bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evolutionarily conserved surface residues constitute actin binding sites of tropomyosin
Authors: Barua Bipasha , Pamula Melissa C. , Hitchcock-DeGregori Sarah E. 
Published: June 2011

Tropomyosin (Tm) is a two-chained, α-helical coiled-coil protein that associates end-to-end to form a continuous strand along actin filaments and regulates the functions and stability of actin in eukaryotic muscle and nonmuscle cells. Mutations in Tm cause skeletal and cardiac myopathies. We applied a neoteric molecular evolution approach to gain insight into the fundamental unresolved question of what makes the Tm coiled coil an actin binding protein. We carried out a phylogenetic analysis of 70 coding sequences of Tm genes from 26 animal species, from cnidarians to chordates, and evaluated the substitution rates (ω) at individual codons to identify conserved sites. The most conserved residues at surface
b
,
c
,
f
heptad repeat positions were mutated in rat striated muscle αTm and expressed in
Escherichia coli
. Each mutant had 3–4 sites mutated to Ala within the first half or the second half of periods 2–6. Actin affinity and thermodynamic stability were determined in vitro. Mutations in the first half of periods 2, 4, and 5 resulted in the largest reduction in actin affinity (> 4-fold), indicating these mutations include residues in actin-binding sites. Mutations in the second half of the periods had a ≤ 2-fold effect on affinity indicating these residues may be involved in other conserved regulatory functions. The structural relevance of these results was assessed by constructing molecular models for the actin-Tm filament. Molecular evolution analysis is a general approach that may be used to identify potential binding sites of a protein for a conserved protein.
Clinical and prognostic effects of atrial fibrillation in heart failure patients with reduced and preserved left ventricular ejection fraction
Authors: Linssen Gerard C.M. , Rienstra Michiel , Jaarsma Tiny , Voors Adriaan A. , van Gelder Isabelle C. , Hillege Hans L. , van Veldhuisen Dirk J. 
Published: June 2011

AimsAtrial fibrillation (AF) is common in heart failure (HF), but few data regarding the prognostic relevance of AF are available in HF patients with preserved left ventricular ejection fraction (HF‐PEF). We aimed to study the clinical impact of AF vs. sinus rhythm (SR) in stabilized HF patients with reduced left ventricular ejection fraction (HF‐REF) and in those with preserved left ventricular ejection fraction (HF‐PEF).Methods and resultsWe studied 927 patients with stable HF, of whom 336 (36%) had AF. N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) concentrations were measured at baseline and patients were followed for 18 months. We compared time to first HF (re‐)hospitalization or death between patients with AF and SR.Atrial fibrillation was present at baseline in 215 (35%) patients with HF‐REF (mean LVEF 0.25 + 0.08) and in 121 (40%) patients with HF‐PEF (mean LVEF 0.50 + 0.09). Plasma NT‐proBNP levels were similar in AF and SR patients (median 2398 vs. 2532 pg/mL, P = 0.74). Atrial fibrillation was independently associated with elevated NT‐proBNP levels in HF‐PEF, but not in HF‐REF patients (multivariable B = 0.33, P= 0.047 and B = 0.03; P = 0.89, respectively). After 18 months of follow‐up, the presence of AF was an independent predictor of death or HF hospitalization in HF‐PEF (multivariable hazard ratio 1.49 (95% CI 1.04–2.14), P = 0.03), but not in HF‐REF patients (1.05 (CI 95% 0.80–1.38), P = 0.72).ConclusionAtrial fibrillation is equally common in patients with HF‐PEF and HF‐REF. In HF‐PEF, but not in HF‐REF patients, AF was associated with higher NT‐proBNP levels and was independently related to death or HF hospitalization.
Evolution of the PEBP Gene Family in Plants: Functional Diversification in Seed Plant Evolution
Authors: Karlgren Anna , Gyllenstrand Niclas , Källman Thomas , Sundström Jens F. , Moore David , Lascoux Martin , Lagercrantz Ulf 
Published: June 2011

