1,721,011 research outputs found
HARNESSING GENOME EDITING TO ELUCIDATE THE ROLE OF HISTONE VARIANT H2A.Z IN GRAPEVINE
Full text linkPlants continually encounter various environmental stresses that represent significant challenges to their growth, development, and survival. In
particular, grapevine, which is a perennial plant of great economic importance, is subjected to both abiotic stresses, such as drought and
extreme temperatures, and biotic stresses, including diseases like powdery (Erysiphe necator) or downy (Plasmopara viticola) mildew. Lastly, due to a long history of breeding programs, crops have developed the "domestication syndrome". This involves an imbalance in the plant use of resources towards growth and productivity, at the expense of resistance to pathogens and the ability to recruit beneficial microorganisms, such as mycorrhizae.
Epigenetic modifications, such as DNA methylation and histone modifications, play an important role in stress responsiveness. Histone
variants can be incorporated into nucleosomes in a targeted and replication independent manner thus influencing nucleosome structure and properties, gene transcription, DNA repair mechanisms and finally genome stability. Despite this, there is still much to be discovered about histone variants, especially on their role during plant-microorganism interactions. Currently, H2A.Z, one variant of the canonical histone H2A, seems to be the
most involved in these mechanisms. Indeed, in plant, H2A.Z enrichment in the nucleosome occurs at Transcription starting site (TSS) of active genes
and in the gene body of silent inducible genes. Plant mutants of histone H2A.Z variants that have been produced so far are viable, and therefore can
reveal the function of these chromatin regulators throughout the life of the plant. Recent advances in genome editing techniques have provided powerful tools for precise modification of the genome. Our study aim is to investigate the application of genome editing (CRISPR-Cas9) techniques to modulate the expression of H2A.Z genes in grapevine and elucidate their role in in the interaction between plant and microorganisms, both beneficial and pathogenic. Target genes of interest for editing have been identified and transformation efforts are underway, aimed at both downregulation and
overexpression of the H2A.Z genes. This will provide a wider knowledge of the role of H2A.Z in biotic interactions in grapevine
Multiple origins of the common chameleon in southern Italy
Full text linkThe common chameleon Chamaeleo chamaeleon is a Mediterranean lizard which has been introduced in many islands and its native origin in European countries is debated. Chameleons have been introduced in southern Italy, possibly from the Middle East and Tunisia. We conducted genetic analyses on mitochondrial DNA 16S gene on a larger sample. We observed a multiple origin for the Salento (Apulia, southern Italy) population, with individuals phylogenetically related to populations of North Africa and two areas in the Middle East. Some individuals may have been released before the 1950s and some others in the 1980s, improving the establishment success of this species
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Microbe-assisted crop improvement: a sustainable weapon to restore holobiont functionality and resilience
No full textIn the past years, breeding programs have been mainly addressed on pushing the commercial features, forgetting important traits, such as those related to environmental stress resilience, that are instead present in wild relatives. Among the traits neglected by breeding processes, the ability to recruit beneficial microorganisms that recently is receiving a growing attention due to its potentiality. In this context, this review will provide a spotlight on critical issues of the anthropocentric point of view that, until now, has characterized the selection of elite plant genotypes. Its effects on the plant-microbiome interactions, and the possibility to develop novel strategies mediated by the exploitation of beneficial root-microbe interactions, will be discussed. More sustainable microbial-assisted strategies might in fact foster the green revolution and the achievement of a more sustainable agriculture in a climatic change scenario
The four Ws of viruses: Where, Which, What and Why - A deep dive into viral evolution
No full textFor centuries, humanity has been captivated by evolution, seeking to unravel the origins of life and identify past patterns with future applications. Viruses, despite their obligate parasitic nature, are the most adaptable biological entities, surpassing cellular life in their variability and adaptability. While many theories about viral evolution exist, a consensus on their origins remains elusive. The quasispecies theory, however, has emerged as a leading framework for understanding viral evolution and, indirectly, their variability and adaptability. This theory illuminates how viruses regulate behaviours such as host range and their symbiotic or antagonistic interactions with hosts. This review delves into the most substantiated theories of viral evolution, addressing four fundamental questions relevant to virus ecology: Where did viruses originate? What factors drive viral evolution? What determines the virus host range? And why do viruses adopt pathogenic or mutualistic strategies? We will provide a comprehensive and up-to-date analysis that integrates diverse theoretical perspectives with empirical data, providing a holistic view of viral evolution and its implications for viral behaviour.This work has been supported by MicroBIO (Funding ID: 2021.0072–51886) and LegnoSano (Funding ID: 2023.0094–53737) projects funded by Cariverona foundation; AGER 3 Project, grant n° 2022-2903; This study was also carried out within the Agritech National Research Center and received funding from the Next-Generation EU (PIANO NAZIONALE D IRIPRESA E RESILIENZA (PNRR)—MISSIONE 4 COMPONENTE 2, INVESTIMENTO 1.4—D.D. 1032 June 17, 2022, CN00000022). Part of the work was conducted within the Shield4Grape project (Grant number 101135088) funded by the European Commission in the framework of the Horizon Europe program. This manuscript reflects only the authors' views and opinions, neither the European Union nor the European Commission can be considered responsible for them.
The authors thank Alison Garside for the manuscript English editing service.Peer reviewe
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