VipariNama: Combining CRISPR and systemic virus-based vectors for rapid phenotyping of complex plant traits

A breeder's panacea would be to manipulate plant traits to their gusto e piacere(taste and pleasure). Tolerance to drought and salinity, resistance to pests and pathogens, selectiveresistance to herbicides, increased yield through timed flowering, and better nutritional or productive traits are some of the attributes crop breeders continuously aim to improve. The development of recent genome editing tools, most notable CRISPR/Cas9, promises faster and less expensive crop breeding. Many traits, including plant height and flowering time, are controlled by complex, multiloci genetic programs with both activation and repression mechanisms to tune plant development (Eshed and Lippman, 2019). Thus, there is a need for tools that allow rapid evaluation of spatial and temporal phenotypic outcomes resultingfrom gene expression level reprogramming.Fil: Calla, Bernarda. University of Illinois. Urbana - Champaign; Estados UnidosFil: Moreno, Javier Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; Argentin

Molecular mechanisms involved in functional macroevolution of plant transcription factors

Transcription factors (TFs) are key components of the transcriptional regulation machinery. In plants, they accompanied the evolution from unicellular aquatic algae to complex flowering plants that dominate the land environment. The adaptations of the body plan and physiological responses required changes in the biological functions of TFs. Some ancestral gene regulatory networks are highly conserved, while others evolved more recently and only exist in particular lineages. The recent emergence of novel model organisms provided the opportunity for comparative studies, producing new insights to infer these evolutionary trajectories. In this review, we comprehensively revisit the recent literature on TFs of nonseed plants and algae, focusing on the molecular mechanisms driving their functional evolution. We discuss the particular contribution of changes in DNA-binding specificity, protein–protein interactions and cis-regulatory elements to gene regulatory networks. Current advances have shown that these evolutionary processes were shaped by changes in TF expression pattern, not through great innovation in TF protein sequences. We propose that the role of TFs associated with environmental and developmental regulation was unevenly conserved during land plant evolution.Fil: Romani, Facundo Alihuen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Moreno, Javier Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; Argentin

Waking up for defense! Melatonin as a regulator of stomatal immunity in plants

Melatonin is a tryptophan-derived compound discovered in the late 1950s as a molecule produced by the pineal gland of most vertebrates. Melatonin gained notoriety in the 1970s when it was demonstrated that its production increased in humans during the night in a rhythmic fashion associated with sleep synchronization (Xie et al., 2017). Melatonin is a ubiquitous molecule produced by bacteria, fungi, plants, and animals. In plants, melatonin regulates a wide range of processes, such as seed germination, root and shoot growth, and production of secondary metabolites, and is involved in circadian cycle regulation (Arnao and Hernández-Ruiz, 2019). The recent identification of a melatonin receptor named PHYTOMELATONIN RECEPTOR1 (AtPMTR1) in the plant model Arabidopsis (Arabidopsis thaliana) demonstrated that melatonin also governs an AtPMTR1-dependent mechanism of stomatal closure (Wei et al., 2018). As stomatal closure is a well-known process utilized by plants to restrain the invasion of pathogens, usually referred to as stomatal immunity (Melotto et al., 2006), melatonin is now gaining attention for its capacity to mediate responses to biotic stress in plants (Moustafa-Farag et al., 2020). Unfortunately, the underlying molecular mechanisms of melatonin regulation of plant immunity remain largely unknown.Fil: Moreno, Javier Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Lattarulo Campos, Marcelo. Universidade Do Estado de Mato Grosso (unemat)

Gearing up the clock of hypocotyl growth!

To anticipate daily changes imposed by Earth?s ro-tation, organisms from all domains of life have evolvedan endogenous 24-h timer with daily rhythmic func-tions: the circadian clock. In plants, the first organisms where circadian dynamics were observed, the circadianclock processes daylength information to regulate awide range of physiological and developmental re-sponses (Greenham and McClung, 2015). Under nor-mal photoperiodic conditions, hypocotyl elongationis a robust response that can be observed to monitorthe circadian regulation of plant growth (Nusinowet al., 2011). However, the regulatory networks con-trolling this physiological mechanism remain poorlyunderstood.Fil: Moreno, Javier Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Campos, Marcelo Lattarulo. Instituto de Biociências, Universidade Federal de Mato; Brasi

Negative feedback control of jasmonate signaling by an alternative splice variant of JAZ10

