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Abstract Phytophthora root rot, caused by oomycete pathogens in the Phytophthora genus, poses a significant threat to soybean productivity. While resistance mechanisms againstPhytophthora sojaehave been extensively studied in soybean, the molecular basis underlying immune responses toPhytophthora sansomeanaremains unclear. In this study, we investigated transcriptomic and epigenetic responses of two resistant (Colfax and NE2701) and two susceptible (Williams 82 and Senaki) soybean lines at four time points (2, 4, 8, and 16 h post inoculation [hpi]) afterP. sansomeanainoculation. Comparative transcriptomic analyses revealed a greater number of differentially expressed genes (DEGs) upon pathogen inoculation in resistant lines, particularly at 8 and 16 hpi. These DEGs were predominantly associated with defense response, ethylene, and reactive oxygen species‐mediated defense pathways. Moreover, DE transposons were predominantly upregulated after inoculation, and more of them were enriched near genes in Colfax than other soybean lines. Notably, we identified a long non‐coding RNA (lncRNA) within the mapped region of the resistance gene that exhibited exclusive upregulation in the resistant lines after inoculation, potentially regulating two flankingLURP‐one‐relatedgenes. Furthermore, DNA methylation analysis revealed increased CHH (where H = A, T, or C) methylation levels in lncRNAs after inoculation, with delayed responses in Colfax compared to Williams 82. Overall, our results provide comprehensive insights into soybean responses toP. sansomeana, highlighting potential roles of lncRNAs and epigenetic regulation in plant defense.
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Desiccation induces varied responses within a soil bacterial genus
Abstract Desiccation impacts a suite of physiological processes in microbes by elevating levels of damaging reactive oxygen species and inducing DNA strand breaks. In response to desiccation‐induced stress, microbes have evolved specialized mechanisms to help them survive. Here, we performed a 128‐day lab desiccation experiment on nine strains from three clades of an abundant soil bacterium,Curtobacterium. We sequenced RNA from each strain at three time points to investigate their response.Curtobacteriumwas highly resistant to desiccation, outlasting bothEscherichia coliand a famously DNA damage‐resistant bacterium,Deinococcus radiodurans. However, within the genus, there were also 10‐fold differences in survival rates among strains. Transcriptomic profiling revealed responses shared within the genus including up‐regulation of genes involved in DNA damage repair, osmolyte production, and efflux pumps, but also up‐regulation of pathways and genes unique to the three clades. For example, trehalose synthesis geneotsB, the chaperonegroEL, and the oxygen scavengerkatAwere all found in either one or two clades but not the third. Here, we provide evidence of considerable variation in closely related strains, and further elucidation of the phylogenetic conservation of desiccation tolerance remains an important goal for microbial ecologists.
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- Award ID(s):
- 2113004
- PAR ID:
- 10455459
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Environmental Microbiology
- Volume:
- 25
- Issue:
- 12
- ISSN:
- 1462-2912
- Format(s):
- Medium: X Size: p. 3075-3086
- Size(s):
- p. 3075-3086
- Sponsoring Org:
- National Science Foundation
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