AbstractThe phosphatidyl ethanolamine-binding protein (PEBP) gene family is present in all eukaryote kingdoms, with three subfamilies identified in angiosperms (FLOWERING LOCUS T [FT], MOTHER OF FT AND TFL1 [MFT], and TERMINAL FLOWER1 [TFL1] like). In angiosperms, PEBP genes have been shown to function both as promoters and suppressors of flowering and to control plant architecture. In this study, we focus on previously uncharacterized PEBP genes from gymnosperms. Extensive database searches suggest that gymnosperms possess only two types of PEBP genes, MFT-like and a group that occupies an intermediate phylogenetic position between the FT-like and TFL1-like (FT/TFL1-like). Overexpression of Picea abies PEBP genes in Arabidopsis (Arabidopsis thaliana) suggests that the FT/TFL1-like genes (PaFTL1 and PaFTL2) code for proteins with a TFL1-like function. However, PaFTL1 and PaFTL2 also show highly divergent expression patterns. While the expression of PaFTL2 is correlated with annual growth rhythm and mainly confined to needles and vegetative and reproductive buds, the expression of PaFTL1 is largely restricted to microsporophylls of male cones. The P. abies MFT-like genes (PaMFT1 and PaMFT2) show a predominant expression during embryo development, a pattern that is also found for many MFT-like genes from angiosperms. P. abies PEBP gene expression is primarily detected in tissues undergoing physiological changes related to growth arrest and dormancy. A first duplication event resulting in two families of plant PEBP genes (MFT-like and FT/TFL1-like) seems to coincide with the evolution of seed plants, in which independent control of bud and seed dormancy was required, and the second duplication resulting in the FT-like and TFL1-like clades probably coincided with the evolution of angiosperms.
Coping with Stresses: Roles of Calcium- and Calcium/Calmodulin-Regulated Gene Expression
Authors: Reddy Anireddy S.N. , Ali Gul S. , Celesnik Helena , Day Irene S. 
Published: June 2011

AbstractAbiotic and biotic stresses are major limiting factors of crop yields and cause billions of dollars of losses annually around the world. It is hoped that understanding at the molecular level how plants respond to adverse conditions and adapt to a changing environment will help in developing plants that can better cope with stresses. Acquisition of stress tolerance requires orchestration of a multitude of biochemical and physiological changes, and most of these depend on changes in gene expression. Research during the last two decades has established that different stresses cause signal-specific changes in cellular Ca2+ level, which functions as a messenger in modulating diverse physiological processes that are important for stress adaptation. In recent years, many Ca2+ and Ca2+/calmodulin (CaM) binding transcription factors (TFs) have been identified in plants. Functional analyses of some of these TFs indicate that they play key roles in stress signaling pathways. Here, we review recent progress in this area with emphasis on the roles of Ca2+- and Ca2+/CaM-regulated transcription in stress responses. We will discuss emerging paradigms in the field, highlight the areas that need further investigation, and present some promising novel high-throughput tools to address Ca2+-regulated transcriptional networks.
The Plasma Membrane of the Cyanobacterium Gloeobacter violaceus Contains Segregated Bioenergetic Domains
Authors: Rexroth Sascha , Mullineaux Conrad W. , Ellinger Dorothea , Sendtko Esther , Rögner Matthias , Koenig Friederike 
Published: June 2011

