Characterization of Cestrum yellow leaf curling virus: a new member of the family Caulimoviridae

Abstract

Cestrum yellow leaf curling virus (CmYLCV) has been characterized as the aetiological agent of the Cestrum parqui mosaic disease. The virus genome was cloned and the clone was proven to be infectious to C. parqui. The presence of typical viroplasms in virus-infected plant tissue and the information obtained from the complete genomic sequence confirmed CmYLCV as a member of the Caulimoviridae family. All characteristic domains conserved in plant pararetroviruses were found in CmYLCV. Its genome is 8253 bp long and contains seven open reading frames (ORFs). Phylogenetic analysis of the relationships with other members of the Caulimoviridae revealed that CmYLCV is closely related to the Soybean chlorotic mottle virus (SbCMV)-like genus and particularly to SbCMV. However, in contrast to the other members of this genus, the primer-binding site is located in the intercistronic region following ORF Ib rather than within this ORF, and an ORF corresponding to ORF VII is missing.

Cestrum yellow leaf curling virus (CmYLCV) promoter: a new strong constitutive promoter for heterologous gene expression in a wide variety of crops

“…This feature indicates that, in addition to being useful to direct high levels of gene expression in most cell and tissue types of a wide selection of crop plants, the CmYLCV promoter may also be useful for driving expression of a selectable marker gene for transgenic plant production. Importantly, our results show that the high expression levels are heritable, do not appear to be negatively influenced by multiple copies of the promoter and, because the virus has a narrow host range (Stavolone et al, 2003) and the promoter has low sequence similarity to other pararetroviruses, including, most notably, the CaMV 35S promoter, gene silencing is predicted to be unlikely. Thus, the CmYLCV promoter is a new and truly useful tool for agricultural research and biotechnology applications.…”

“…The 8253 bp double-stranded DNA genome of CmYLCV has been cloned and sequenced (Stavolone et al, 2003). Analysis of the CmYLCV genomic sequence revealed the presence of an AT-rich region within the 671 bp intergenic region containing a putative TATA box sequence (TATAAATA) (6395-6402) 5 of the translation start site of ORF1, which begins at 6756 of the genomic sequence ( Figure 1).…”

“…This was observed for CaMV, which is infectious to members of the Solanaceae, Resedaceae and most Cruciferae plant families. Of a wide range of test plants and commercially important crop species evaluated by mechanical inoculation, CmYLCV infected only C. parqui, C. elegans and Nicotiana clevelandii (Stavolone et al, 2003). This suggests that a crop plant transformed with the CmYLCV promoter has a high Figure 4.…”

Promoter diversity in multigene transformation

“…Because the CaMV 35S promoter has proven so successful, related caulimoviruses have been the first port of call. Examples include promoters from Figwort mosaic caulimovirus (FMV; Bhattacharyya et al 2002), Cassava vein mosaic virus (CsVMV; Verdaguer et al 1996), Cestrum yellow leaf curling virus (CmYLCV; Stavolone et al 2003), Mirabilis mosaic virus (MiMV; Dey and Maiti 1999) and Peanut chlorotic streak virus (PClSV; Maiti and Shepherd 1998;Bhattacharyya et al 2003). The CmYLCV promoter sequence is available from Syngenta Biotechnology, Inc. for limited research purposes, and has been used to express glyoxalase I (gly I) to achieve salt tolerance in tobacco (Veena et al 1999) and mung bean (Bhomkar et al 2008).…”

Optimizing the Yield of Recombinant Pharmaceutical Proteins in Plants

“…The CaMV 35S promoter is more active in dicotyledonous plants than in cereals, and indeed the same promoter can vary in efficiency in different host species even if those species are closely related [18]. A number of comparable virus-derived promoters have been developed, such as the Cestrum yellow leaf curling virus (CmYLCV) promoter developed by Syngenta AG [19]. However, molecular farming in cereals has benefited from the use of endogenous promoters from housekeeping genes as well as promoters from viruses that infect cereal species.…”