RESUMEN
Fragaria chiloensis is a strawberry endemic from Chile with attractive white-pink fruit, pleasant aroma and taste. However, this fruit has a limited post-harvest period due to fast softening. Several transcription factors (TFs) are involved in the regulation of fruit ripening, and members of the NAC family have been implicated in cell wall remodeling. FcNAC1 was isolated from F. chiloensis fruit, coding a protein of 332 amino acid residues and displaying a characteristic NAC domain at the N terminus. FcNAC1 protein showed nuclear localization. An increase in transcript level was observed during ripening. A sequence of 1488 bp of FcNAC1 promoter was obtained. In silico analysis identified cis elements able to respond to some hormones and Secondary wall NAC binding elements (SNBE), and responding to auxin and ABA. A structural model of FcNAC1 provided evidence for interaction with DNA sequences containing SNBE, while a dual luciferase assay confirmed the transcriptional activation by FcNAC1 of the promoter of FcPL, a gene involved in cell wall remodeling in F. chiloensis fruit. The results suggest the participation of FcNAC1 during ripening development of strawberry fruit, by regulating pectin metabolism during softening.
Asunto(s)
Proteínas de Unión al ADN/metabolismo , Fragaria/fisiología , Proteínas de Plantas/metabolismo , Factores de Transcripción/metabolismo , Ácido Abscísico/metabolismo , Pared Celular/metabolismo , Chile , Clonación Molecular , ADN de Plantas/química , ADN de Plantas/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/aislamiento & purificación , Frutas/citología , Frutas/metabolismo , Regulación de la Expresión Génica de las Plantas/fisiología , Ácidos Indolacéticos/metabolismo , Simulación de Dinámica Molecular , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/aislamiento & purificación , Regiones Promotoras Genéticas/genética , Dominios y Motivos de Interacción de Proteínas , Factores de Transcripción/química , Factores de Transcripción/genética , Factores de Transcripción/aislamiento & purificaciónRESUMEN
The identification and characterization of differential gene expression from tissues subjected to stress has gained much attention in plant research. The recognition of elements involved in the response to a particular stress enhances the possibility of promoting crop improvement through direct genetic modification. However, the performance of some of the 'first generation' of transgenic plants with the incorporation of a single gene has not always been as expected. These results have stimulated the development of new transgenic constructions introducing more than one gene and capable of modifying complex pathways. Several techniques are available to conduct the analysis of gene regulation, with such information providing the basis for novel constructs specifically designed to modify metabolism. This review deals with techniques that allow the identification and characterization of differentially-expressed genes and the use of molecular pathway information to produce transgenic plants.