Identification of a Sequence Element Involved in AC2-Mediated Transactivation of the Pepper Huasteco Virus Coat Protein Gene

The geminivirus AC2 gene product transactivates the expression of the coat and movement protein (CP and BV1) genes, and this effect seems to be mediated by specific although hitherto unknown cis-acting elements. In this work we examined regions from the CP and BV1 gene promoters of pepper huasteco virus (PHV) to define the sequence elements involved in regulation by AC2. Results from transient gene expression and transgenic plant assays suggest that a truncated 115-nt CP promoter is still responsive to the viral transactivator. This promoter contains three elements similar to a sequence motif termed conserved late element (CLE), which is found in the regulatory regions of many geminiviruses and that was previously suggested, on a theoretical basis, to be a potential functional target for AC2 (Argu¨ello-Astorga et al. (1994), Virology 203, 90–100). To confirm these results, an oligonucleotide containing two CLE motifs was synthesized and characterized in gain-of-function experiments. Transient expression assays showed that this 29-nt sequence is able to confer AC2 responsiveness to heterologous promoters. A smaller oligonucleotide (16 nt) containing a single CLE also conferred this activity. In addition, when the CLE motifs were mutated in their original context (truncated 115-nt promoter), this modified promoter lost its ability to be transactivated by AC2. All these results support the involvement, at least in the case of PHV, of CLE sequences in the process of transactivation.

• Autores: Monsalve Fonnegra, Zulma Isabel; Ruíz Medrano, Roberto; Guevara González, Ramón Gerardo; Argüello Astorga, Gerardo Rafael; Herrera Estrella, Luis Rafael; Rivera Bustamante, Rafael Francisco
• Tipo de recurso: Article of investigation
• Fecha de publicación: 1999
• Institución: Universidad de Antioquia
• Repositorio: Repositorio UdeA
• Idioma: eng
• OAI Identifier: oai:bibliotecadigital.udea.edu.co:10495/46136
• Acceso en línea: https://hdl.handle.net/10495/46136
• Palabra clave: Geminiviridae; Viral Regulatory and Accessory Proteins; Proteínas Reguladoras y Accesorias Virales; Plant Viruses; Virus de Plantas; Gene Expression Regulation, Viral; Regulación Viral de la Expresión Génica; DNA-Binding Proteins; Proteínas de unión al ADN; Capsid; Cápside; Genes, Viral; Genes virales; Plant Viral Movement Proteins; Proteínas de Movimiento Viral de Plantas; Viral Proteins; Proteínas Virales; Transcriptional Activation; Activación Transcripcional; https://id.nlm.nih.gov/mesh/D017791; https://id.nlm.nih.gov/mesh/D054334; https://id.nlm.nih.gov/mesh/D010942; https://id.nlm.nih.gov/mesh/D015967; http://id.nlm.nih.gov/mesh/D004268; http://id.nlm.nih.gov/mesh/D002213; http://id.nlm.nih.gov/mesh/D005814; http://id.nlm.nih.gov/mesh/D053830; http://id.nlm.nih.gov/mesh/D014764; http://id.nlm.nih.gov/mesh/D015533; ODS 15: Vida de ecosistemas terrestres. Proteger, restablecer y promover el uso sostenible de los ecosistemas terrestres, gestionar sosteniblemente los bosques, luchar contra la desertificación, detener e invertir la degradación de las tierras y detener la pérdida de biodiversidad
• Rights: openAccess
• License: http://creativecommons.org/licenses/by-nc-nd/4.0/