The receptor-like kinase ERECTA contributes to the shade-avoidance syndrome in a background-dependent manner

Background and Aims Plants growing at high densities perceive a decrease in the red to far-red (R/FR) ratio of incoming light. These changes in light quality trigger a suite of responses collectively known as the shade-avoidance syndrome (SAS) including hypocotyl and stem elongation, inhibition of branching and acceleration of flowering. Methods Quantitative trait loci (QTLs) were mapped for hypocotyl length to end-of-day far-red (EOD), a simulated shade-avoidance response, in recombinant inbred line (RIL) populations of Arabidopsis thaliana seedlings, derived from Landsberg erecta (Ler) and three accessions (Columbia, Col; Nossen, No-0; and Cape Verde Islands, Cvi-0). Key Results Five loci were identified as being responsible for the EOD response, with a positive contribution of Ler alleles on the phenotype independently of the RIL population. Quantitative complementation analysis and transgenic lines showed that PHYB is the candidate gene for EODRATIO5 in the Ler × Cvi-0 RIL population, but not for two co-localized QTLs, EODRATIO1 and EODRATIO2 mapped in the Ler × No-0 and Ler × Col RIL populations, respectively. The ERECTA gene was also implicated in the SAS in a background-dependent manner. For hypocotyl length EOD response, a positive contribution of erecta alleles was found in Col and Van-0, but not in Ler, Cvi-0, Hir-1 or Ws. Furthermore, pleiotropic effects of ERECTA in the EOD response were also detected for petiole and lamina elongation, hyponastic growth, and flowering time. Conclusions The results show that the analysis of multiple mapping populations leads to a better understanding of the SAS genetic architecture. Moreover, the background- and trait-dependent contribution of ERECTA in the SAS suggest that its function in shaded natural environments may be relevant for some populations in different phases of plant development. It is proposed that ERECTA is involved in canalization processes buffering the genetic variation of the SAS against environmental light fluctuations.Fil: Kasulin, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas A la Agricultura; ArgentinaFil: Agrofoglio, Yamila Carla. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas A la Agricultura; ArgentinaFil: Botto, Javier Francisco. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas A la Agricultura; Argentin

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

Nuevo método para la evaluación del comportamiento sanitario de variedades de algodón frente a enfermedad azul

Tradicionalmente, en los programas de mejoramiento del cultivo de algodón, la selección de variedades con resistencia genética a la enfermedad azul se realiza mediante la infección de las plantas con insectos vectores virulíferos que fueron criados en el laboratorio y que adquirieron el virus de plantas infectadas. Este método es complejo porque requiere de mucho tiempo para mantener la población de áfidos viable durante todo el año, instalaciones especiales para evitar el escape de los insectos y a su vez la cantidad de vectores disponible limita el número de material a evaluar. Otra estrategia para la evaluación del material es la siembra bajo condiciones de infección natural a campo. Estas determinaciones son muy dependientes de las infestaciones naturales de áfidos, las cuales no presentan una distribución uniforme en el campo. Esta variabilidad puede alterar el resultado y otorgar características resistentes a plantas susceptibles que no han sido infectadas. Por otro parte, la incidencia de la infección, dependiente de la presencia del áfido, es variable en cada campaña. Más aún, la sincronización entre la presencia de los vectores y el estadio de desarrollo de la planta es indispensable para la identificación de genotipos resistentes.La técnica de infección desarrollada representa una herramienta biotecnológica muy importante y podrá utilizarse como sistema de infección de rutina en los programas de mejoramiento de algodón siendo un método más sencillo y económico que el sistema de pulgones infectivos. El clon infectivo permitirá acelerar la selección de posibles genes de resistencia y/o tolerancia al CLRDV en el germoplasma de algodón, que puedan ser utilizados en mejoramiento e introgresión en variedades élite. Además, permitirá realizar distintos tipos de estudios para avanzar en el conocimiento del patosistema algodón-virus-vector. En este sentido, se demostró que la agroinfiltración del clon infectivo en plantas modelos como Arabidopsis thaliana y Nicotiana benthamiana permite establecer la infección en ellas. Si bien no son plantas de interés agronómico, ni huéspedes naturales del virus, ambas representan grandes herramientas para el estudio y caracterización de la interacción entre la planta y el virus. Entre las ventajas de poder trabajar con estas especies se encuentra el hecho de que cuentan con la totalidad de sus genomas secuenciados, ensamblados y ampliamente estudiados. Además, existe una amplia variedad de conocimientos obtenidos a partir de estudios realizados con ellas. Es por ello que la utilización del clon infectivo en plantas modelo permitirá explotar estas ventajas en pos de poder dilucidar las funciones virales del CLRDV. Un ejemplo de ello es el trabajo realizado en Nicotiana benthamiana para la caracterización funcional de la proteína P0 del CLRDV como supresor del mecanismo de silenciamiento posttranscripcional del hospedante, uno de los mecanismos de defensa contra patógenos que poseen las plantas.Fil: Delfosse, Verónica 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; ArgentinaFil: Agrofoglio, Yamila Carla. 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: Casse, María F.. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Chaco-formosa; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Bonacic Kresic, Iván. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Chaco-formosa; ArgentinaFil: Distéfano, Ana Julia. 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

