Análisis funcional de Snakin - 1 en plantas transgénicas de Solanum tuberosum

Snakin-1 (SN1)es un péptido antimicrobiano rico en cisteínas aislado a partir de Solanum tuberosum que fue clasificado como miembro de la familia Snakin/GASA. Con el objetivo de estudiar el rol de SN1 in planta, se realizó una caracterización detallada de líneas sobreexpresantes y silenciadas para este gen. Si bien la sobreexpresión de SN1 no resultó en diferencias morfológicas evidentes con respecto a las plantas sin transformar, las líneas silenciadas mostraron una altura reducida, hojas de una forma atípica y de menor tamaño, e importantes defectos en los procesos de floración y de tuberización. El área foliar de las mismas presentó una disminución del 50-60 por ciento como resultado de un menor número de células por hoja. Con el fin de identificar vías metabólicas y procesos fisiológicos afectados en las líneas transgénicas se analizaron los perfiles metabólicos y la composición de la pared celular de las hojas. Asimismo, se estudió la participación de SN1 en la homeostasis redox y en el balance hormonal. Finalmente se hicieron análisis de los perfiles transcripcionales de las líneas transgénicas con el fin de esclarecer el modo de acción de SN1. Los resultados obtenidos demuestran que el silenciamiento de SN1 afecta la división celular, el metabolismo primario y la composición de la pared celular lo cual resulta en notorias alteraciones fenotípicas e indica que este gen participa en el crecimiento y en el desarrollo además de su rol en defensa. Como fue descripto para otros genes de la familia Snakin/GASA, es posible que SN1 cumpla su rol mediante la modulación de las especies reactivas de oxígeno y de la síntesis de hormonas en la planta. Asimismo, la disponibilidad del genoma secuenciado de la papa nos permitió identificar 14 nuevos miembros de la familia Snakin/GASA que se suman a los tres genes previamente reportados para esta especie

Isolation and characterization of the tissue and development-specific potato snakin-1 promoter inducible by temperature and wounding

Snakin-1 (StSN1) is a broad-spectrum antimicrobial peptide isolated from Solanum tuberosum. Homologous proteins have been identified in a wide range of species but there is no apparent consensus in the roles they play. A 1394 bp fragment of the 5’upstream region of StSN1 gene, designated PStSN1, was isolated from the potato genome and sequenced. Bioinformatics analyses revealed a total of 55 potential regulatory motifs related to tissue-specificity, stress, defence and hormone responsiveness, among others. PStSN1 spatial and temporal activity was studied in transgenic Arabidopsis plants expressing a reporter gene under this promoter control (PStSN1::GUS). Histochemical staining revealed PStSN1::GUS expression in the root vasculature, cotyledons, young leaves and floral organs. Moreover, GUS staining was detected in young developmental stages gradually decreasing as the plant aged. Stress treatments on transgenic plants showed that PStSN1 activity was induced by high/low temperature and wounding. The characterization of PStSN1 in a model plant establishes a framework for the understanding of its possible biological functions and provides a potential tool for plant modification through genetic engineering.Instituto de BiotecnologíaFil: Almasia, Natalia Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Nahirñak, Vanesa. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Vazquez Rovere, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentin

State of the art of genetic engineering in potato: from the first report to its future potential

