Explore the vast range of titles available.

Background Agrobacterium -mediated transformation is a fundamental method for the genetic modification of plants. However, several important crops and medicinal plants are recalcitrant to this process, hindering the application of modern functional genomics and genetic improvement tools. Hypericum perforatum L. (St. John’s wort), a valuable medicinal plant due to its secondary metabolites, is particularly recalcitrant to transformation mediated by Agrobacterium tumefaciens , and the molecular basis for this resistance remains unclear. This study was conducted to investigate the defense responses of H. perforatum after co-cultivation with A. tumefaciens and Agrobacterium rhizogenes through an integrative transcriptomic and metabolomic approach. Results Transcriptome profiling revealed extensive reprogramming of gene expression in response to both Agrobacterium strains. Core genes for signal transduction, defense responses, transcriptional regulation and biosynthesis of secondary metabolites were strongly differentially expressed. In particular, WRKY, MYB and ERF transcription factor-encoding genes were induced, reflecting their role in triggering plant immunity. The upregulation of genes related to xanthone biosynthesis and the associated downregulation of flavonoid metabolism genes indicate a metabolic Shift towards xanthone production. Metabolomic analyses consistent with these results showed a striking increase in defense-related xanthones such as 6-deoxyisojacareubin, hyperxanthone E and gemixanthone A after treatment with Agrobacterium . Conclusions H. perforatum possesses a controlled defense response to Agrobacterium that involves the transcriptional induction of defense signals and the accumulation of antimicrobial xanthones. The suppression of flavonoid biosynthesis also indicates a redirection of resources towards more efficient defense compounds. These results are important to elucidate the molecular basis of recalcitrance of H. perforatum transformation and to identify the role of pre-existing and inducible immunity in limiting Agrobacterium -mediated gene transfer.

The initiation of flowering is an important developmental transition as it marks the beginning of the reproductive phase in plants. The MADS-box transcription factors (TFs) FLOWERING LOCUS C (FLC) and SHORT VEGETATIVE PHASE (SVP) form a complex to repress the expression of genes that initiate flowering in Arabidopsis. Both TFs play a central role in the regulatory network by conferring seasonal patterns of flowering. However, their interdependence and biological relevance when acting as a complex have not been extensively studied. We characterized the effects of both TFs individually and as a complex on flowering initiation using transcriptome profiling and DNA-binding occupancy. We find four major clusters regulating transcriptional responses, and that DNA binding scenarios are highly affected by the presence of the cognate partner. Remarkably, we identify genes whose regulation depends exclusively on simultaneous action of both proteins, thus distinguishing between the specificity of the SVP:FLC complex and that of each TF acting individually. The downstream targets of the SVP:FLC complex include a higher proportion of genes regulating floral induction, whereas those bound by either TF independently are biased towards floral development. Many genes involved in gibberellin-related processes are bound by the SVP:FLC complex, suggesting that direct regulation of gibberellin metabolism by FLC and SVP contributes to their effects on flowering. The regulatory codes controlled by SVP and FLC were deciphered at the genome-wide level revealing substantial flexibility based on dependent and independent DNA binding that may contribute to variation and robustness in the regulation of flowering.

There are differences in the adoption rates of less invasive surfactant administration (LISA) worldwide. We aimed to describe and analyze the process of LISA introduction at the country level. A standardized training program (33 courses covering >500 neonatologists) was followed by a cohort study. Data regarding consecutive LISA procedures were acquired over 12 months in 31 tertiary neonatal centers, using a dedicated on-line platform. Of 500 LISA procedures, 75% were performed by specialists and 25% by residents. The mean percentage share of LISA in all surfactant therapies was 24%, which represents a 6-fold increase compared to previous years. After 12 months, 76% of the procedures were rated \"easy/very easy\" vs 59% at baseline (p<0.05). Surfactant re-treatment rate was 15%. Twenty-three percent of infants required mechanical ventilation within 72 hours of life. Oxygen desaturation and surfactant reflux were the most frequent complications. Unlike previous reports describing exclusive use of nasal continuous positive airway pressure (nCPAP) during LISA, majority of procedures (63%) were carried out using nasal intermittent positive pressure ventilation (NIPPV) or Bilevel Positive Airway Pressure (BiPAP). Efficacy of LISA with NIPPV or BiPAP was not significantly different from that with nCPAP (22.4% vs 24.5% of cases requiring intubation). Ventilation was provided with nasal cannulas or nasal masks (90%) and rarely with \"RAM\" cannulas or nasopharyngeal tubes. Rigid catheters were preferred (88.4%); tracheal insertion was successful at first attempt in 87% of cases. Majority of infants (79%) received no premedication prior to the procedure and almost all were given caffeine citrate. Median time of instillation was 1.5 minutes. The LISA procedure does not appear to be technically difficult to master. Training combining theory with practical exercises is an efficient implementation strategy. Variations in adoption rates indicate the need for additional, more personalized teachings in some centers.

