bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protein Storage Vacuoles Are Transformed into Lytic Vacuoles in Root Meristematic Cells of Germinating Seedlings by Multiple, Cell Type-Specific Mechanisms
Authors: Zheng Huiqiong , Staehelin L. Andrew 
Published: January 2011

AbstractWe have investigated the structural events associated with vacuole biogenesis in root tip cells of tobacco (Nicotiana tabacum) seedlings preserved by high-pressure freezing and freeze-substitution techniques. Our micrographs demonstrate that the lytic vacuoles (LVs) of root tip cells are derived from protein storage vacuoles (PSVs) by cell type-specific sets of transformation events. Analysis of the vacuole transformation pathways has been aided by the phytin-dependent black osmium staining of PSV luminal contents. In epidermal and outer cortex cells, the central LVs are formed by a process involving PSV fusion, storage protein degradation, and the gradual replacement of the PSV marker protein α-tonoplast intrinsic protein (TIP) with the LV marker protein γ-TIP. In contrast, in the inner cortex and vascular cylinder cells, the transformation events are more complex. During mobilization of the stored molecules, the PSV membranes collapse osmotically upon themselves, thereby squeezing the vacuolar contents into the remaining bulging vacuolar regions. The collapsed PSV membranes then differentiate into two domains: (1) vacuole “reinflation” domains that produce pre-LVs, and (2) multilamellar autophagosomal domains that are later engulfed by the pre-LVs. The multilamellar autophagosomal domains appear to originate from concentric sheets of PSV membranes that create compartments within which the cytoplasm begins to break down. Engulfment of the multilamellar autophagic vacuoles by the pre-LVs gives rise to the mature LVs. During pre-LV formation, the PSV marker α-TIP disappears and is replaced by the LV marker γ-TIP. These findings demonstrate that the central LVs of root cells arise from PSVs via cell type-specific transformation pathways.
Supercomplex Formation with Photosystem I Is Required for the Stabilization of the Chloroplast NADH Dehydrogenase-Like Complex in Arabidopsis
Authors: Peng Lianwei , Shikanai Toshiharu 
Published: January 2011

Abstract
In higher plants, the chloroplast NADH dehydrogenase-like complex (NDH) interacts with photosystem I (PSI) to form the NDH-PSI supercomplex via two minor light-harvesting complex I (LHCI) proteins, Lhca5 and Lhca6. Previously, we showed that in lhca5 and lhca6, NDH still associates with PSI to form smaller versions of the NDH-PSI supercomplex, although their molecular masses are far smaller than that of the full-size NDH-PSI supercomplex. In this study, we show that the NDH complex is present in the monomeric form in Arabidopsis (Arabidopsis thaliana) lhca5 lhca6, implying that NDH interacts with multiple copies of PSI. NDH subunit levels were slightly reduced in immature leaves and more drastically (approximately 50%) in mature leaves of the lhca5 lhca6 double mutant compared with the wild type. Chlorophyll fluorescence analyses detected NDH activity of lhca5 lhca6, suggesting that the supercomplex formation is not essential for NDH activity. However, the severe phenotypes of the lhca5 lhca6 proton gradient regulation5 triple mutant in both plant growth rate and photosynthesis suggest that the function of NDH was impaired in this mutant in vivo. Accumulation of NDH subunits was drastically reduced in lhca5 lhca6 when the light intensity was shifted from 50 to 500 μmol photons m−2 s−1. Furthermore, the half-life of NDH subunits, especially that of NDH18, was shorter in monomeric NDH than in the NDH-PSI supercomplex under the high-light conditions. We propose that NDH-PSI supercomplex formation stabilizes NDH and that the process is especially required under stress conditions.
Endoplasmic Reticulum– and Golgi-Localized Phospholipase A2 Plays Critical Roles in Arabidopsis Pollen Development and Germination
Authors: Kim Hae Jin , Ok Sung Han , Bahn Sung Chul , Jang Juno , Oh Sung Aeong , Park Soon Ki , Twell David , Ryu Stephen Beungtae , Shin Jeong Sheop 
Published: January 2011

Abstract
The phospholipase A2 (PLA2) superfamily of lipolytic enzymes is involved in a number of essential biological processes, such as inflammation, development, host defense, and signal transduction. Despite the proven involvement of plant PLA2s in many biological functions, including senescence, wounding, elicitor and stress responses, and pathogen defense, relatively little is known about plant PLA2s, and their genes essentially remain uncharacterized. We characterized three of four Arabidopsis thaliana PLA2 paralogs (PLA2-β, -γ, and -Δ) and found that they (1) are expressed during pollen development, (2) localize to the endoplasmic reticulum and/or Golgi, and (3) play critical roles in pollen development and germination and tube growth. The suppression of PLA2 using the RNA interference approach resulted in pollen lethality. The inhibition of pollen germination by pharmacological PLA2 inhibitors was rescued by a lipid signal molecule, lysophosphatidyl ethanolamine. Based on these results, we propose that plant reproduction, in particular, male gametophyte development, requires the activities of the lipid-modifying PLA2s that are conserved in other organisms.
Heterodimers of the Arabidopsis Transcription Factors bZIP1 and bZIP53 Reprogram Amino Acid Metabolism during Low Energy Stress
Authors: Dietrich Katrin , Weltmeier Fridtjof , Ehlert Andrea , Weiste Christoph , Stahl Mark , Harter Klaus , Dröge-Laser Wolfgang 
Published: January 2011

