Project description:In this project we present the identification of NEDD8 S65 phosphorylation under mitochondrial and DNA double strand break (DSB) stress conditions. Relative comparison revealed elevated levels of pNEDD8 under mitochondrial stress and reduced levels of pNEDD8 under DSB stress.
Project description:Rice is susceptible to both heat and drought stress, in particular during flowering and grain filling, when both grain yield and quality may be severely compromised. However, under field conditions, these two stresses rarely occur separately. Under well-watered conditions, plants avoid heat stress by transpirational cooling, while this is not possible under drought conditions. Although investigating combined heat and drought stress is clearly more agronomically relevant than analyzing the effects of the single stresses, only a few studies of this stress combination, in particular under field conditions, have been published. Furthermore, little is known about how plants respond during recovery from drought stress, which also determines plant survival. To address these knowledge gaps, three rice cultivars differing in heat and drought tolerance were grown in the field under control and drought conditions in three consecutive years. Drought was applied either during flowering or during early grain filling, resulting in simultaneous heat stress, leading to reduced grain yield and quality. Analysis by gas chromatography-mass spectrometry (GC-MS) showed distinct metabolic profiles for the three investigated organs (flag leaves, flowering spikelets, developing seeds). The metabolic responses of the plants also strongly differed between cultivars and organs, and between stress and rewatering conditions. Correlation analysis identified potential metabolic markers for grain yield and quality under combined heat and drought stress from stress- and rewatering-regulated metabolites and from metabolites with constitutive differences between the cultivars. These results show that GC-MS can resolve metabolic responses to combined heat and drought stress and subsequent rewatering in different organs of field-grown rice. The metabolite profiles can be used to identify potential marker metabolites for yield stability and grain quality that are expected to improve breeding efforts towards climate change resilient rice.
Project description:Mycobacterium avium complex (MAC), including Mycobacterium avium and Mycobacterium intracellulare (MI), accounts for a significant portion of nontuberculous mycobacterial lung disease affecting immunocompromised and lung structural disease patients. Adapting pathogens to a host-induced hostile environment is critical to establishing infection and persistence within the host. However, the cellular and molecular mechanisms of stress response for MAC still need to be elucidated. In this study, we analyzed the transcriptional profile of MI under acidic and oxidative stress conditions using RNA-seq. At the transcriptome level, 80 genes were shown [FC] ≥2.0 and p <0.05 under oxidative stress with 10 mM hydrogen peroxide. In detail, 77 genes were upregulated, while 3 genes were downregulated. Also, 878 genes were shown [FC] ≥2.0 and p <0.05 under acidic stress with pH 4.5. Among these genes, 339 were upregulated, while 539 were downregulated. Functional analysis revealed the activation of several pathways, including nitrogen and sulfur metabolism, under acidic stress conditions. On the contrary, oxidative stress conditions activated DNA replication and repair pathways. Our data demonstrate the activation of nitrogen and sulfur metabolism in MAC infection, which could be crucial for persistence and survival under stress conditions encountered within the host during infection. In conclusion, this study suggests the importance of stress responses in MAC pathogenesis and identifies potential therapeutic target pathways.