Despite numerous studies aimed at unraveling the genetic background of barley’s response to abiotic stress, the modulation of the transcriptome induced by combinatorial drought and increased temperature remains largely unrecognized. Very limited studies were done, especially on the flag leaf, which plays an important role in grain filling in cereals. In the present study, transcriptome profiles, along with chlorophyll fluorescence parameters and yield components, were compared between barley genotypes with different flag leaf sizes under single and combined drought and heat stress. High-throughput mRNA sequencing revealed 2,457 differentially expressed genes, which were functionally interpreted using Gene Ontology term enrichment analysis. The transcriptomic signature under double stress was more similar to effects caused by drought than by elevated temperature; it was also manifested at phenotypic and chlorophyll fluorescence levels. Both common and stress-specific changes in transcript abundance were identified. Genes regulated commonly across stress treatments, determining universal stress responses, were associated, among others, with responses to drought, heat, and oxidative stress. In addition, changes specific to the size of the flag leaf blade were found. Our study allowed us to identify sets of genes assigned to various processes underlying the response to drought and heat, including photosynthesis, the abscisic acid pathway, and lipid transport. Genes encoding LEA proteins, including dehydrins and heat shock proteins, were especially induced by stress treatments. Some association between genetic composition and flag leaf size was confirmed. However, there was no general coincidence between SNP polymorphism of genotypes and differential expression of genes induced by stress factors. This research provided novel insight into the molecular mechanisms of barley flag leaf that determine drought and heat response, as well as their co-occurrence.

The iodine-131 (I-131) content in the thyroid of staff members working with this radionuclides has been measured with about 500 employees in about 25 hospital's departments of nuclear medicine performing therapy and diagnosis of thyroid disease in Poland. The measurements were performed with portable detection unit for measurements of radioiodine. This is consist with scintillation detector sodium iodine activated by thallium (NaI(Tl)) - battery-powered and portable tube base Multichannel Analyzer Canberra UniSPEC. Based on direct measurements of the iodine content, the effective dose equivalent for workers due to inhalation of I-131 was estimated. All individuals actively working with iodine show measurable amounts of this isotopes in their thyroids. The average measured activity in the thyroid of the nuclear medicine staff was found to be equal at average 550 Bq within the range 70 Bq-2.5 kBq. There is no apparent correlation between the measured I-131 levels and risk categories. Nevertheless the technical and nuclear medicine staff show higher I-131 thyroid level comparing to hospital services staff. Calculated maximum committed effective dose for particular exposed person is <10% of 20 mSv/year. Int J Occup Med Environ Health. 2023;36(5):587-95.

Narrow-leafed lupin (NLL, Lupinus angustifolius L.) is a legume plant cultivated for grain production and soil improvement. Worldwide expansion of NLL as a crop attracted various pathogenic fungi, including Colletotrichum lupini causing a devastating disease, anthracnose. Two alleles conferring improved resistance, Lanr1 and AnMan , were exploited in NLL breeding, however, underlying molecular mechanisms remained unknown. In this study, European NLL germplasm was screened with Lanr1 and AnMan markers. Inoculation tests in controlled environment confirmed effectiveness of both resistance donors. Representative resistant and susceptible lines were subjected to differential gene expression profiling. Resistance to anthracnose was associated with overrepresentation of “GO:0006952 defense response”, “GO:0055114 oxidation–reduction process” and “GO:0015979 photosynthesis” gene ontology terms. Moreover, the Lanr1 (83A:476) line revealed massive transcriptomic reprogramming quickly after inoculation, whereas other lines showed such a response delayed by about 42 h. Defense response was associated with upregulation of TIR-NBS, CC-NBS-LRR and NBS-LRR genes, pathogenesis-related 10 proteins, lipid transfer proteins, glucan endo-1,3-beta-glucosidases, glycine-rich cell wall proteins and genes from reactive oxygen species pathway. Early response of 83A:476, including orchestrated downregulation of photosynthesis-related genes, coincided with the successful defense during fungus biotrophic growth phase, indicating effector-triggered immunity. Mandelup response was delayed and resembled general horizontal resistance.