Potato (Solanum tuberosum L.) is a crop of world importance that produces tubers of high nutritional quality. It is considered one of the promising crops to overcome the challenges of poverty and hunger worldwide. However, it is exposed to different biotic and abiotic stresses that can cause significant losses in production. Thus, potato is a candidate of special relevance for improvements through conventional breeding and biotechnology. Since conventional breeding is time-consuming and challenging, genetic engineering provides the opportunity to introduce/switch-off genes of interest without altering the allelic combination that characterize successful commercial cultivars or to induce targeted sequence modifications by New Breeding Techniques. There is a variety of methods for potato improvement via genetic transformation. Most of them incorporate genes of interest into the nuclear genome; nevertheless, the development of plastid transformation protocols broadened the available approaches for potato breeding. Although all methods have their advantages and disadvantages, Agrobacterium-mediated transformation is the most used approach. Alternative methods such as particle bombardment, protoplast transfection with polyethylene glycol and microinjection are also effective. Independently of the DNA delivery approach, critical steps for a successful transformation are a rapid and efficient regeneration protocol and a selection system. Several critical factors affect the transformation efficiency: vector type, insert size, Agrobacterium strain, explant type, composition of the subculture media, selective agent, among others. Moreover, transient or stable transformation, constitutive or inducible promoters, antibiotic/herbicide resistance or marker-free strategies can be considered. Although great efforts have been made to optimize all the parameters, potato transformation protocols are highly genotype-dependent. Genome editing technologies provide promising tools in genetic engineering allowing precise modification of targeted sequences. Interestingly, transient expression of genome editing components in potato protoplasts was reported to generate edited plants without the integration of any foreign DNA, which is a valuable aspect from both a scientific and a regulatory perspective. In this review, current challenges and opportunities concerning potato genetic engineering strategies developed to date are discussed. We describe their critical parameters and constrains, and the potential application of the available tools for functional analyses or biotechnological purposes. Public concerns and safety issues are also addressed.Instituto de BiotecnologíaFil: Nahirñak, Vanesa. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Nahirñak, Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Almasia, Natalia Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Almasia, Natalia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: González, Matías Nicolás. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible (IPADS); ArgentinaFil: González, Matías Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Massa, Gabriela Alejandra. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible (IPADS); ArgentinaFil: Massa, Gabriela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Massa, Gabriela Alejandra. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Décima Oneto, Cecilia Andrea. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible (IPADS); ArgentinaFil: Décima Oneto, Cecilia Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Décima Oneto, Cecilia Andrea. Universidad Nacional de Mar del Plata. Facultad de Ciencias Agrarias; ArgentinaFil: Feingold, Sergio Enrique. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce. Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible (IPADS); ArgentinaFil: Feingold, Sergio Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Hopp, Horacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hopp, Horacio Esteban. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Vazquez Rovere, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Vazquez Rovere, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Snakin-1 affects reactive oxygen species and ascorbic acid levels and hormone balance in potato

Snakin-1 is a member of the Solanum tuberosum Snakin/GASA family. We previously demonstrated that Snakin-1 is involved in plant defense to pathogens as well as in plant growth and development, but its mechanism of action has not been completely elucidated yet. Here, we showed that leaves of Snakin-1 silenced potato transgenic plants exhibited increased levels of reactive oxygen species and significantly reduced content of ascorbic acid. Furthermore, Snakin-1 silencing enhanced salicylic acid content in accordance with an increased expression of SA-inducible PRs genes. Interestingly, gibberellic acid levels were also enhanced and transcriptome analysis revealed that a large number of genes related to sterol biosynthesis were downregulated in these silenced lines. Moreover, we demonstrated that Snakin-1 directly interacts with StDIM/DWF1, an enzyme involved in plant sterols biosynthesis. Additionally, the analysis of the expression pattern of PStSN1::GUS in potato showed that Snakin-1 is present mainly in young tissues associated with active growth and cell division zones. Our comprehensive analysis of Snakin-1 silenced lines demonstrated for the first time in potato that Snakin-1 plays a role in redox balance and participates in a complex crosstalk among different hormones.Instituto de BiotecnologíaFil: Nahirñak, Vanesa. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Rivarola, Maximo Lisandro. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Almasia, Natalia Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Barrios Barón, María Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Vile, Denis. Institute National de la Recherche Agronomique. Laboratoire d'écophysiologie des Plantes sous Stress Environnementaux; Francia; Université de Montpellier; FranciaFil: Paniego, Norma Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vazquez Rovere, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria (INTA).Labintex Europa; Franci

First complete genome sequence of potato leafroll virus from Argentina

In this study, we determined for the first time the complete genomic sequence of an Argentinian isolate of Potato leafroll virus (PLRV), the type species of the genus Polerovirus. The isolate sequenced came from a Solanum tuberosum plant that had been naturally infected with the virus. Isolate PLRV-AR had a nucleotide sequence identity between 94.4 and 97.3% with several known PLRV isolates worldwide.Inst. de BiotecnologíaFil: Barrios Baron, Maria Pilar. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Agrofoglio, Yamila Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Delfosse, Veronica Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad Nacional de San Martín; ArgentinaFil: Nahirñak, Vanesa. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Gonzalez De Urreta, Martin Salvador. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Almasia, Natalia Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Vazquez Rovere, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Sabio Y Garcia, Julia Verónica. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentin

Potato Snakin-1: an antimicrobial player of the trade-off between host defense and development

Snakin-1 (SN1) from potato is a cysteine-rich antimicrobial peptide with high evolutionary conservation. It has 63 amino acid residues, 12 of which are cysteines capable of forming six disulfide bonds. SN1 localizes in the plasma membrane, and it is present mainly in tissues associated with active growth and cell division. SN1 is active in vitro against bacteria, fungus, yeasts, and even animal/human pathogens. It was demonstrated that it also confers in vivo protection against commercially relevant pathogens in overexpressing potato, wheat, and lettuce plants. Although researchers have demonstrated SN1 can disrupt the membranes of E. coli, its integral antimicrobial mechanism remains unknown. It is likely that broad-spectrum antimicrobial activity is a combined outcome of membrane disruption and inhibition of intracellular functions. Besides, in potato, partial SN1 silencing affects cell division, leaf metabolism, and cell wall composition, thus revealing additional roles in growth and development. Its silencing also affects reactive oxygen species (ROS) and ROS scavenger levels. This finding indicates its participation in redox balance. Moreover, SN1 alters hormone levels, suggesting its involvement in the complex hormonal crosstalk. Altogether, SN1 has the potential to integrate development and defense signals directly and/or indirectly by modulating protein activity, modifying hormone balance and/or participating in redox regulation. Evidence supports a paramount role to SN1 in the mechanism underlying growth and immunity balance. Furthermore, SN1 may be a promising candidate in preservation, and pharmaceutical or agricultural biotechnology applications.Fil: Almasia, Natalia Ines. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación En Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Nahirñak, Vanesa. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación En Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación En Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Vazquez Rovere, Cecilia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación En Ciencias Veterinarias y Agronómicas. Instituto de Agrobiotecnología y Biología Molecular. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Agrobiotecnología y Biología Molecular; Argentin

Snakin/GASA proteins : involvement in hormone crosstalk and redox homeostasis

Snakin/GASA proteins are widely distributed among plant species. They are expressed in different plant organs with high tissue and temporal specificity, and their subcellular localization varies among the different members. Interestingly, all of them maintain 12 cysteines of the C-terminus in highly conserved positions of the aminoacid sequences that are essential for their biochemical activity and probably responsible for their protein structure. Despite their common features, their functions are not completely elucidated and little is known about their mode of action. This review focuses on the current knowledge about this intriguing family of peptides and advances comprising gene regulation analyses, expression pattern studies and phenotypic characterization of mutants and transgenic plants. Furthermore, we discuss the roles of Snakin/GASA proteins in several aspects of plant development, plant responses to biotic or abiotic stress and their participation in hormone crosstalk and redox homeostasis.Instituto de BiotecnologíaFil: Nahirñak, Vanesa. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Almasia, Natalia Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Vazquez Rovere, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina

Genome-wide Analysis of the Snakin/GASA Gene Family in Solanum tuberosum cv. Kennebec

Snakin/GASA proteins have been involved in different aspects of plant growth and development although their exact role is still intriguing. All of them maintain 12 cysteines of the C-terminus in highly conserved positions that are responsible for their structure and are essential for their biochemical activity as antioxidants. Two members were isolated from Solanum tuberosum to date (Snakin-1 and Snakin-2) and were shown to have antimicrobial activity. We have recently demonstrated that Snakin-1 has additional roles in plant growth and development. We carried out a genome-wide search for new Snakin/GASA family members in potato. 16 Snakin/GASA genes were isolated, sequenced and characterized. Interestingly, we found in Solanum tuberosum subsp. tuberosum cv. Kennebec that Snakin-1, Snakin-2 and Snakin-3 expression is affected by bacterial and/or fungal inoculation. These results strengthen the participation of Snakin-1 and Snakin-2 genes in biotic stress tolerance and suggest that Snakin-3 is also involved in plant defense. The data presented here could be a good starting point for more focused and deep investigations regarding the biological functions of potato Snakin/GASA genes during plant development and in response to environmental stress.Fil: Nahirñak, Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Rivarola, Maximo Lisandro. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: González de Urreta, Martín Salvador. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Paniego, Norma Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Hopp, Horacio Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Almasia, Natalia Ines. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Vazquez Rovere, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; Argentin

