1887

Abstract

Complete DNA-A sequences of nine Pakistani geminivirus isolates from leaf curl-affected cotton (CLCuV-PK) or from okra, and the partial sequences of several additional isolates were determined. Sequences of isolates from cotton were of four types. Isolates from leaf curl-affected okra had virtually the same sequences as those from cotton. Isolates from yellow vein mosaic-affected okra were of two types (OYVMV types 201 and 301), both distinct from but closely related to the virus isolates from cotton. Of these six types, two types of CLCuV- PK are the most closely related but another (CLCuV- PK type 72b) is the most distinct. Of the encoded proteins, coat protein (CP) is the most strongly conserved (92–100%aminoacid sequence identity), and AC4 protein the most variable (41–87%).

The 5′ and 3′ halves of the intergenic region of some isolates had different affinities and occurred in seven combinations, suggesting that recombination had occurred and that the origin of replication was a favoured recombination site. Similarly, the first 1520 nt of CLCuV-PK type 804a DNA resembled those of OYVMV type 301 DNA but the remaining 1224 nt were very different. The () gene and 5′ part of the intergenic region of CLCuV-PK type 72b closely resembled those of OYVMV type 301, whereas the rest of the sequence did not. The cotton leaf curl epidemic in Pakistan is caused by several distinct variants, with recombination events involving OYVMV and other unspecified gemini- viruses having probably been involved in their evolution.

Loading

Article metrics loading...

/content/journal/jgv/10.1099/0022-1317-79-4-915
1998-04-01
2022-05-21
Loading full text...

Full text loading...

/deliver/fulltext/jgv/79/4/9568988.html?itemId=/content/journal/jgv/10.1099/0022-1317-79-4-915&mimeType=html&fmt=ahah

References

  1. Accotto G. P., Mullineaux P. M., Brown S. C., Marie D. 1993; Digitaria streak geminivirus replicative forms are abundant in S-phase nuclei of infected cells. Virology 195:257–259
    [Google Scholar]
  2. Ali M., Ahmad Z., Tanveer M., Mahmood T. 1995; Cotton Leaf Curl Virus in the Punjab. Current Situation and Review of Work. Multan: Central Cotton Research Institute/Ministry of Food, Agriculture and Livestock, Government of Pakistan/Asian Development Bank;
    [Google Scholar]
  3. Anon 1994; Program Manual for the Wisconsin Package. Version 8 Madison: Genetics Computer Group;
  4. Arguello-Astorga G., Herrera-Estrella L., Rivera-Bustamente R. 1994; Experimental and theoretical definition of geminivirus origin of replication. Plant Molecular Biology 26:553–556
    [Google Scholar]
  5. Briddon R. W., Pinner M. S., Stanley J., Markham P. G. 1990; Geminivirus coat protein gene replacement alters insect specificity. Virology 177:85–94
    [Google Scholar]
  6. Hameed S., Ehsan-ul-Haq Khalid S., Hashmi A. A. 1994; Cotton leaf curl disease in Pakistan caused by a whitefly-transmitted geminivirus. Plant Disease 78:529
    [Google Scholar]
  7. Harrison B. D., Liu Y. L., Khalid S., Hameed S., Otim-Nape G. W., Robinson D. J. 1997; Detection and relationships of cotton leaf curl virus and allied whitefly-transmitted geminiviruses occurring in Pakistan. Annals of Applied Biology 130:61–75
    [Google Scholar]
  8. Hong Y. G., Harrison B. D. 1995; Nucleotide sequences from tomato leaf curl viruses from different countries: evidence for three geographically separate branches in evolution of the coat protein of whitefly-transmitted geminiviruses. Journal of General Virology 76:2043–2049
    [Google Scholar]
  9. Hong Y. G., Robinson D. J., Harrison B. D. 1993; Nucleotide sequence evidence for the occurrence of three distinct whitefly- transmitted geminiviruses in cassava. Journal of General Virology 74:2437–2443
    [Google Scholar]
  10. Laufs J., Traut W., Heyraud F., Matzeit V., Rogers S. G., Schell J., Gronenborn B. 1995; In vitro cleavage and joining at the viral origin of replication by the replication initiator protein of tomato yellow leaf curl virus. Proceedings of the National Academy of Sciences, USA 92:3879–3883
    [Google Scholar]
  11. McGrath P. F., Harrison B. D. 1995; Transmission of tomato leaf curl geminiviruses by Bemisia tabaci : effects of virus isolate and vector biotype. Annals of Applied Biology 126:307–316
    [Google Scholar]
  12. Mansoor S., Bedford I., Pinner M. S., Stanley J., Markham P. G. 1993; A whitefly-transmitted geminivirus associated with cotton leaf curl disease in Pakistan. Pakistan Journal of Botany 25:105–107
    [Google Scholar]
  13. Michel B., Ehrlich S. D. 1986; Illegitimate recombination at the replication origin of bacteriophage M13. Proceedings of the National Academy of Sciences, USA 83:3386–3390
    [Google Scholar]
  14. Nadeem A. 1995 Molecular characterization of two cotton geminiviruses PhD Dissertation University of Arizona, USA:
    [Google Scholar]
  15. Nagar S., Pedersen T. J., Carrick K. M., Hanley-Bowdoin L., Robertson D. 1995; A geminivirus induces expression of a host DNA synthesis protein in terminally differentiated plant cells. Plant Cell 7:705–719
    [Google Scholar]
  16. Orozco B. M., Miller A. B., Settlage S. B., Hanley-Bowdoin L. 1997; Functional domains of a geminivirus replication protein. Journal of Biological Chemistry 272:9840–9846
    [Google Scholar]
  17. Padidam M., Beachy R. N., Fauquet C. 1995; Tomato leaf curl geminivirus in India has a bipartite genome and coat protein is not essential for infectivity. Journal of General Virology 76:25–35
    [Google Scholar]
  18. Stanley J. 1995; Analysis of African cassava mosaic virus recombinants suggests strand nicking occurs within the conserved nona-nucleotide motif during the initiation of rolling circle DNA replication. Virology 206:707–712
    [Google Scholar]
  19. Zhou X., Liu Y., Calvert L., Munoz C., Otim-Nape G. W., Robinson D. J., Harrison B. D. 1997; Evidence that DNA-A of a geminivirus associated with severe cassava mosaic disease in Uganda has arisen by interspecific recombination. Journal of General Virology 78:2101–2111
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/jgv/10.1099/0022-1317-79-4-915
Loading
/content/journal/jgv/10.1099/0022-1317-79-4-915
Loading

Data & Media loading...

Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error