Genetic mechanisms of the devious intruder Candidatus Liberibacter in citrus

HLB symptom progression may result from three types of dysfunction occurring in Ca.L.-infected citrus: (1) a carbohydrate disorder linked to disruption of the source-sink relationship, (2) perturbation of hormonal crosstalk involved in plant immune responses (JA-SA signaling crosstalk), and (3) changes in the rapid activation of detoxifying pathways (particularly GSTs). The development of innovative short- or long-term biotechnological tools that allow beneficial modulation of these three pathways will help increase Citrus tolerance to this devastating disease

Unexpected new lizard from the Late Cretaceous of southern South America sheds light on Gondwanan squamate diversity

The record of Cretaceous terrestrial lizards (Squamata) in South America is patchy, with seven species described from north-eastern and south-eastern Brazil, and few isolated records of iguanians and scincomorphans from the Argentinian Patagonia. Herein we describe a new genus and species of Cretaceous lizard, Paleochelco occultato gen. et sp. nov., based on a partial skull (MACN-Pv-N 120) discovered about three decades ago that was unnoticed in the Colección Paleovertebrados of the Museo Argentino de Ciencias Naturales ?Bernardino Rivadavia?. It comes from rocks of the Upper Cretaceous Bajo de la Carpa Formation (Neuquén Group) exposed at the Campus of the Universidad Nacional del Comahue, north of Neuquén City (Neuquén Province). The new taxon was included into a broad phylogenetic dataset of squamates and it was recovered around the base of Polyglyphanodontia in a constrained analysis using a total-evidence backbone. By contrast, the same, but topologically unconstrained analysis found Paleochelco occultato also around the base of Polyglyphanodontia but alternatively as the sister taxon to Polyglyphanodontia + Scleroglossa or as one of the sister taxa to the Mosasauria + Scleroglossa clade. The new finding, as well as other records from Argentina and Brazil, highlights a complex, still unrecovered, evolutionary history for lizards in the Mesozoic of South America.Fil: Martinelli, Agustín Guillermo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Agnolin, Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Ezcurra, Martin Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; Argentin

Autonomic Management of Networked Small-Medium Factories

The Chapter reports the achievements of a research project that is developing a software platform with a suite of autonomic services enabling every company in the network to move from a situation where it wastes valuable resources in struggling with its customers and suppliers, towards a rational business environment where communication becomes faster, and operation and collaboration more efficient. The ultimate objective of the project is to set-up, develop, experiment and promote the adoption of a new collaboration practice within networked factories taking advantage of the autonomic model applied to a suite of support software services

Gene regulatory networks elucidating huanglongbing disease mechanisms.

Next-generation sequencing was exploited to gain deeper insight into the response to infection by Candidatus liberibacter asiaticus (CaLas), especially the immune disregulation and metabolic dysfunction caused by source-sink disruption. Previous fruit transcriptome data were compared with additional RNA-Seq data in three tissues: immature fruit, and young and mature leaves. Four categories of orchard trees were studied: symptomatic, asymptomatic, apparently healthy, and healthy. Principal component analysis found distinct expression patterns between immature and mature fruits and leaf samples for all four categories of trees. A predicted protein - protein interaction network identified HLB-regulated genes for sugar transporters playing key roles in the overall plant responses. Gene set and pathway enrichment analyses highlight the role of sucrose and starch metabolism in disease symptom development in all tissues. HLB-regulated genes (glucose-phosphate-transporter, invertase, starch-related genes) would likely determine the source-sink relationship disruption. In infected leaves, transcriptomic changes were observed for light reactions genes (downregulation), sucrose metabolism (upregulation), and starch biosynthesis (upregulation). In parallel, symptomatic fruits over-expressed genes involved in photosynthesis, sucrose and raffinose metabolism, and downregulated starch biosynthesis. We visualized gene networks between tissues inducing a source-sink shift. CaLas alters the hormone crosstalk, resulting in weak and ineffective tissue-specific plant immune responses necessary for bacterial clearance. Accordingly, expression of WRKYs (including WRKY70) was higher in fruits than in leaves. Systemic acquired responses were inadequately activated in young leaves, generally considered the sites where most new infections occur

Proposal of a Genome Editing System for Genetic Resistance to Tomato Spotted Wilt Virus

Viruses provoke considerable economical losses in agriculture. New molecular approaches to develop genetic resistance based on translational genomics and precision genetic modifications are highly expected. The type II Clustered, Regularly Interspaced Palindromic Repeats (CRISPR) system including Cas9 nuclease represent a promising and very powerful tool to specifically modulate the expression and activity of genes involved in biotic stress responses. In this study, we describe an approach to develop a platform system based on CRISPR system for genome editing technology in tomato. Tomato is an excellent plant for this approach considering the high-quality genome sequence, the rapid life cycle, the highly efficient in vitro plant culture and transformation protocols, Genome editing can be used to allow resistance to Tomato Spotted Wilt Virus (TSWV) infections by the successful obtainment of two specific objectives: (1) Development of a Genome Editing (GE) system using CRISPR-Cas9 system in tomato (Objective 1) and (2) test the system in inducing genetic resistance to TSWV infections. First, it will be necessary to model the molecular dynamics of key host and pathogen proteins predicting how targeted mutations affect these interactions. Then these host players will be targeted by CRISPR-Cas9 technology. The obtained plants can be evaluated for their phenotypic resistance and deeply analyzed using "omic" platforms to gain insight into gene regulatory networks of plant resistance. Outcomes of the proposed project will be essentially three: (1) Identify host target proteins interacting with pathogenic proteins and model their dynamic interactions; (2) develop a platform technology usable to obtain resistant tomatoes to TSWV inducing targeted genetic modifications in the genome; (3) facilitate the adaption of this platform to the improvement of important traits in other specialty crops