Abstract
The light reactions of oxygenic photosynthesis almost invariably take place in the thylakoid membranes, a highly specialized internal membrane system located in the stroma of chloroplasts and the cytoplasm of cyanobacteria. The only known exception is the primordial cyanobacterium Gloeobacter violaceus, which evolved before the appearance of thylakoids and harbors the photosynthetic complexes in the plasma membrane. Thus, studies on G. violaceus not only shed light on the evolutionary origin and the functional advantages of thylakoid membranes but also might include insights regarding thylakoid formation during chloroplast differentiation. Based on biochemical isolation and direct in vivo characterization, we report here structural and functional domains in the cytoplasmic membrane of a cyanobacterium. Although G. violaceus has no internal membranes, it does have localized domains with apparently specialized functions in its plasma membrane, in which both the photosynthetic and the respiratory complexes are concentrated. These bioenergetic domains can be visualized by confocal microscopy, and they can be isolated by a simple procedure. Proteomic analysis of these domains indicates their physiological function and suggests a protein sorting mechanism via interaction with membrane-intrinsic terpenoids. Based on these results, we propose specialized domains in the plasma membrane as evolutionary precursors of thylakoids.
Malonyl-CoA Synthetase, Encoded by ACYL ACTIVATING ENZYME13, Is Essential for Growth and Development of Arabidopsis
Authors: Chen Hui , Kim Hyun Uk , Weng Hua , Browse John 
Published: June 2011

Abstract
Malonyl-CoA is the precursor for fatty acid synthesis and elongation. It is also one of the building blocks for the biosynthesis of some phytoalexins, flavonoids, and many malonylated compounds. In plants as well as in animals, malonyl-CoA is almost exclusively derived from acetyl-CoA by acetyl-CoA carboxylase (EC 6.4.1.2). However, previous studies have suggested that malonyl-CoA may also be made directly from malonic acid by malonyl-CoA synthetase (EC 6.2.1.14). Here, we report the cloning of a eukaryotic malonyl-CoA synthetase gene, Acyl Activating Enzyme13 (AAE13; At3g16170), from Arabidopsis thaliana. Recombinant AAE13 protein showed high activity against malonic acid (K m = 529.4 ± 98.5 μM; V m = 24.0 ± 2.7 μmol/mg/min) but little or no activity against other dicarboxylic or fatty acids tested. Exogenous malonic acid was toxic to Arabidopsis seedlings and caused accumulation of malonic and succinic acids in the seedlings. aae13 null mutants also grew poorly and accumulated malonic and succinic acids. These defects were complemented by an AAE13 transgene or by a bacterial malonyl-CoA synthetase gene under control of the AAE13 promoter. Our results demonstrate that the malonyl-CoA synthetase encoded by AAE13 is essential for healthy growth and development, probably because it is required for the detoxification of malonate.
Gibberellin Regulates PIN-FORMED Abundance and Is Required for Auxin Transport–Dependent Growth and Development inArabidopsis thaliana
Authors: Willige Björn C. , Isono Erika , Richter René , Zourelidou Melina , Schwechheimer Claus 
Published: June 2011

AbstractPlants integrate different regulatory signals to control their growth and development. Although a number of physiological observations suggest that there is crosstalk between the phytohormone gibberellin (GA) and auxin, as well as with auxin transport, the molecular basis for this hormonal crosstalk remains largely unexplained. Here, we show that auxin transport is reduced in the inflorescences of Arabidopsis thaliana mutants deficient in GA biosynthesis and signaling. We further show that this reduced auxin transport correlates with a reduction in the abundance of PIN-FORMED (PIN) auxin efflux facilitators in GA-deficient plants and that PIN protein levels recover to wild-type levels following GA treatment. We also demonstrate that the regulation of PIN protein levels cannot be explained by a transcriptional regulation of the PIN genes but that GA deficiency promotes, at least in the case of PIN2, the targeting of PIN proteins for vacuolar degradation. In genetic studies, we reveal that the reduced auxin transport of GA mutants correlates with an impairment in two PIN-dependent growth processes, namely, cotyledon differentiation and root gravitropic responses. Our study thus presents evidence for a role of GA in these growth responses and for a GA-dependent modulation of PIN turnover that may be causative for these differential growth responses.
Simulation training methods to develop cultural awareness
Authors: Hurn Brian J. 
Published: June 2011