Abiotic stresses occur more often in combination than alone under regular field conditions limiting in more severe way crop production. Stress recognition in plants primarily occurs in the plasma membrane, modification of which is necessary to maintain homeostasis in response to it. It is known that lipid transport proteins (ns-LTPs) participate in modification of the lipidome of cell membranes. Representative of this group, ns-LTP2.8, may be involved in the reaction to abiotic stress of germinating barley plants by mediating the intracellular transport of hydrophobic particles, such as lipids, helping to maintain homeostasis. The ns-LTP2.8 protein was selected for analysis due to its ability to transport not only linear hydrophobic molecules but also compounds with a more complex spatial structure. Moreover, ns-LTP2.8 has been qualified as a member of pathogenesis-related proteins, which makes it particularly important in relation to its high allergenic potential. This paper demonstrates for the first time the influence of various abiotic stresses acting separately as well as in their combinations on the change in the ns-LTP2 . 8 transcript, ns-LTP2.8 protein and total soluble protein content in the embryonal axes of germinating spring barley genotypes with different ns-LTP2 . 8 allelic forms and stress tolerance. Tissue localization of ns-LTP2 . 8 transcript as well as ns-LTP2.8 protein were also examined. Although the impact of abiotic stresses on the regulation of gene transcription and translation processes remains not fully recognized, in this work we managed to demonstrate different impact on applied stresses on the fundamental cellular processes in very little studied tissue of the embryonal axis of barley.

Plants can produce organs throughout their entire life from pluripotent stem cells located at their growing tip, the shoot apical meristem (SAM). At the time of flowering, the SAM of Arabidopsis thaliana switches fate and starts producing flowers instead of leaves. Correct timing of flowering in part determines reproductive success, and is therefore under environmental and endogenous control. How epigenetic regulation contributes to the floral transition has eluded analysis so far, mostly because of the poor accessibility of the SAM. Here we report the temporal dynamics of the chromatin modifications H3K4me3 and H3K27me3 and their correlation with transcriptional changes at the SAM in response to photoperiod-induced flowering. Emphasizing the importance of tissue-specific epigenomic analyses we detect enrichments of chromatin states in the SAM that were not apparent in whole seedlings. Furthermore, our results suggest that regulation of translation might be involved in adjusting meristem function during the induction of flowering. When plants flower, the shoot apical meristem switches fate to produce floral organs instead of leaves. Here You et al . perform tissue-specific epigenome profiling and show that during this transition changes in histone methylation are correlated with transcriptional responses in the meristem.

The advanced molecular tools provide critical inputs in uncovering the regulatory mechanisms underlying plants’ adaptation to abiotic stress. Presented holistic studies were done on the barley crown tissue being essential for plant performance under various environmental stimuli. To investigate the effect of brassinosteroids (BRs), the known players in stress management, on molecular response of this tissue to drought, the genotypes with different BRs signal transduction efficiency were employed. Large-scale transcriptomic and proteomic profiling confirmed the specific re-modeling of behavior of the BRs-insensitive barley uzu1 . a mutant under drought. On the other hand, a set of genes expressed independently of the genotype was identified, including dehydrin encoding genes. This study also uncovered the candidate genes to be linkers of phytohormones crosstalk. Importantly, we detected the converging upregulation of several proteins and encoding genes under drought, including late embryogenesis abundant proteins and chaperones; they represent a promising target for cereals’ improvement. Moreover, the greatest variation between genotypes in accumulation of BRs in the crown tissue exposed to drought was observed for castasterone. Presented multi-omics, high-throughput results enhanced the understanding of molecular response to drought in crown tissue. The new insight was provided into the relationships between gene expression, protein and phytohormone content in barley plants of different BRs signaling.

The root system is a key component for plant survival and productivity. In particular, under stress conditions, developing plants with a better root architecture can ensure productivity. The objectives of this study were to investigate the phenotypic variation of selected root- and yield-related traits in a diverse panel of spring barley genotypes. By performing a genome-wide association study (GWAS), we identified several associations underlying the variations occurring in root- and yield-related traits in response to natural variations in soil moisture. Here, we report the results of the GWAS based on both individual single-nucleotide polymorphism markers and linkage disequilibrium (LD) blocks of markers for 11 phenotypic traits related to plant morphology, grain quality, and root system in a group of spring barley accessions grown under field conditions. We also evaluated the root structure of these accessions by using a nondestructive method based on electrical capacitance. The results showed the importance of two LD-based blocks on chromosomes 2H and 7H in the expression of root architecture and yield-related traits. Our results revealed the importance of the region on the short arm of chromosome 2H in the expression of root- and yield-related traits. This study emphasized the pleiotropic effect of this region with respect to heading time and other important agronomic traits, including root architecture. Furthermore, this investigation provides new insights into the roles played by root traits in the yield performance of barley plants grown under natural conditions with daily variations in soil moisture content.