Abstract
Control of energy homeostasis is crucial for plant survival, particularly under biotic or abiotic stress conditions. Energy deprivation induces dramatic reprogramming of transcription, facilitating metabolic adjustment. An in-depth knowledge of the corresponding regulatory networks would provide opportunities for the development of biotechnological strategies. Low energy stress activates the Arabidopsis thaliana group S1 basic leucine zipper transcription factors bZIP1 and bZIP53 by transcriptional and posttranscriptional mechanisms. Gain-of-function approaches define these bZIPs as crucial transcriptional regulators in Pro, Asn, and branched-chain amino acid metabolism. Whereas chromatin immunoprecipitation analyses confirm the direct binding of bZIP1 and bZIP53 to promoters of key metabolic genes, such as ASPARAGINE SYNTHETASE1 and PROLINE DEHYDROGENASE, the G-box, C-box, or ACT motifs (ACTCAT) have been defined as regulatory cis-elements in the starvation response. bZIP1 and bZIP53 were shown to specifically heterodimerize with group C bZIPs. Although single loss-of-function mutants did not affect starvation-induced transcription, quadruple mutants of group S1 and C bZIPs displayed a significant impairment. We therefore propose that bZIP1 and bZIP53 transduce low energy signals by heterodimerization with members of the partially redundant C/S1 bZIP factor network to reprogram primary metabolism in the starvation response.
The Arabidopsis Intracellular Na+/H+ Antiporters NHX5 and NHX6 Are Endosome Associated and Necessary for Plant Growth and Development
Authors: Bassil Elias , Ohto Masa-aki , Esumi Tomoya , Tajima Hiromi , Zhu Zhu , Cagnac Olivier , Belmonte Mark , Peleg Zvi , Yamaguchi Toshio , Blumwald Eduardo 
Published: January 2011

Abstract
Intracellular Na+/H+ antiporters (NHXs) play important roles in cellular pH and Na+ and K+ homeostasis in all eukaryotes. Based on sequence similarity, the six intracellular Arabidopsis thaliana members are divided into two groups. Unlike the vacuolar NHX1-4, NHX5 and NHX6 are believed to be endosomal; however, little data exist to support either their function or localization. Using reverse genetics, we show that whereas single knockouts nhx5 or nhx6 did not differ from the wild type, the double knockout nhx5 nhx6 showed reduced growth, with smaller and fewer cells and increased sensitivity to salinity. Reduced growth of nhx5 nhx6 was due to slowed cell expansion. Transcriptome analysis indicated that nhx5, nhx6, and the wild type had similar gene expression profiles, whereas transcripts related to vesicular trafficking and abiotic stress were enriched in nhx5 nhx6. We show that unlike other intracellular NHX proteins, NHX5 and NHX6 are associated with punctate, motile cytosolic vesicles, sensitive to Brefeldin A, that colocalize to known Golgi and trans-Golgi network markers. We provide data to show that vacuolar trafficking is affected in nhx5 nhx6. Possible involvements of NHX5 and NHX6 in maintaining organelle pH and ion homeostasis with implications in endosomal sorting and cellular stress responses are discussed.
Distinct Roles of Protein Disulfide Isomerase and P5 Sulfhydryl Oxidoreductases in Multiple Pathways for Oxidation of Structurally Diverse Storage Proteins in Rice
Authors: Onda Yayoi , Nagamine Ai , Sakurai Mutsumi , Kumamaru Toshihiro , Ogawa Masahiro , Kawagoe Yasushi 
Published: January 2011