Identification of a new cotton disease caused by an atypical cotton leafroll dwarf virus in Argentina

An outbreak of a new disease occurred in cotton (Gossypium hirsutum) fields in northwest Argentina starting in the 2009–10 growing season and is still spreading steadily. The characteristic symptoms of the disease included slight leaf rolling and a bushy phenotype in the upper part of the plant. In this study, we determined the complete nucleotide sequences of two independent virus genomes isolated from cotton blue disease (CBD)-resistant and -susceptible cotton varieties. This virus genome comprised 5,866 nucleotides with an organization similar to that of the genus Polerovirus and was closely related to cotton leafroll dwarf virus, with protein identity ranging from 88 to 98%. The virus was subsequently transmitted to a CBD-resistant cotton variety using Aphis gossypii and symptoms were successfully reproduced. To study the persistence of the virus, we analyzed symptomatic plants from CBD-resistant varieties from different cotton-growing fields between 2013 and 2015 and showed the presence of the same virus strain. In addition, a constructed full-length infectious cDNA clone from the virus caused disease symptoms in systemic leaves of CBD-resistant cotton plants. Altogether, the new leafroll disease in CBD-resistant cotton plants is caused by an atypical cotton leafroll dwarf virus.Inst. de BiotecnologíaFil: Agrofoglio, Yamila Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Delfosse, Veronica Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; ArgentinaFil: Casse, Maria Florencia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología y Biología Molecular y Celular; ArgentinaFil: Bonacic Kresic, Iván. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Distefano, Ana Julia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Fisiología y Biología Molecular y Celular; Argentin

The P0 protein encoded by cotton leafroll dwarf virus (CLRDV) inhibits local but not systemic RNA silencing

Plants employ RNA silencing as a natural defense mechanism against viruses. As a counter-defense, viruses encode silencing suppressor proteins (SSPs) that suppress RNA silencing. Most, but not all, the P0 proteins encoded by poleroviruses have been identified as SSP. In this study, we demonstrated that cotton leafroll dwarf virus (CLRDV, genus Polerovirus) P0 protein suppressed local silencing that was induced by sense or inverted repeat transgenes in Agrobacterium co-infiltration assay in Nicotiana benthamiana plants. A CLRDV full-length infectious cDNA clone that is able to infect N. benthamiana through Agrobacterium-mediated inoculation also inhibited local silencing in co-infiltration assays, suggesting that the P0 protein exhibits similar RNA silencing suppression activity when expressed from the full-length viral genome. On the other hand, the P0 protein did not efficiently inhibit the spread of systemic silencing signals. Moreover, Northern blotting indicated that the P0 protein inhibits the generation of secondary but not primary small interfering RNAs. The study of CLRDV P0 suppression activity may contribute to understanding the molecular mechanisms involved in the induction of cotton blue disease by CLRDV infection.Instituto de BiotecnologíaFil: Delfosse, Veronica Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Agrofoglio, Yamila Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Casse, Maria Florencia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Bonacic Kresic, Iván. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Ziegler-Graff, Véronique. Institut de Biologie Moléculaire des Plantes, laboratoire propre du CNRS conventionné avec l’Université de Strasbourg; FranciaFil: Distefano, Ana Julia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; 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

Agroinoculation of a full-length cDNA clone of cotton leafroll dwarf virus (CLRDV) results in systemic infection in cotton and the model plant Nicotiana benthamiana

