Phylogeny of Banana Streak Virus Reveals Recent and Repetitive Endogenization in the Genome of Its Banana Host (Musa sp.)
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Banana streak virus (BSV) is a plant dsDNA pararetrovirus (family Caulimoviridae, genus badnavirus). Although integration is not an essential step in the BSV replication cycle, the nuclear genome of banana (Musa sp.) contains BSV endogenous pararetrovirus sequences (BSV EPRVs). Some BSV EPRVs are infectious by reconstituting a functional viral genome. Recent studies revealed a large molecular diversity of episomal BSV viruses (i.e., nonintegrated) while others focused on BSV EPRV sequences only. In this study, the evolutionary history of badnavirus integration in banana was inferred from phylogenetic relationships between BSV and BSV EPRVs. The relative evolution rates and selective pressures (dN/dS ratio) were also compared between endogenous and episomal viral sequences. At least 27 recent independent integration events occurred after the divergence of three banana species, indicating that viral integration is a recent and frequent phenomenon. Relaxation of selective pressure on badnaviral sequences that experienced neutral evolution after integration in the plant genome was recorded. Additionally, a significant decrease (35%) in the EPRV evolution rate was observed compared to BSV, reflecting the difference in the evolution rate between episomal dsDNA viruses and plant genome. The comparison of our results with the evolution rate of the Musa genome and other reverse-transcribing viruses suggests that EPRVs play an active role in episomal BSV diversity and evolution.
KeywordsBadnavirus Banana (Musa sp.) Banana streak virus (BSV) dN/dS ratio Endogenous pararetrovirus (EPRV) Evolution rate Integration Selective constraints
We are grateful to Nathalie Laboureau and Serge Galzi for technical assistance. We thank the members of our team, Elisabeth Fournier, Eric Bazin, and Nicolas Galtier for their helpful comments, and Philippe Rott for improving the manuscript. P.G. was supported by a PhD grant CIRAD – Région Languedoc Roussillon.
- Ben-Dov Y (1994) A systematic catalogue of the mealybugs of the world (Insecta: Homoptera: Coccoidea: Pseudococcidae and Putoidae) with data on geographical distribution, host plants, biology and economic importance. Intercept Publications, Andover, p 686Google Scholar
- Fauquet CM, Mayo MA, Maniloff J, Desselberger U, Ball LA (2005) Virus taxonomy, VIII report of the ICTV. Elsevier/Academic Press, LondonGoogle Scholar
- Flint SJ, Enquist LW, Skalka AM (2003) Principles of virology: molecular biology, pathogenesis, and control of animal viruses, 2nd edn. ASM Press, Washington, DCGoogle Scholar
- Hall TA (1999) BioEdit: a user-friendly biological sequence alignment editor and analysis program for Windows 95/98/NT. Nucleic Acids Symp Ser 41:95–98Google Scholar
- Hohn T, Richert-Poggeler KR, Harper G, Schwarzacher T, Teo CH, Techeney PY, Iskra-Caruana ML, Hull R (2008) Evolution of integrated plant viruses. In: Roosinck M (ed) Virus evolution. Springer, Heidelberg, chapter 4, pp 53–81Google Scholar
- Jones DR (2000) Diseases of banana, abacá, and enset. CABI, WallingfordGoogle Scholar
- Lescot M, Piffanelli P, Ciampi AY, Ruiz M, Blanc G, Leebens-Mack J, da Silva FR, Santos CM, D’Hont A, Garsmeur O, Vilarinhos AD, Kanamori H, Matsumoto T, Ronning CM, Cheung F, Haas BJ, Althoff R, Arbogast T, Hine E, Pappas GJ Jr, Sasaki T, Souza MT Jr, Miller RN, Glaszmann JC, Town CD (2008) Insights into the Musa genome: syntenic relationships to rice and between Musa species. BMC Genomics 9:58PubMedCrossRefGoogle Scholar
- Lockhart B, Jones D (2000) Banana streak. In: Jones DR (ed) Diseases of banana, abaca and enset. CABI, Wallingford, pp 263–274Google Scholar
- Noreen F, Akbergenov R, Hohn T, Richert-Poggeler KR (2007) Distinct expression of endogenous Petunia vein clearing virus and the DNA transposon dTph1 in two Petunia hybrida lines is correlated with differences in histone modification and siRNA production. Plant J 50:219–229PubMedCrossRefGoogle Scholar
- Swofford DL (2002) PAUP* 4: phylogenetic analysis using parsimony (and other methods). Sinauer, SunderlandGoogle Scholar
- Xia X (1999) DAMBE (software package for data analysis in molecular biology and evolution) user manual. Department of Ecology and Biodiversity, University of Hong Kong, Hong KongGoogle Scholar