Potato Snakin-1 gene silencing affects cell division, primary metabolism, and cell wall composition

Snakin-1 (SN1) is an antimicrobial cysteine-rich peptide isolated from potato (Solanum tuberosum) that was classified as a member of the Snakin/Gibberellic Acid Stimulated in Arabidopsis protein family. In this work, a transgenic approach was used to study the role of SN1 in planta. Even when overexpressing SN1, potato lines did not show remarkable morphological differences from the wild type; SN1 silencing resulted in reduced height, which was accompanied by an overall reduction in leaf size and severe alterations of leaf shape. Analysis of the adaxial epidermis of mature leaves revealed that silenced lines had 70% to 90% increases in mean cell size with respect to wild-type leaves. Consequently, the number of epidermal cells was significantly reduced in these lines. Confocal microscopy analysis after agroinfiltration of Nicotiana benthamiana leaves showed that SN1-green fluorescent protein fusion protein was localized in plasma membrane, and bimolecular fluorescence complementation assays revealed that SN1 self-interacted in vivo. We further focused our study on leaf metabolism by applying a combination of gas chromatography coupled to mass spectrometry, Fourier transform infrared spectroscopy, and spectrophotometric techniques. These targeted analyses allowed a detailed examination of the changes occurring in 46 intermediate compounds from primary metabolic pathways and in seven cell wall constituents. We demonstrated that SN1 silencing affects cell division, leaf primary metabolism, and cell wall composition in potato plants, suggesting that SN1 has additional roles in growth and development beyond its previously assigned role in plant defense.Fil: Nahirñak, Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Almasia, Natalia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Fernández, Paula Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología, Biología Molecular y Celular. Laboratorio de Fisiología y Biología Molecular; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Estevez, Jose Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología, Biología Molecular y Celular. Laboratorio de Fisiología y Biología Molecular; ArgentinaFil: Carrari, Fernando Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Vazquez Rovere, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; Argentin

Argentinian potato leafroll virus P0 protein : Novel activities for a previously known suppressor

The potato leafroll virus (PLRV) P0 protein (P0PL) is a suppressor of RNA silencing. In this study, we showed that P0 protein from an Argentinian isolate of PLRV (P0PL‐Ar) has an additional activity not described for other PLRV or P0 proteins from poleroviruses. Besides reporting that P0PL‐Ar displays both local and systemic silencing suppressor activity, we demonstrated, for the first time, that P0PL‐Ar impedes accumulation of dsRNA‐derived siRNAs. We also showed that P0PL‐Ar interacts with Solanum tuberosum SKP1 orthologue (StSKP1) and triggers destabilization of ARGONAUTE 1 (AGO1) and that these actions are mediated by the F‐box‐like domain. A mutant in the GW/WG motif within the P0PL‐Ar F‐box‐like motif lost the suppression activity, the interaction with StSKP1 and abolished AGO1 decay. Interestingly, a mutant in the L76/P77 residues within the P0PL‐Ar F‐box‐like motif, which lost the suppression activity and the interaction with StSKP1, retained the capacity to enable AGO1 decay. Thus, unlike other P0 proteins of previously characterized poleroviruses, P0PL‐Ar seems to have a dual activity, according to the findings of this study. This protein would act at both an upstream and a downstream step of the RNA silencing pathway: upstream of Dicer‐like enzyme (DCL)‐mediated primary siRNA production and downstream at the RNA‐induced silencing complex (RISC) complex level. Our results contribute to the understanding of the different ways PLRV P0 proteins function as silencing suppressors.Instituto de BiotecnologíaFil: Barrios Baron, Maria Pilar. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Barrios Baron, Maria Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Delfosse, Veronica Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Delfosse, Veronica Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Delfosse, Veronica Cecilia. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; ArgentinaFil: Agrofoglio, Yamila Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Agrofoglio, Yamila Carla. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nahirñak, Vanesa. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Nahirñak, Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Almasia, Natalia Ines. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Almasia, Natalia Ines. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vazquez Rovere, Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Vazquez Rovere, Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Distefano, Ana Julia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Agrobiotecnología y Biología Molecular; ArgentinaFil: Distefano, Ana Julia. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Distefano, Ana Julia. Universidad Nacional de Luján (UNLU); Argentin