522 research outputs found
Analiza roli genu HvABI5 w odpowiedzi na stres suszy u jęczmienia (Hordeum vulgare L.)
Praca zawiera artykuły w języku angielskim.Every year drought causes serious loss of crop yield due to the progressive climate changes. Therefore, there is an urgent demand for development of new cultivars with better tolerance to stress. The part of this process is identification and description of mechanisms which ensure plant adaptation to drought. Abscisic acid (ABA) is a main phytohormone regulating plant response to abiotic stresses, including drought. At the physiological level, ABA causes stomata closure and photosynthesis inhibition, whereas at the molecular level it regulates expression of stress-responsive genes. In Arabidopsis, ABA INSENSITIVE 5 (ABI5) and ABRE BINDING FACTORs/ABRE-BINDING PROTEINs (ABFs/AREBs) act as ABA-dependent transcription factors with BASIC LEUCINE ZIPPER (bZIP) domain. They regulate expression of genes associated with plant adaptation to unfavorable environmental conditions.
The aim of the presented PhD thesis was to describe the function of HvABI5, a barley (Hordeum vulagre) homolog of AtABI5 and AtABF/AREB, in response to drought and to identify putative target genes of HvABI5. The application of barley TILLING population developed at the Department of Genetics, University of Silesia in Katowice, enabled identification of hvabi5.d mutant carrying a G1751A point mutation in HvABI5 gene. The identified mutation caused arginine to lysine substitution at the 274 amino acid position which is close to the bZIP domain of HvABI5 protein. hvabi5.d showed a much lower sensitivity to ABA during seed germination than its parent variety ‘Sebastian’. It also exhibited decreased values of photosynthetic parameters: the performance index for the photochemical activity (PIABS) and the maximum quantum yield of primary photochemistry (φP0), together with increased level of osmolyte proline after ABA treatment at the early seedling stage. Based on hvabi5.d reaction to ABA, it was assumed that HvABI5 may be involved in regulation of barley response to the drought stress. After 5 days of water withdrawal and 10-day drought treatment, hvabi5.d showed a 13% higher value of Relative Water Content (RWC) parameter than ‘Sebastian’. Increased drought tolerance of hvabi5.d was related to the better membrane protection, higher flavonoid content (flavonols and anthocyanins) and faster stomatal closure than observed in the parent variety. Moreover, the known HvABI5 target genes: HVA1 and HVA22, as well as DEHYDRATION-RESPONSIVE FACTOR 1 (HvDRF1), encoding ABA-dependent transcription factor, showed the higher expression in mutant when compared to ‘Sebastian’ under drought. On the other side, hvabi5.d showed decreased chlorophyll content and lower values of photosynthetic parameters, PIABS and φP0, under drought. To verify if HvABI5 regulates response to drought in the ABA-dependent way, the expression of genes related to the ABA metabolism and signaling was analyzed under drought in both genotypes. Expression of key ABA-pathway genes differed between mutant and ‘Sebastian’ under stress. In response to drought hvabi5.d showed 2-20 times higher expression of genes involved in ABA biosynthesis and metabolism, HvNCED1 and HvBG8, and gene encoding main components of ABA signaling, HvSnRK2.1 and HvPP2C4. Moreover, the mutant showed 2-times higher endogenous content of ABA than its parent variety after drought treatment. Furthermore, in the promoters of HvNCED1, HvSnRK2.1 and HvPP2C4 putative binding sites for ABI5 were identified. The increased expression of HvNCED1 and HvSnRK2.1 and the faster stomatal closure was also observed in hvabi5.d after ABA treatment which confirms the ABA-dependent HvABI5 activity in barley response to drought.
Global transcriptome analysis using Agilent microarrays revealed differentially expressed genes (DEGs) between hvabi5.d mutant and its parent variety after application of stress. More genes (2688) were specifically up- or down-regulated in the mutant after 5- day decrease of soil moisture (drought onset) than after 10-day drought treatment (1959 genes). Among them were genes which could be related to the mechanisms responsible for increased drought tolerance of hvabi5.d. In order to identify putative HvABI5 target genes, the promoters of DEGs were analyzed for the presence of cis-elements ABA RESPONSIVE ELEMENT (ABRE) recognized by ABI5. ABRE elements were found in the promoters of 49 genes showing differentiated expression at drought onset and in the promoters of 48 genes showing differentiated expression after drought. Twenty-two selected HvABI5 putative target genes were selected and their expression after drought and ABA treatments was analyzed. It showed a different transcription activity of 12 genes between hvabi5.d and its parent variety under both treatments, which indicates that they may be regulated by HvABI5 in response to drought in the ABA-dependent way. Function of these putative HvABI5 target genes is associated with response to stress, phytohormone biosynthesis, transcription regulation, phosphorylation, lipid function and cell function. Only 5 of 22 analyzed genes, which are related to stress response, gibberellin response, pathogen defense and translation regulation, showed a different expression in the mutant only under drought treatment. This indicates that HvABI5 can also act in the scope of other signaling pathways. It has to be underlined that the identified potential HvABI5 target genes were not described in literature, and function of these genes was assigned based on GO terms and functional annotation available in the databases for sequences corresponding to their HORVU ID.
