study is the first to report the complete genome sequences of SPCSV from whitefly vectors. Genome structure analysis showed that isolates of WA and EA strains from China have the same coding protein as isolates Can181-9 and m2-47, respectively. Twenty cp genes and four RNA1 partial segments were sequenced and analyzed, and the nucleotide identities of complete genomic, cp, and RNA1 partial sequences were determined. Results indicated high conservation among strains and significant differences between WA and EA strains. Genetic analysis demonstrated that, except for isolates from Guangdong Province, SPCSVs from other areas belong to the WA strain. Genome organization analysis showed that the isolates in this study lack the p22 gene.Conclusions/significanceWe presented the complete genome sequences of SPCSV in China. Comparison of nucleotide identities and genome structures between these isolates and previously reported isolates showed slight differences. The nucleotide identities of different SPCSV isolates showed high conservation among strains and significant differences between strains. All nine isolates in this study lacked p22 gene. WA strains were more extensively distributed than EA strains in China. These data provide important insights into the molecular variation and genomic structure of SPCSV in China as well as genetic relationships among isolates from China and other countries.

Project description:BACKGROUND:The bipartite single-stranded RNA genome of Sweet potato chlorotic stunt virus (SPCSV, genus Crinivirus; Closteroviridae) encodes a Class 1 RNase III (RNase3), a putative hydrophobic protein (p7) and a 22-kDa protein (p22) from genes located in RNA1. RNase3 and p22 suppress RNA silencing, the basal antiviral defence mechanism in plants. RNase3 is sufficient to render sweetpotato (Ipomoea batatas) virus-susceptible and predisposes it to development of severe diseases following infection with unrelated virus. The incidence, strains and gene content of SPCSV infecting wild plant species have not been studied. METHODOLOGY/PRINCIPAL FINDINGS:Thirty SPCSV isolates were characterized from 10 wild Ipomoea species, Hewittia sublobata or Lepistemon owariensis (family Convolvulaceae) in Uganda and compared with 34 local SPCSV isolates infecting sweetpotatoes. All isolates belonged to the East African (EA) strain of SPCSV and contained RNase3 and p7, but p22 was not detected in six isolates. The three genes showed only limited genetic variability and the proteins were under purifying selection. SPCSV isolates lacking p22 synergized with Sweet potato feathery mottle virus (SPFMV, genus potyvirus; Potyviridae) and caused severe symptoms in co-infected sweetpotato plants. One SPCSV isolate enhanced accumulation of SPFMV, but no severe symptoms developed. A new whitefly-transmitted virus (KML33b) encoding an RNase3 homolog (<56% identity to SPCSV RNase3) able to suppresses sense-mediated RNA silencing was detected in I. sinensis. CONCLUSIONS/SIGNIFICANCE:SPCSV isolates infecting wild species and sweetpotato in Uganda were genetically undifferentiated, suggesting inter-species transmission of SPCSV. Most isolates in Uganda contained p22, unlike SPCSV isolates characterized from other countries and continents. Enhanced accumulation of SPFMV and increased disease severity were found to be uncoupled phenotypic outcomes of RNase3-mediated viral synergism in sweetpotato. A second virus encoding an RNase3-like RNA silencing suppressor was detected. Overall, results provided many novel and important insights into evolutionary biology of SPCSV.

Dataset Information

Complete Genome Sequence Analysis of Two Divergent Groups of Sweet potato chlorotic fleck virus Isolates Collected from Korea.

Publications

Complete Genome Sequence Analysis of Two Divergent Groups of <i>Sweet potato chlorotic fleck virus</i> Isolates Collected from Korea.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets