23 research outputs found

    Direct targets of the transcription factors ABA-Insensitive(ABI)4 and ABI5 reveal synergistic action by ABI4 and several bZIP ABA response factors

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    The plant hormone abscisic acid (ABA) is a key regulator of seed development. In addition to promoting seed maturation, ABA inhibits seed germination and seedling growth. Many components involved in ABA response have been identified, including the transcription factors ABA insensitive (ABI)4 and ABI5. The genes encoding these factors are expressed predominantly in developing and mature seeds, and are positive regulators of ABA mediated inhibition of seed germination and growth. The direct effects of ABI4 and ABI5 in ABA response remain largely undefined. To address this question, plants over-expressing ABI4 or ABI5 were used to allow identification of direct transcriptional targets. Ectopically expressed ABI4 and ABI5 conferred ABA-dependent induction of slightly over 100 genes in 11 day old plants. In addition to effector genes involved in seed maturation and reserve storage, several signaling proteins and transcription factors were identified as targets of ABI4 and/or ABI5. Although only 12% of the ABA- and ABI-dependent transcriptional targets were induced by both ABI factors in 11 day old plants, 40% of those normally expressed in seeds had reduced transcript levels in both abi4 and abi5 mutants. Surprisingly, many of the ABI4 transcriptional targets do not contain the previously characterized ABI4 binding motifs, the CE1 or S box, in their promoters, but some of these interact with ABI4 in electrophoretic mobility shift assays, suggesting that sequence recognition by ABI4 may be more flexible than known canonical sequences. Yeast one-hybrid assays demonstrated synergistic action of ABI4 with ABI5 or related bZIP factors in regulating these promoters, and mutant analyses showed that ABI4 and these bZIPs share some functions in plants

    Interaction between sugar and abscisic acid signalling during early seedling development in Arabidopsis

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    Sugars regulate important processes and affect the expression of many genes in plants. Characterization of Arabidopsis (Arabidopsis thaliana) mutants with altered sugar sensitivity revealed the function of abscisic acid (ABA) signalling in sugar responses. However, the exact interaction between sugar signalling and ABA is obscure. Therefore ABA deficient plants with constitutive ABI4 expression (aba2-1/35S::ABI4) were generated. Enhanced ABI4 expression did not rescue the glucose insensitive (gin) phenotype of aba2 seedlings indicating that other ABA regulated factors are essential as well. Interestingly, both glucose and ABA treatment of Arabidopsis seeds trigger a post-germination seedling developmental arrest. The glucose-arrested seedlings had a drought tolerant phenotype and showed glucose-induced expression of ABSCISIC ACID INSENSITIVE3 (ABI3), ABI5 and LATE EMBRYOGENESIS ABUNDANT (LEA) genes reminiscent of ABA signalling during early seedling development. ABI3 is a key regulator of the ABA-induced arrest and it is shown here that ABI3 functions in glucose signalling as well. Multiple abi3 alleles have a glucose insensitive (gin) phenotype comparable to that of other known gin mutants. Importantly, glucose-regulated gene expression is disturbed in the abi3 background. Moreover, abi3 was insensitive to sugars during germination and showed sugar insensitive (sis) and sucrose uncoupled (sun) phenotypes. Mutant analysis further identified the ABA response pathway genes ENHANCED RESPONSE TO ABA1 (ERA1) and ABI2 as intermediates in glucose signalling. Hence, three previously unidentified sugar signalling genes have been identified, showing that ABA and glucose signalling overlap to a larger extend than originally thought

    Patient relevant outcome 7 years after total hip replacement for OA - a prospective study

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    <p>Abstract</p> <p>Background</p> <p>To investigate prospectively the patient-relevant outcome 7 years after total hip replacement (THR) for osteoarthritis (OA).</p> <p>Methods</p> <p>219 consecutive patients (120 women) with primary OA, mean age 71 (range 50-92) were assigned for THR. They were examined preoperatively, at 3, 6, 12 months, and at 4, 5 and 7 years postoperatively with the self-administered questionnaires SF-36 and WOMAC. Supplementary questions regarding postoperative complications, general co-morbidity, social circumstances and patient satisfaction were asked at the three last follow-ups. A reference group, 117 subjects (67 women), mean age 72 (range 52-92) without hip complaints were recruited from the community and investigated at the same times.</p> <p>Results</p> <p>151/170 (89%) of the patients and 65/74 (88%) of the reference group participated at the 7 year follow-up. The best postoperative result was reported one year postoperatively. At the 7 year follow up there was a significant difference between the patients and controls in SF-36 physical function (PF) and role physical (RP) but not of WOMAC function. There was no difference in frequency of co-morbid conditions between those operated and the reference group, but those operated were in greater need of walking aid (46% vs. 8% p < 0.0001) and reported more regional and widespread pain (68% vs. 53% p < 0.05).</p> <p>Conclusion</p> <p>This study shows that in an unselected cohort the patients experience a similar health-related quality of life as a reference group of a similar age and sex structure 7 years after THR except for general physical function where the patients score worse.</p

    New-School brand creation and creativity – lessons from hip-hop and the global branded generation

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    Whilst academic marketing literature exists on the value of Hip-Hop as a marketing tool, there appears to be less on Hip-Hop’s philosophical roots and why it proves to be so effective. This study attempts to fill this gap, investigating the apparent natural synergy with brand theory – in that they are both able to captivate and engage consumer-centric sub-cultural groups. Findings indicate that Brands and Hip-Hop weave themselves into the fabrics of society - creating social capital and providing a way for individuals to connect with the world. Through metaphor, slang, symbolism and sampling, they: recycle and preserve aspects of culture; but in doing so, also innovate. Two critical success factors in both appear to be: the ratification of authenticity, and an encouragement towards shared ownership. However in contrast, Hip-Hop places precedence on overt and clear signalling of competitive intent. The methodology used is an Expert Delphi study – which also draws from a review of song lyrics, participant observation studies and in-depth interviews. This provides a basis for inductive reasoning and syllogisms. The aim is two-fold: to present a new Hip-Hop inspired model for brand creation; and secondly to offer an innovative approach to in-depth qualitative studies, using ‘Word Cloud’ software
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