Cotton blue disease is the most important viral disease of cotton in the southern part of South America. Its etiological agent, cotton leafroll dwarf virus (CLRDV), is specifically transmitted to host plants by the aphid vector (Aphis gossypii) and any attempt to perform mechanical inoculations of this virus into its host has failed. This limitation has held back the study of this virus and the disease it causes. In this study, a full-length cDNA of CLRDV was constructed and expressed in vivo under the control of cauliflower mosaic virus 35S promoter. An agrobacterium-mediated inoculation system for the cloned cDNA construct of CLRDV was developed. Northern and immunoblot analyses showed that after several weeks the replicon of CLRDV delivered by Agrobacterium tumefaciens in Gossypium hirsutum plants gave rise to a systemic infection and typical blue disease symptoms correlated to the presence of viral RNA and P3 capsid protein. We also demonstrated that the virus that accumulated in the agroinfected plants was transmissible by the vector A. gossypii. This result confirms the production of biologically active transmissible virions. In addition, the clone was infectious in Nicotiana benthamiana plants which developed interveinal chlorosis three weeks postinoculation and CLRDV was detected both in the inoculated and systemic leaves. Attempts to agroinfect Arabidopsis thaliana plants were irregularly successful. Although no symptoms were observed, the P3 capsid protein as well as the genomic and subgenomic RNAs were irregularly detected in systemic leaves of some agroinfiltrated plants. The inefficient infection rate infers that A. thaliana is a poor host for CLRDV. This is the first report on the construction of a biologically-active infectious full-length clone of a cotton RNA virus showing successful agroinfection of host and non-host plants. The system herein developed will be useful to study CLRDV viral functions and plant–virus interactions using a reverse genetic approach.Instituto de BiotecnologíaFil: Delfosse, Veronica Cecilia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Casse, Maria Florencia. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Agrofoglio, Yamila Carla. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; ArgentinaFil: Bonacic Kresic, Iván. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Sáenz Peña; ArgentinaFil: Hopp, Horacio Esteban. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; ArgentinaFil: Ziegler-Graff, Véronique. Institut de Biologie Moléculaire des Plantes, laboratoire propre du CNRS conventionné avec l’Université de Strasbourg; FranciaFil: Distefano, Ana Julia. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Biotecnología; Argentin

First Report of Potato Virus Y in Ornamental Calibrachoa in Argentina

Calibrachoa is a genus of the Solanaceae family endemic to South America that is used as an ornamental plant. Calibrachoa grows vigorously and has flowers of different colors such as pink, violet, red, yellow, and salmon (Milicia et al. 2016). Even though Calibrachoa hybrida in Argentina is mainly sold in the local markets and in a small percentage, the importance of this genus lies in being the main source of germplasm for ornamental varieties of great international impact. Viral diseases represent a serious problem for calibrachoa production because they decrease its commercial value and productivity. To date, only calibrachoa mottle virus (genus Carmovirus) and tobacco mild green mosaic virus (genus Tobamovirus) have been described to infect calibrachoa plants (Liu et al. 2003). The genus Potyvirus is one of the largest and most widespread important genera of plant viruses. Potato virus Y (PVY), the type species of the genus, is a major pathogen of solanaceous crops (potato, tobacco, pepper, and tomato), ornamentals (dahlia and petunia), and weeds (Karasev and Gray 2013; Quenouille et al. 2013). In 2017, C. hybrida cultivars ?Pampa Salmón INTA? and ?Overá Fucsia INTA? in a production greenhouse at Buenos Aires, Argentina, displayed virus-like symptoms, including leaf mosaic and growth retardation. Samples from symptomatic leaf tissue were collected from 20 plants of C. hybrida cultivar Overá Fucsia INTA and tested by indirect ELISA using polyclonal antibodies against potyviruses (BIOREBA Poty group test). The results of that study revealed that all samples were positive for a potyvirus. Reverse transcription polymerase chain reaction (PCR) with degenerate primers was performed to identify this potyvirus. Total RNA was extracted from symptomatic leaves of one ELISA-positive sample using TRIzol reagent, and cDNA was synthesized following the manufacturer?s instructions, using SuperScript III reverse transcription and primer AP from a 3′ rapid amplification of cDNA end kit (Thermo Fisher Scientific). The universal Potyviridae S-primer (Chen et al. 2001) and the abridged universal amplification primer (Thermo Fisher Scientific) were used to amplify a ∼1.7-kb PCR product spanning the nuclear NIb and the coat protein cistrons and the 3′ untranslated region with platinum Pfx DNA polymerase (Thermo Fisher Scientific). This ∼1.7-kb PCR product was cloned into pGEM-T Easy vector (Promega) and sequenced on an ABI 3500 XL automated sequencer. The 1,772-nt nucleotide sequence was deposited in GenBank database under the accession number MH880833. A BLASTn analysis of the 1,772-nt region of the virus isolate with the nucleotide sequences available in the GenBank database showed 82 to 88% nucleotide identity with different PVY isolates. The highest nucleotide identities were 88% with PVY (KC823271) isolated from Nicotiana tabacum in Brazil and 83% with PVY (KC296439) isolated from tobacco in China. At the amino acid level, the 480 amino acid partial polyprotein sequence showed 93% identity with the same Brazilian isolate (AGX27991) and 88% with the Chinese isolate (AGH27746). PVY complex includes five nonrecombinant strains and 36 recombinant patterns, presenting a challenge for strain typing (Green et al. 2018). The identification of the calibrachoa-infecting PVY strain is vital for resistant-cultivar selection, and therefore it should be addressed in future studies. To our knowledge, this is the first report of PVY as a pathogen of Calibrachoa in Argentina.Fil: Tombion, Leticia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Floricultura; ArgentinaFil: Alderete, Luciano Martín. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Floricultura; ArgentinaFil: Perez de la Torre, Mariana Cecilia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Floricultura; ArgentinaFil: Agrofoglio, Yamila Carla. 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: Delfosse, Verónica 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; ArgentinaFil: Distefano, Ana Julia. 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: Soto, María Silvina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación de Recursos Naturales. Instituto de Floricultura; Argentin

Arginine methylation of SM-LIKE PROTEIN 4 antagonistically affects alternative splicing during Arabidopsis stress responses

Agrofoglio YC, Iglesias MJ, Perez-Santangelo S, et al. Arginine methylation of SM-LIKE PROTEIN 4 antagonistically affects alternative splicing during Arabidopsis stress responses. Plant Cell. 2024: koae051.Arabidopsis (Arabidopsis thaliana) PROTEIN ARGININE METHYLTRANSFERASE5 (PRMT5) post-translationally modifies RNA-binding proteins by arginine (R) methylation. However, the impact of this modification on the regulation of RNA processing is largely unknown. We used the spliceosome component, SM-LIKE PROTEIN 4 (LSM4), as a paradigm to study the role of R-methylation in RNA processing. We found that LSM4 regulates alternative splicing (AS) of a suite of its in vivo targets identified here. The lsm4 and prmt5 mutants show a considerable overlap of genes with altered AS raising the possibility that splicing of those genes could be regulated by PRMT5-dependent LSM4 methylation. Indeed, LSM4 methylation impacts AS, particularly of genes linked with stress response. Wild-type LSM4 and an unmethylable version complement the lsm4-1 mutant, suggesting that methylation is not critical for growth in normal environments. However, LSM4 methylation increases with abscisic acid and is necessary for plants to grow under abiotic stress. Conversely, bacterial infection reduces LSM4 methylation, and plants that express unmethylable-LSM4 are more resistant to Pseudomonas than those expressing wild-type LSM4. This tolerance correlates with decreased intron retention of immune-response genes upon infection. Taken together, this provides direct evidence that R-methylation adjusts LSM4 function on pre-mRNA splicing in an antagonistic manner in response to biotic and abiotic stress. Arginine methylation of the spliceosome component SM-LIKE PROTEIN 4 by PROTEIN ARGININE METHYLTRANSFERASE5 fine-tunes alternative splicing of genes to control stress responses in Arabidopsis

First Complete Genome Sequence of Potato leafroll virus from Argentina

In this study, we determined for the first time the complete genomicsequence 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.Fil: Barrios Barón, María Pilar. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Agrofoglio, Yamila Carla. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Delfosse, Verónica Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; Argentina. Universidad Nacional de San Martín; ArgentinaFil: Nahirñak, Vanesa. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: González de Urreta, Martín Salvador. 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; ArgentinaFil: Distéfano, Ana Julia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; Argentin