Taken together, the presented results indicate that HvABI5 regulates barley drought response in the ABA-dependent way. The role of HvABI5 is to regulate stress-responsive genes which are related to mechanisms ensuring plant adaptation to drought. Moreover, HvABI5 can participate in the regulation of ABA biosynthesis and signaling via a feedback loop in response to drought. It should be underlined that the mode of ABA-dependent HvABI5 action during regulation of seed germination and drought response is different
Tobacco Industry Attempts to Influence and Use the German Government to Undermine the WHO Framework Convention on Tobacco Control
Background Germany has been identified as one of a few high-income countries that opposed a strong Framework Convention on Tobacco Control (FCTC), the WHO's first global public health treaty. This paper examines whether the tobacco industry had influenced the German position on the FCTC.
Methods Analysis of previously confidential tobacco industry documents.
Results The tobacco industry has identified Germany as a key target within its global strategy against the FCTC. Building on an already supportive base, the industry appears to have successfully lobbied the German government, influencing Germany's position and argumentation on key aspects of the FCTC. It then used Germany in its efforts to weaken the FCTC. The evidence suggests that the industry enjoyed success in undermining the Federal Health Ministry's position and using Germany to limit the European Union negotiating mandate. The tactics used by the tobacco industry included the creation of controversy between the financial, trade and other ministries on one side and the health ministry on the other side, the use of business associations and other front groups to lobby on the industry's behalf and securing industry access to the FCTC negotiations via the International Standardization Organization.
Conclusion The evidence suggests that Germany played a major role in the tobacco industry's efforts to undermine the FCTC. Germany's position consistently served to protect industry interests and was used to influence and constrain other countries. Germany thus contributed significantly to attempts to weaken an international treaty and, in doing so, failed in its responsibility to advance global health
“It’s personal to me”:A qualitative study of depression in young people with CFS/ME
Background: Paediatric chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) has a prevalence of 0.4–2.4% and is defined as ‘generalised disabling fatigue persisting after routine tests and investigations have failed to identify an obvious underlying cause’. One-third of young people with CFS/ME have probable depression. Little is known about why depression develops, the relationship between depression and CFS/ME, or what treatment might be helpful. Methods: We conducted nine semi-structured interviews with young people with CFS/ME (aged 13–17 years, 8/9 female) and probable depression, covering perceived causes of depression, the relationship between CFS/ME and depression, and treatment strategies. Results: Most thought CFS/ME caused depression. Many discussed a cyclical relationship: low mood made CFS/ME worse. A sense of loss was common. CFS/ME restricted activities participants valued and changed systemic structures, causing depression. There was no single helpful treatment approach. Individualised approaches using combinations of cognitive behavioural therapy (CBT), medication, activity management and other strategies were described. Conclusion: This study suggests that depression may be secondary to CFS/ME in young people because of the impact of CFS/ME on quality of life. Clinicians treating young people with CFS/ME need to consider strategies to prevent development of depression, and research is needed into approaches that are effective in treating CFS/ME with co-morbid depression. </jats:sec
Inducible Siphoviruses in superficial and deep tissue isolates of Propionibacterium acnes
Background: Propionibacterium acnes is a commensal of human skin but is also known to be involved in certain diseases, such as acne vulgaris and infections of orthopaedic implants. Treatment of these conditions is complicated by increased resistance to antibiotics and/or biofilm formation of P. acnes bacteria. P. acnes can be infected by bacteriophages, but until recently little has been known about these viruses. The aim of this study was to identify and characterize inducible phages from P. acnes on a genetic and morphological basis. Results: More than 70% (65/92) of P. acnes isolates investigated have inducible phages, classified morphologically as Siphoviruses. The phages have a head of 55 nm in diameter and a tail of 145 155 nm in length and 9-10 nm in width. There was no difference in carriage rate of phages between P. acnes isolates from deep infections and isolates from skin. However, there was a significant lower carriage rate of phages in P. acnes biotype IB, mostly attributed to the low carriage rate of inducible phages in biotype IB isolated from deep tissue. Most phages have a strong lytic activity against all P. acnes isolates with inducible phages, but have less lytic activity against isolates that have no prophages. Phages only infected and lysed P. acnes and not other closely related propionibacteria. All phages could infect and lyse their non-induced parental host, indicating that these prophages do not confer superinfection immunity. The phages have identical protein pattern as observed on SDS-PAGE. Finally, sequencing of two phage genes encoding a putative major head protein and an amidase and showed that the phages could be divided into different groups on a genetic basis. Conclusion: Our findings indicate that temperate phages are common in P. acnes, and that they are a genetically and functionally homogeneous group of Siphoviruses. The phages are specific for P. acnes and do not seem to confer superinfection immunity