The plant hormone jasmonate (JA) activates gene expression by promoting ubiquitin-dependent degradation of JAZ transcriptional repressor proteins. A key feature of all JAZ proteins is the highly conserved Jas motif, which mediates both JAZ degradation and JAZ binding to the transcription factor MYC2. Rapid expression of JAZ genes in response to JA is thought to attenuate JA responses, but little is known about the mechanisms by which newly synthesized JAZ proteins exert repression in the presence of the hormone. Here, we show that desensitization to JA is mediated by an alternative splice variant (JAZ10.4) of JAZ10 that lacks the Jas motif. Unbiased protein-protein interaction screens identified three related bHLH transcription factors (MYC2, MYC3, and MYC4) and the co-repressor NINJA as JAZ10.4-binding partners. We show that the N-terminal region of JAZ10.4 contains a cryptic MYC2-binding site that resembles the Jas motif, and that the ZIM motif of JAZ10.4 functions as a transferable repressor domain whose activity is associated with recruitment of NINJA. Functional studies showed that expression of JAZ10.4 from the native JAZ10 promoter complemented the JA-hypersensitive phenotype of a jaz10 mutant. Moreover, treatment of these complemented lines with JA resulted in rapid accumulation of JAZ10.4 protein. Our results provide an explanation for how the unique domain architecture of JAZ10.4 links transcription factors to a co-repressor complex, and suggest how JA-induced transcription and alternative splicing of JAZ10 pre-mRNA creates a regulatory circuit to attenuate JA responses.Fil: Moreno, Javier Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; Argentina. Michigan State University; Estados UnidosFil: Shyu, Christine. Michigan State University; Estados UnidosFil: Campos, Marcelo L.. Michigan State University; Estados UnidosFil: Patel, Lalita C.. Michigan State University; Estados UnidosFil: Chung, Hoo Sun. Michigan State University; Estados UnidosFil: Yao, Jian. Michigan State University; Estados UnidosFil: He, Sheng Hang. Michigan State University; Estados UnidosFil: Howe, Gregg A.. Michigan State University; Estados Unido

Un enfoque motivacional por medio de la gamificación en el ámbito universitario

Agregarle características lúdicas a una actividad no lúdica permite motivar a quienes participan de la misma, abordando las cosas de otro modo. La puntuación por cada actividad realizada y los rankings conformados con dichas puntuaciones, son el eslabón inicial de una serie de elementos que permiten, en este caso, gamificar una plataforma universitaria dedicada a la realización de ejercicios codificados en Lenguaje C. Estos ejercicios son validados automáticamente. En primera instancia se envían para su análisis a un compilador instalado en el servidor web y luego se ejecutan una seria de casos de prueba diseñados para detectar errores, que serán informados al alumno. El alumno accede a la plataforma web, denominada “Programados”, pudiendo codificar los ejercicios propuestos y visualizando los errores a corregir. La plataforma es actualmente utilizada por los alumnos de la materia “Elementos de Programación” que se dicta en el primer año de todas las ingenierías que se ofrecen en la Universidad Nacional de La Matanza (Buenos Aires, Argentina). El objetivo de este artículo es presentar la herramienta, los elementos de gamificación implementados y mostrar una experiencia que creemos más que exitosa, dado que el objetivo de la herramienta es motivar a los alumnos para que dediquen horas de práctica por fuera de la cursada. Programados se ofrece como un recurso adicional de uso no obligatorio y a pesar de ello su uso es masivo

Brucella Evades Macrophage Killing via VirB-dependent Sustained Interactions with the Endoplasmic Reticulum

The intracellular pathogen Brucella is the causative agent of brucellosis, a worldwide zoonosis that affects mammals, including humans. Essential to Brucella virulence is its ability to survive and replicate inside host macrophages, yet the underlying mechanisms and the nature of the replicative compartment remain unclear. Here we show in a model of Brucella abortus infection of murine bone marrow–derived macrophages that a fraction of the bacteria that survive an initial macrophage killing proceed to replicate in a compartment segregated from the endocytic pathway. The maturation of the Brucella-containing vacuole involves sustained interactions and fusion with the endoplasmic reticulum (ER), which creates a replicative compartment with ER-like properties. The acquisition of ER membranes by replicating Brucella is independent of ER-Golgi COPI-dependent vesicular transport. A mutant of the VirB type IV secretion system, which is necessary for intracellular survival, was unable to sustain interactions and fuse with the ER, and was killed via eventual fusion with lysosomes. Thus, we demonstrate that live intracellular Brucella evade macrophage killing through VirB-dependent sustained interactions with the ER. Moreover, we assign an intracellular function to the VirB system, as being required for late maturation events necessary for the biogenesis of an ER-derived replicative organelle

Propuesta estratégica de mejora en la implementación de los estándares mínimos del sistema de gestión de la seguridad y salud en el trabajo (SG-SST) en la empresa cooasucol para el primer semestre del 2019