PurposeThis paper aims to review the simulation methods that are available for training to develop cultural awareness for business people, members of international NGOs, diplomatic staff and others working in the international environment, as well as teachers of international business subjects at universities. It provides examples of good practice with analysis of the effectiveness of the different training methods.Design/methodology/approachThe paper takes the form of a critical review of existing methods with comments on suitability, advantages and disadvantages and examples of good practice.FindingsThe development of cultural awareness and cultural sensitivity is of fundamental importance for those working in the international community. Various methods of simulating cultural scenarios can be used to prepare those going to live and work in this environment. The most effective methods involve experiential learning in real‐life scenarios.Practical implicationsThe methods described involve simulation exercises for use at various levels of business training. They are examples of real‐life cross‐cultural problem areas experienced by those working internationally.Originality/valueThe paper presents a comprehensive review of existing methods of simulation with examples of good practice and a statement of learning outcomes.
Accepting the challenge of leadership: a hero's journey
Authors: Steinhouse Robbie 
Published: June 2011

PurposeThis paper aims to describe a powerful coaching intervention for leadership development.Design/methodology/approachThe paper is based on the writer's experience as an executive coach working in leadership development.FindingsThe Hero's Journey intervention is especially powerful for work at the level of identity, for clients who feel at a deep, personal level that a new (or existing) role is not “really them”.Practical implicationsThe tool will make it easier to promote staff within an organisation. It will help people with potential, but who have “attitude problems”, to accept responsibility. As a formal process, it needs to be carried out by a professional coach or trainer, though the implications of it are of interest to anyone managing others through (or themselves undergoing) a process of personal change.Originality/valueThe process itself is not original to the author, but its use in business coaching is still uncommon. The point of the paper is to stress its ease of use, power and wide range of applications, and to make it more commonly used.
ST‐IM model: a whole brain approach to implementation
Authors: Deshpande Prasad , Baxi Suhas 
Published: June 2011

PurposeThe purpose of the paper is to present a practical case study of a mid‐size Indian organisation, where the whole brain thinking (WBT) approach has been successfully used to align strategy to development needs, based on a simple but powerful model, the ST‐IM™; the authors also share how WBT has been useful in increasing the effectiveness of the implementation of key strategic projects.Design/methodology/approachThe approach was to engage the wider team (leadership and managers) in the formulation and implementation of strategic goals by making them aware of their thinking preferences/mindsets through a collaborative approach to working. Project teams were then formed and the project plan – right from the project definition to the milestones – was created, using the whole brain walk around. This approach helped managers to identify “gaps” and bridge these gaps. The Herrmann Brain Dominance Instrument (HBDI®) was used as a tool to “colour” the organisation (the leadership team and all managers).FindingsThere was a high degree of acceptance of the WBT concept and the HBDI profiles generated among managers at all levels. This acceptance of their own thinking preferences as well as avoidances has led to managers being willing to become more flexible in their thinking – to become more “situationally whole brained” when required, leading to a visibly higher degree of success of implementation of projects.Originality/valueThe ST‐IM model demonstrates a practical way for organisations to engage the potential of a much wider team in the implementation of strategies.
Embedding collaboration through standards – part 2:the key aspects of BS 11000
Authors: Hawkins David , Little Bob 
Published: June 2011

PurposeThe purpose of this paper is to expand the debate around the catalysts required to develop, promote, implement and maintain effective collaborative practice.Design/methodology/approachA review of the benefits of business collaboration and partnering, with special reference to the world's first national standard in the world to address collaborative business relationships, BS 11000.FindingsIf appropriately integrated and executed, collaboration provides a valuable business model and enhanced performance. The adoption of a standard – BS 11000 – provides the foundation against which organisations can develop the right strategy and encourage sustainable relationships that can deliver value‐based performance. The BS 11000 standard provides consistency in developing a collaborative approach.Originality/valueThis paper explores the interdependence between operational practices and the behaviours that underpin performance and outcomes.
Evaluating effectiveness of a training programme with trainee reaction
Authors: Ghosh Piyali , Prasad Joshi Jagdamba , Satyawadi Rachita , Mukherjee Udita , Ranjan Rashmi 
Published: June 2011