Extreme gas production in anthropogenic fibrous sediments: An overlooked biogenic source of greenhouse gas emissions
Fibrous sediments that originated from old pulp and paper industry emissions are recognized as a potential threat to the aquatic environment because they are highly contaminated. In addition, biogenic degradation of the organic material from so-called "fiberbanks" has a high potential to produce greenhouse gases (GHG). In this study, X-ray tomography, optical sensors and gas analyzers were used to identify and quantify the gas produced and released from samples of two different fiberbanks. We show that a finer fibrous structure allows the formation of larger gas bubbles and higher gas production rates compared to coarser material composed of wood pieces. High contents of methane (average 56% to 65%) and carbon dioxide (average 18% to 20%) were measured in the gas emitted from both types of fiberbank. Measured methane production rates from the fiberbanks samples are one to three orders of magnitude higher than previously reported rates from sediments within the studied temperature range (between 0.03 and 0.51 mu m CH4/h/g dw over 4.7 to 20 degrees C). The potential for methane and carbon dioxide production in the fiberbank volume likely present in Sweden is estimated to correspond to 7% of Sweden's total known GHG emissions for 2019. These findings show that fiberbanks have the potential to be a significant emitter of GHG. (C) 2021 The Author(s). Published by Elsevier B.V
A mouse model of cone photoreceptor function loss
During routine screening of mouse strains and stocks by the Eye Mutant Resource at The Jackson Laboratory for genetic mouse models of human ocular disorders, we identifie
Corporate Social Responsibility and Access to Policy Élites: An Analysis of Tobacco Industry Documents
Gary Fooks and colleagues undertook a review of tobacco industry documents and show that policies on corporate social responsibility can enable access to and dialogue with policymakers at the highest level
Updates on the Role of ABSCISIC ACID INSENSITIVE 5 (ABI5) and ABSCISIC ACID-RESPONSIVE ELEMENT BINDING FACTORs (ABFs) in ABA Signaling in Different Developmental Stages in Plants
The core abscisic acid (ABA) signaling pathway consists of receptors, phosphatases, kinases
and transcription factors, among them ABA INSENSITIVE 5 (ABI5) and ABRE BINDING
FACTORs/ABRE-BINDING PROTEINs (ABFs/AREBs), which belong to the BASIC LEUCINE ZIPPER
(bZIP) family and control expression of stress-responsive genes. ABI5 is mostly active in seeds
and prevents germination and post-germinative growth under unfavorable conditions. The activity
of ABI5 is controlled at transcriptional and protein levels, depending on numerous regulators, including
components of other phytohormonal pathways. ABFs/AREBs act redundantly in regulating
genes that control physiological processes in response to stress during vegetative growth. In this
review, we focus on recent reports regarding ABI5 and ABFs/AREBs functions during abiotic stress
responses, which seem to be partially overlapping and not restricted to one developmental stage in
Arabidopsis and other species. Moreover, we point out that ABI5 and ABFs/AREBs play a crucial
role in the core ABA pathway’s feedback regulation. In this review, we also discuss increased stress
tolerance of transgenic plants overexpressing genes encoding ABA-dependent bZIPs. Taken together,
we show that ABI5 and ABFs/AREBs are crucial ABA-dependent transcription factors regulating
processes essential for plant adaptation to stress at different developmental stages
Endoglycosidase treatment abrogates IgG arthritogenicity: Importance of IgG glycosylation in arthritis.
The glycosylation status of IgG has been implicated in the pathology of rheumatoid arthritis. Earlier, we reported the identification of a novel secreted endo-beta-N-acetylglucosaminidase (EndoS), secreted by Streptococcus pyogenes that specifically hydrolyzes the beta-1,4-di-N-acetylchitobiose core of the asparagine-linked glycan of human IgG. Here, we analyzed the arthritogenicity of EndoS-treated collagen type II (CII) -specific mouse mAb in vivo. Endoglycosidase treatment of the antibodies inhibited the induction of arthritis in (BALB/c x B10.Q) F1 mice and induced a milder arthritis in B10.RIII mice as compared with the severe arthritis induced by non-treated antibodies. Furthermore, EndoS treatment did not affect the binding of IgG to CII and their ability to activate complement, but it resulted in reduced IgG binding to Fc gamma R and disturbed the formation of stable immune complexes. Hence, the asparagine-linked glycan on IgG plays a crucial role in the development of arthritis
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