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Andronis, C.

Publications and source records attributed to Andronis, C..

5 recordsLinked to original sources

The Cretan Carob Virome

Carob (Ceratonia siliqua) is an important yet often underestimated Mediterranean tree species. Historically used as a sweetener by ancient Greeks and Arabs, it also supported populations during periods of famine. Beyond its cultural value, carob exhibits notable agronomic traits, including drought and temperature tolerance, soil erosion prevention, and potential contributions to rural development. Although a Cretan carob genome assembly has recently become available, little is known about pathogens associated with this species, particularly viruses. Here, we characterized the virome of carob trees in Crete using high throughput sequencing (HTS) and targeted molecular validation. We collected 134 leaf samples from 34 growers across the island four prefectures. HTS analysis revealed novel isolates of two Secoviridae members (Artichoke yellow ringspot virus - AYRSV) and Strawberry latent ringspot virus - SLRSV), as well as Soybean ilarvirus 1 (SolV1), a putative and incompletely characterized jivivirus, and a previously undescribed coguvirus of the family Phenuiviridae, all confirmed by PCR screening. Phylogenetic and sequence analyses support the classification of the coguvirus as a distinct viral species, for which we propose the name Carob coguvirus 1 (CaCoV1). To our knowledge, this study provides the first comprehensive characterization of the carob virome. These findings expand current knowledge of viral diversity in carob and establish a foundation for future epidemiological studies, certification of propagation material, and the sustainable expansion of carob cultivation in Crete and other Mediterranean regions.

microbiology↗

VIRP1 bromodomain shapes nuclear condensate formation and has a positive effect on PSTVd accumulation

O_LIViroids are small, non-coding RNAs that rely on host factors for replication, intracellular trafficking and systemic movement. VIRP1, a Bromodomain and Extra-terminal domain (BET) protein, has previously been implicated in Potato spindle tuber viroid (PSTVd) infection, yet its precise role and mode of action remain unresolved. C_LIO_LIIn this work, we highlight VIRP1 as the only Solanaceae BET protein containing a proline-rich domain, which overlaps with the PSTVd-binding site. VIRP1-deficient plants exhibit delayed flowering and increased ABA sensitivity, with differentially expressed genes enriched in stress-related pathways. C_LIO_LIVIRP1 forms condensates in planta and in vitro, consistent with phase-separation behaviour. Condensate morphology is altered by PSTVd RNA, deletion of the intrinsically disordered CTD and bromodomain mutations. C_LIO_LIVIRP1 is particularly important for the early establishment of PSTVd infection, while nuclear localization and bromodomain integrity are required for efficient viroid accumulation. By contrast, the disordered CTD region is dispensable for complementation of PSTVd accumulation. C_LIO_LIOur results support a model in which VIRP1 acts as a host nuclear factor that links stress-related functions, nuclear condensate formation and early viroid infection. C_LI

plant biology↗

dsRNAEngineer: a web-based tool of comprehensive dsRNA design for pest control

RNA interference (RNAi) is a form of gene silencing triggered by double-stranded RNA (dsRNA) that operates in all eukaryotic organisms, including insects, mites, nematodes and fungi. In the last two decades, many dsRNAs have been synthesized to silence the target genes for exploration of the underlying function in these pests. Some of them are lethal to pests or inhibit the growth of the pest population, leading to a new concept of pesticides. The generation of these environment-friendly pesticides requires precise in silico design of dsRNA molecules that are specific to target pests but do not target non-pest organisms. Current efforts for dsRNA design are mostly focused on gene sequence level, lacking comprehensive analysis of RNAi-based mode-of-action at the whole transcriptome level of given species, causing low efficiency and imprecise dsRNA target exploration. To address these limitations, we have created dsRNAEngineer, a publicly available online tool that allows a comprehensive and rational dsRNA design, incorporating hundreds of pests and non-pests transcriptomes. Developed functionalities include screen-target (screen conserved genes for co-targets of various pest species), on-target, off-target, and multi-target to generate optimal dsRNA for precise pest control. dsRNAEngineer is available at https://dsrna-engineer.cn/. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=138 SRC="FIGDIR/small/604585v1_ufig1.gif" ALT="Figure 1"> View larger version (55K): org.highwire.dtl.DTLVardef@9ee7fdorg.highwire.dtl.DTLVardef@90b015org.highwire.dtl.DTLVardef@11857eborg.highwire.dtl.DTLVardef@1340f18_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

Proteomic analysis revealed that the oomyceticide phosphite exhibits multi-modal action in an oomycete pathosystem.

BACKGROUNDPhytopathogenic oomycetes constitute some of the most devastating plant pathogens that cause significant crop and horticultural loss. Phytophthora cinnamomi is a phytopathogenic oomycete that causes dieback disease in native vegetation and a variety of crops. This pathogen can survive through harsh environmental conditions which gives it an advantage over its susceptible hosts. The only implemented chemical used to control P. cinnamomi is the oomyceticide phosphite. Despite its widespread use, the mode of action of phosphite is not well understood and it is unclear whether it works directly on the pathogen or through the host. Additionally, resistance to phosphite is emerging in P. cinnamomi isolates and other oomycete phytopathogens. RESULTSThe mode of action of phosphite on the pathogen and through a model host was investigated using label-free quantitative proteomics. In vitro treatment of P. cinnamomi with phosphite hinders growth by interfering with metabolism, signalling and gene expression, traits that are not observed in the tolerant isolate. When the model host L. angustifolius was treated with phosphite, enrichment of proteins that are associated with photosynthesis, carbon fixation and lipid metabolism in the host was observed. An increase in the production of a range of defence-related proteins was observed. CONCLUSIONWe hypothesise direct and indirect models of the multi-modal action of phosphite that directly targets the pathogen as well as alters plant metabolism and immune response.

biochemistry↗

Binary Relation Extraction from Biomedical Literature using Dependency Trees and SVMs

The goal of Biomedical relation extraction is to uncover high-quality relations from life science literature with diverse applications in the fields of Biology and Medicine. In the last decade, several methods can be found in published literature ranging from binary to complex relation extraction. In this work, we present a binary relation extraction system that relies on sentence level dependency features. We use a novel approach to map dependency tree based rules to feature vectors that can be used to train a classifier. We build a SVM classifier using these feature vectors and our experimental results show that it outperforms simple co-occurrence and rule-based systems. Through our experiments, using two 'real-world' examples, we quantify the positive impact of improved relation extraction on Literature Based Discovery.

bioinformatics↗