PurposeThis paper aims to deal with evaluation of different parameters of an induction programme conducted by a transmission and distribution major in India. The study aims to indicate which aspects of the training programme need to be emphasised when devising induction programmes for managers and non‐managers, and to ascertain whether there is any significant difference in their reactions.Design/methodology/approachEvaluation has been done with the help of trainee reaction measured by a questionnaire. The statistical tools used include factor analysis to generate factors that influence trainee satisfaction and a t‐test to test the hypothesis that there will be a significant difference between managerial and non‐managerial levels in their satisfaction with different aspects of the programme.FindingsFactor analysis generated six factors, namely clarity of trainer, other facilities, venue of the programme, food served, practical application, and communication of trainer. The t‐test run on these factors shows a significant difference in means for only one factor, namely communication of trainer, which implies that managers could relate better to the trainer, given their intellectual superiority.Research limitations/implicationsA larger sample size covering more units of the organisation would help in generalising the findings.Practical implicationsThe findings could help in developing an induction programme customised to meeting the needs of managers and non‐managers.Originality/valuePractitioners may use this paper to plan a common orientation programme for the healthy integration of managers and non‐managers and to ensure that there is a minimal gap between the satisfaction levels of the two groups.
Group mentoring best practices
Authors: Emelo Randy 
Published: June 2011

PurposeThis paper seeks to describe best practices for designing and implementing mentoring groups.Design/methodology/approachResearchers used a 12‐question survey and personal interviews to assess the relevancy and success of group mentoring. Best practices for design and implementation evolved out of this research.FindingsLearners would like more opportunities to engage in group mentoring and peer learning. This practice offers an attractive alternative to traditional training because it is fast and flexible, it is cost‐effective, and it fosters relational learning. Groups should be formed that focus on relevant topics related to learners' needs, without concern if groups meet face‐to‐face or virtually. Advisors should set the direction for the groups, create an engaging atmosphere, and provide good resources.Research limitations/implicationsFurther research with a larger survey population would be valuable, particularly as the use of group mentoring expands.Practical implicationsAllowing employees to spend more time on peer learning through group mentoring can provide organizations with a low‐cost method for sharing practical, contextualized knowledge that people can rapidly apply back on the job.Originality/valueAll content in this paper is new. Readers will discover best practices based on the latest research in group mentoring and collaborative learning.
The impact of organizational changes on psychological contracts
Authors: Freese Charissa , Schalk Rene , Croon Marcel 
Published: June 2011

PurposeThe purpose of this study is to add to the existing literature on the impact of organizational changes on psychological contracts by examining the exchange between employer and employee obligations and organizational commitment and intention to turnover in a causal model.Design/methodology/approachPsychological contracts of 450 health care workers were assessed in a three‐wave longitudinal design, covering a one‐year period. The Tilburg Psychological Contract Questionnaire measures perceived obligations with respect to Job Content, Career Development, Social Atmosphere, Organizational Policies and Rewards (perceived organizational obligations) and In‐role and Extra‐role Obligations (perceived employee obligations). Linear structural equation modeling was used to test the changes in psychological contracts and outcome variables over time, and also to investigate the changes in the relationships between the dependent and independent variables over time.FindingsThe results show that organizational changes negatively affect the fulfilment and violation of perceived organizational obligations. However, perceived employee obligations are not affected. The perceived fulfilment of Organizational Policies and violations of the psychological contract in general are most strongly affected.Originality/valueEmpirical longitudinal field research on the effects of organizational changes on psychological contracts is virtually non‐existent. This study is a valuable contribution to psychological contract research, because of the longitudinal nature of the study and the linear structural equation models that are used.