RT info:eu-repo/semantics/article
T1 A new type of satellite associated with Cassava mosaic begomoviruses.
A1 León Guerra, Leandro Jesús de
A1 Aimone, Catherine D.
A1 Dallas, Mary M.
A1 Ndunguru, Joseph
A1 Ascencio Ibáñez, José T.
A1 Hanley Bowdoin, Linda
A2 BioquímicaMicrobiología, Biología Celular y Genética
K1 Arabidopsis
K1 begomovirus
K1 cassava mosaic disease
K1 SEGS
AB Cassava mosaic disease (CMD), which is caused by single-stranded DNA begomoviruses, severely limits cassava production across Africa. A previous study showed that CMD symptom severity and viral DNA accumulation increase in cassava in the presence of a DNA sequence designated SEGS-2 (sequence enhancing geminivirus symptoms). We report here that when SEGS-2 is coinoculated with African cassava mosaic virus (ACMV) onto Arabidopsis thaliana, viral symptoms increase. Transgenic Arabidopsis with an integrated copy of SEGS-2 inoculated with ACMV also display increased symptom severity and viral DNA levels. Moreover, SEGS-2 enables Cabbage leaf curl virus (CaLCuV) to infect a geminivirus-resistant Arabidopsis thaliana accession. Although SEGS-2 is related to cassava genomic sequences, an earlier study showed that it occurs as episomes and is packaged into virions in CMD-infected cassava and viruliferous whiteflies. We identified SEGS-2 episomes in SEGS-2 transgenic Arabidopsis. The episomes occur as both double-stranded and single-stranded DNA, with the single-stranded form packaged into virions. In addition, SEGS-2 episomes replicate in tobacco protoplasts in the presence, but not the absence, of ACMV DNA-A. SEGS-2 episomes contain a SEGS-2 derived promoter and an open reading frame with the potential to encode a 75-amino acid protein. An ATG mutation at the beginning of the SEGS-2 coding region does not enhance ACMV infection in A. thaliana. Together, the results established that SEGS-2 is a new type of begomovirus satellite that enhances viral disease through the action of an SEGS-2-encoded protein that may also be encoded by the cassava genome.
YR 2021
FD 2021
LK http://riull.ull.es/xmlui/handle/915/40735
UL http://riull.ull.es/xmlui/handle/915/40735
LA en
DS Repositorio institucional de la Universidad de La Laguna
RD 27-abr-2025