RT info:eu-repo/semantics/article T1 Two novel DNAs that enhance symptoms and overcome CMD2 resistance to cassava mosaic disease A1 León Guerra, Leandro Jesús A1 Ndunguru, Joseph A1 D. Doyle, Catherine A1 Sseruwagi, Peter A1 Plata, Germán A1 Legg, James P. A1 Thompson, Graham A1 Tohme, Joe A1 Aveling, Theresa A1 Ascencio-Ibáñez, José T. A1 Hanley-Bowdoin, Linda A2 BioquímicaMicrobiología, Biología Celular y Genética AB Cassava mosaic begomoviruses (CMBs)causecassavamosaicdisease (CMD)acrossAfricaandtheIndiansubcontinent. Like all membersofthegeminivirusfamily, CMBshavesmall,circular single-stranded DNA genomes. Wereportherethediscovery of twonovelDNAsequences,designatedSEGS-1andSEGS-2(forsequencesenhancinggeminivirussymptoms),thatenhance symptomsandbreakresistance toCMD.TheSEGSarecharacterizedbyGC-richregionsandtheabsenceoflongopenreading frames. Both SEGS enhanced CMDsymptomsincassava(Manihot esculenta Crantz) when coinoculated with African cassava mosaic virus (ACMV), East African cassava mosaic Cameroon virus (EACMCV), or East African cassava mosaic virus-Uganda (EACMV-UG).SEGS-1alsoovercameresistanceofacassavalandracecarrying the CMD2resistancelocus whencoinoculated with EACMV-UG.EpisomalformsofbothSEGSweredetectedinCMB-infectedcassavabutnotinhealthycassava.SEGS-2episomeswerealsofoundinvirions andwhiteflies. SEGS-1 hasnohomologytogeminivirusesortheirassociated satellites, but the cassava genomecontains a sequence that is 99%identical to full-length SEGS-1. The cassava genome also includes three sequences with 84to89%identitytoSEGS-2thattogetherencompassallofSEGS-2exceptfora52-bpregion,whichincludesthe episomal junction and a 26-bpsequencerelated to alphasatellite replication origins. These results suggest that SEGS-1 is derived fromthecassava genomeandfacilitates CMBinfection as an integrated copy and/or an episome, while SEGS-2 wasoriginally fromthecassava genomebutnowisencapsidatedintovirions andtransmitted as anepisomebywhiteflies. YR 2016 FD 2016 LK http://riull.ull.es/xmlui/handle/915/35868 UL http://riull.ull.es/xmlui/handle/915/35868 LA en NO DOI: 10.1128/JVI.02834-15 DS Repositorio institucional de la Universidad de La Laguna RD 01-nov-2024