El desarrollo del siguiente trabajo pretende presentar el plan de mejoramiento diseñado para la compañía COOSUACOL , el cual permita fortalecer las fallas encontradas en la matriz de análisis y calificación realizada frente a la implementación de estándares mínimos del Sistema de Gestión de Seguridad y Salud en el Trabajo (SG_SST). El enfoque planteado esta en cumplir con la legislación vigente planteada en: decreto 1443 de Junio de 2014 (Implementación del SG-SST), decreto 1072 del 2015 (único reglamentario del sector trabajo), el Decreto 171 de 2016 (prorroga implementación SG-SST), el Decreto 052 de 2017 (transición para la implementación de SGSST) y por último la una de las más relevantes, la resolución 0312 del 2019 (Dicta los estándares mínimos del SG-SST), Para el desarrollo de la propuesta, la metodología empleada es con base en la investigación cualitativa, la cual propone realizar atreves de mejoras que se fortalezca la salud y seguridad en el Trabajo en unión con el área de Talento Humano de la compañía.The development of the following work intends to present the improvement plan designed for the company COOSUACOL, which allows to strengthen the failures found in the analysis and qualification matrix carried out against the implementation of minimum standards of the Occupational Health and Safety Management System (SG_SST). The proposed approach is to comply with the current legislation proposed in: Decree 1443 of June 2014 (Implementation of the SG-SST), Decree 1072 of 2015 (only regulation of the labor sector), Decree 171 of 2016 (extends SG-SST implementation ), Decree 052 of 2017 (transition for the implementation of SGSST) and finally one of the most relevant, resolution 0312 of 2019 (Dictates the minimum standards of the SG-SST), For the development of the proposal, the methodology used is based on qualitative research, which proposes to make improvements that strengthen the health and safety at Work in conjunction with the area of ​​Human Talent of the company

The Intrinsically Disordered Protein CARP9 Bridges HYL1 to AGO1 in the Nucleus to Promote MicroRNA Activity

In plants, small RNAs (sRNA) are loaded into ARGONAUTE (AGO) proteins to fulfill their regulatory functions. Micro RNAs (miRNAs), one of the most abundant classes of endogenous sRNAs, are preferentially loaded into ARGONAUTE1 (AGO1). Such loading, long believed to happen exclusively in the cytoplasm, was recently proposed to also occur in the nucleus. Here we identified CONSTITUTIVE ALTERATIONS IN THE SMALL RNAS PATHWAYS9 (CARP9), a nuclear-localized, intrinsically disordered protein, as a factor promoting miRNA activity in Arabidopsis (Arabidopsis thaliana). Mutations in the CARP9-encoding gene led to a mild reduction of miRNAs levels, impaired gene silencing, and characteristic morphological defects, including young leaf serration and altered flowering time. Intriguingly, we found that CARP9 was able to interact with HYPONASTIC LEAVES1 (HYL1), but not with other proteins of the miRNA biogenesis machinery. In the same way, CARP9 appeared to interact with mature miRNA, but not with pri-miRNA, positioning it after miRNA processing in the miRNA pathway. CARP9 was also able to interact with AGO1, promoting its interaction with HYL1 to facilitate miRNA loading in AGO1. Plants deficient in CARP9 displayed reduced levels of AGO1-loaded miRNAs, partial retention of miRNA in the nucleus, and reduced levels of AGO1. Collectively, our data suggest that CARP9 might modulate HYL1AGO1 crosstalk, acting as a scaffold for the formation of a nuclear post pri-miRNA processing complex that includes at least HYL1, AGO1 and HSP90. In such a complex, CARP9 stabilizes AGO1 and mature miRNAs, allowing the proper loading of miRNAs in the effector complex.Fil: Tomassi, Ariel Hernán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Ré, Delfina Adela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Romani, Facundo Alihuen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Cambiagno, Damián Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Gonzalo, Lucía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Moreno, Javier Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Arce, Agustín Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; ArgentinaFil: Manavella, Pablo Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Agrobiotecnología del Litoral. Universidad Nacional del Litoral. Instituto de Agrobiotecnología del Litoral; Argentin

The outer membranes of Brucella spp. are resistant to bactericidal cationic peptides

The actions of polymyxin B, rabbit polymorphonuclear lysosome extracts, 14 polycationic peptides (including defensin NP-2, cecropin P1, lactoferricin B, and active peptides from cationic protein 18 and bactenecin), EDTA, and Tris on Brucella spp. were studied, with other gram-negative bacteria as controls. Brucella spp. were comparatively resistant to all of the agents listed above and bound less polymyxin B, and their outer membranes (OMs) were neither morphologically altered nor permeabilized to lysozyme by polymyxin B concentrations, although both effects were observed for controls. EDTA and peptides increased or accelerated the partition of the hydrophobic probe N-phenyl-naphthylamine into Escherichia coli and Haemophilus influenzae OMs but had no effect on Brucella OMs. Since Brucella and H. influenzae OMs are permeable to hydrophobic compounds (G. Martínez de Tejada and I. Moriyón, J. Bacteriol. 175:5273-5275, 1993), the results show that such unusual permeability is not necessarily related to resistance to polycations. Although rough (R) B. abortus and B. ovis were more resistant than the controls were, there were qualitative and quantitative differences with smooth (S) brucellae; this may explain known host range and virulence differences. Brucella S-lipopolysaccharides (LPSs) had reduced affinities for polycations, and insertion of Brucella and Salmonella montevideo S-LPSs into the OM of a Brucella R-LPS mutant increased and decreased, respectively, its resistance to cationic peptides. The results show that the core lipid A of Brucella LPS plays a major role in polycation resistance and that O-chain density also contributes significantly. It is proposed that the features described above contribute to Brucella resistance to the oxygen-independent systems of phagocytes