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The genus Dickeya consists of Gram-negative bacteria capable of causing soft rot symptoms in plants, which involves tissue breakdown, particularly in storage organs such as tubers, rhizomes, and bulbs. These bacteria are ranked among the top ten most relevant phytopathogens and seriously threaten economically valuable crops and ornamental plants. This study employs a genomic analysis approach to taxonomically classify and characterize the resistome and virulome of two new strains, CCRMP144 and CCRMP250, identified as Dickeya dadantii. These strains were found to be the causative agents of soft rot symptoms in chili pepper (Capsicum spp.) and lettuce (Lactuca sativa), respectively, in the northeastern region of Brazil. The methodology employed in silico techniques, including tetra correlation search (TCS) and Average Nucleotide Identity (ANI) analysis, in association with a phylogenomic tree inference. TCS and ANI analysis showed that the studied strains belong to the Dickeya dadantii species. The phylogenomic analysis grouped the studied strains in the D. dadantii clade. The genomic characterization demonstrates 68 virulence genes, 54 resistances of biocide and heavy metal genes, and 23 antibiotic resistance genes. As far as we know, this is the first genomic study with Brazilian D. dadantii strains. This study demonstrates the efficacy to taxonomic classification and provides insights into the pathogenesis, host range, and adaptability of these strains which are crucial for the development of more effective management and control strategies for soft rot diseases. [ABSTRACT FROM AUTHOR]

Cowpea (Vigna unguiculata (L.) Walp.) is an important legume cultivated mainly in regions with limited water availability across the African and American continents. Its productivity is significantly affected by environmental stresses. Thaumatin-like proteins (TLPs), which belong to the PR-5 (pathogenesis-related 5) protein family, are known to be responsive to both biotic and abiotic stresses. However, their role remains controversial, with some TLPs associated with plant defense (particularly against fungal infections) and others associated with abiotic stresses response. In this study, we evaluated the structural diversity and gene expression of TLPs in cowpea (VuTLPs) under different stress conditions, including biotic [mechanical injury followed by inoculation with Cowpea Aphid-borne Mosaic Virus (CABMV) or Cowpea Severe Mosaic Virus (CPSMV)] and abiotic (root dehydration). Genomic anchoring of VuTLPs revealed 34 loci encoding these proteins. Neighbor- joining analysis clustered the VuTLPs into three distinct groups. We identified 15 segmental duplication and 6 tandem duplication gene pairs, with the majority of VuTLP genes found to be under purifying selection. Promoter analysis associated VuTLPs with bHLH, Dof-type, and MYB- related transcription factors, supporting their diverse roles. Diversity in VuTLP function was also observed in their expression profiles under the studied stress conditions. Gene expression data showed that most VuTLPs are recruited within the first minutes after biotic stress imposition. For the root dehydration assay, the most transcripts were up-regulated 150 min post-stress. Moreover, the gene expression data suggested that VuTLPs exhibit functional specialization depending on the stress condition, highlighting their diverse roles and biotechnological potential. [ABSTRACT FROM AUTHOR]

Humans change the environment according to their need, causing modifications and affecting the local biodiversity. This work applied a set of dominant markers to test if urban populations of Cyperus ligularis L. (Cyperaceae) present less genetic diversity compared to forest/non‐urban populations, and if these environmental differences (land use) influence gene flow and population structure. Six available populations of C. ligularis were collected in different types of environments in Recife (Brazil). Overall 15 primers of DNA Amplification Fingerprinting and Inter Simple Sequence Repeat were applied and analyzed by proper statistics. The results revealed moderate genetic diversity, significant pairwise gene flow (Nem), and low differentiation between populations (FST). Land use had no direct correlation with genetic diversity or structure, however, an insular population showed higher differentiation from the remaining. Urban environments may not influence gene flow among C. ligularis populations in such environments; therefore, the genetic diversity is homogeneous in the analyzed area. [ABSTRACT FROM AUTHOR]

S. scabra is an important forage and extremophilic plant native to the Brazilian Caatinga semiarid region. It has only recently been subjected to omics-based investigations, and the generated datasets offer insights into biotechnologically significant candidates yet to be thoroughly examined. INSs (inositol and its derivatives) and RFO (raffinose oligosaccharide family) pathways emerge as pivotal candidates, given their critical roles in plant physiology. The mentioned compounds have also been linked to negative impacts on the absorption of nutrients in mammals, affecting overall nutritional intake and metabolism. Therefore, studying these metabolic pathways is important not just for plants but also for animals who depend on them as part of their diet. INS and RFO pathways in S. scabra stood out for their abundance of identified loci and enzymes. The enzymes exhibited genomic redundancy, being encoded by multiple loci and various gene families. The phylogenomic analysis unveiled an expansion of the PIP5K and GolS gene families relative to the immediate S. scabra ancestor. These enzymes are crucial for synthesizing key secondary messengers and the RFO precursor, respectively. Transcriptional control of the studied pathways was associated with DOF-type, C2H2, and BCP1 transcription factors. Identification of biological processes related to INS and RFO metabolic routes in S. scabra highlighted their significance in responding to stressful conditions prevalent in the Caatinga environment. Finally, RNA-Seq and qPCR data revealed the relevant influence of genes of the INS and RFO pathways in the S. scabra response to water deprivation. Our study deciphers the genetics and transcriptomics of the INS and RFO in S. scabra, shedding light on their importance for a Caatinga-native plant and paving the way for future biotechnological applications in this species and beyond. [ABSTRACT FROM AUTHOR]

Helicases, motor proteins present in both prokaryotes and eukaryotes, play a direct role in various steps of RNA metabolism. Specifically, SF2 RNA helicases, a subset of the DEAD-box family, are essential players in plant developmental processes and responses to biotic and abiotic stresses. Despite this, information on this family in the physic nut (Jatropha curcas L.) remains limited, spanning from structural patterns to stress responses. We identified 79 genes encoding DEAD-box RNA helicases (JcDHX) in the J. curcas genome. These genes were further categorized into three subfamilies: DEAD (42 genes), DEAH (30 genes), and DExH/D (seven genes). Characterization of the encoded proteins revealed a remarkable diversity, with observed patterns in domains, motifs, and exon–intron structures suggesting that the DEAH and DExH/D subfamilies in J. curcas likely contribute to the overall versatility of the family. Three-dimensional modeling of the candidates showed characteristic hallmarks, highlighting the expected functional performance of these enzymes. The promoter regions of the JcDHX genes revealed potential cis-elements such as Dof-type, BBR-BPC, and AP2-ERF, indicating their potential involvement in the response to abiotic stresses. Analysis of RNA-Seq data from the roots of physic nut accessions exposed to 150 mM of NaCl for 3 h showed most of the JcDHX candidates repressed. The protein–protein interaction network indicated that JcDHX proteins occupy central positions, connecting events associated with RNA metabolism. Quantitative PCR analysis validated the expression of nine DEAD-box RNA helicase transcripts, showing significant associations with key components of the stress response, including RNA turnover, ribosome biogenesis, DNA repair, clathrin-mediated vesicular transport, phosphatidyl 3,5-inositol synthesis, and mitochondrial translation. Furthermore, the induced expression of one transcript (JcDHX44) was confirmed, suggesting that it is a potential candidate for future functional analyses to better understand its role in salinity stress tolerance. This study represents the first global report on the DEAD-box family of RNA helicases in physic nuts and displays structural characteristics compatible with their functions, likely serving as a critical component of the plant's response pathways. [ABSTRACT FROM AUTHOR]