Abstract
In the rice (Oryza sativa) endosperm, storage proteins are synthesized on the rough endoplasmic reticulum (ER), in which prolamins are sorted to protein bodies (PBs) called type-I PB (PB-I). Protein disulfide isomerase (PDI) family oxidoreductase PDIL2;3, an ortholog of human P5, contains a conserved structural disulfide in the redox-inactive thioredoxin-like (TRX) domain and was efficiently targeted to the surface of PB-I in a redox active site–dependent manner, whereas PDIL1;1, an ortholog of human PDI, was localized in the ER lumen. Complementation analyses using PDIL1;1 knockout esp2 mutant indicated that the a and a′ TRX domains of PDIL1;1 exhibited similar redox activities and that PDIL2;3 was unable to perform the PDIL1;1 functions. PDIL2;3 knockdown inhibited the accumulation of Cys-rich 10-kD prolamin (crP10) in the core of PB-I. Conversely, crP10 knockdown dispersed PDIL2;3 into the ER lumen. Glutathione S-transferase-PDIL2;3 formed a stable tetramer when it was expressed in Escherichia coli, and the recombinant PDIL2;3 tetramer facilitated α-globulin(C79F) mutant protein to form nonnative intermolecular disulfide bonds in vitro. These results indicate that PDIL2;3 and PDIL1;1 are not functionally redundant in sulfhydryl oxidations of structurally diverse storage proteins and play distinct roles in PB development. We discuss PDIL2;3-dependent and PDIL2;3-independent oxidation pathways that sustain disulfide bonds of crP10 in PB-I.
Micronutrient adequacy of homemade complementary foods
Authors: Agbon C.A. , Onabanjo O.O. , Akinyemi C.O. 
Published: January 2011

PurposeChildhood under‐nutrition remains a major health problem in resource‐poor settings like the rural areas in Nigeria. The purpose of this paper is to determine the types and nutrient adequacy of complementary foods used in a rural area.Design/methodology/approachThe most frequently used (52 percent) homemade complementary food (HCF) in the area was studied, employing questionnaire, standardization of recipe and chemical analysis to evaluate the complementary food and to suggest improvement.FindingsTwo varieties of local beans (white and brown) were used in the preparation of HCF in the study area. They were either peeled to remove the coat or unpeeled. There was no significant difference (p<0.05) in the protein content of the HCF made from the two varieties. Using any of the beans unpeeled children between the ages of six and eight months meet their energy and protein requirement. The calcium, iron, and zinc contents of HCF from the two bean varieties were low.Originality/valueThis paper may be the first to evaluate HCF using mothers' method of preparation.
Developing a nutrition assessment tool for Irish pre‐schools
Authors: Johnston Molloy Charlotte , Corish Clare , Kearney John , Hayes Nóirín , Glennon Slattery Corina 
Published: January 2011

PurposeThe provision of nutritious food to children in full day care pre‐schools is essential to ensure adequate child growth and development. The purpose of this paper is to outline the development of a nutrition assessment tool (scored evaluation form (SEF)) for this setting, and describe the nutrition practice findings measured by this tool in full day child care in Ireland.Design/methodology/approachThis study involved two phases: first, a comprehensive literature review carried out on each criterion in the SEF to ensure best practice; and second, use of the SEF in full day care pre‐schools to assess their nutrition practice.FindingsUse of the SEF demonstrated that portion sizes provided to infants and toddlers were inadequate. Poor provision of iron containing, vegetable and dairy foods was noted, as were poor meal time practices. The phrasing of certain criteria needs modification to avoid misinterpretation of portion size.Research limitations/implicationsWith small modifications to clarify the portion size provided, the SEF can be used in the pre‐school setting to ascertain nutrition practice.Practical implicationsThe SEF requires testing to determine its utility as an intervention tool whereby its use may lead to positive changes in nutrition practice in the pre‐school setting.Originality/valueThis paper outlines the development of a nutrition practice assessment tool for the full day child care setting in Ireland and describes previously unknown data gathered using this tool.
The role of Mediterranean diet in health and disease: an updated mini review
Authors: Karampola Maria , Papandreou Dimitrios , Makedou Kelly 
Published: January 2011

PurposeThe purpose of this paper is to review the Mediterranean diet and its association to disease and health benefits derived from the adherence to it.Design/methodology/approachThe review includes the most updated studies found in PubMed all in relation to the adaptation of the Mediterranean diet.FindingsThe cardioprotection of Mediterranean diet has been established. A number of cancer types could be prevented by following the Mediterranean type diet and the specific ingredients of it are also investigated to find their impact on health. Longevity is also favored by the adoption of this dietary pattern as is the population group diagnosed with metabolic syndrome and mental health disorders. The results about its consumption and obesity need further investigation. Patients with HIV, being on specific treatment, are advised not to follow the Mediterranean diet.Originality/valueThis paper gives a concise, up‐to‐date overview to nutritionists and dietitians on the Mediterranean diet and its relation to health and disease.
Skills for creative industries graduate success
Authors: Bridgstock Ruth 
Published: January 2011

PurposeAlthough there is increasing evidence that the creative industries are essential to national economic growth as well as social and cultural well‐being, creative graduates often find it difficult to become established professionally. This study aims to investigate the value of career management competence and intrinsic career motivations (as elements of “protean career orientation”) in predicting positive graduate outcomes.Design/methodology/approachSelf‐report surveys were administered to 208 creative industries graduates from two Australian universities at two points in time: at course completion, and one year later.FindingsThe paper finds that individual career management competence and intrinsic work motivations, measured at course completion, were significant predictors of early career success, using both subjective and objective measures, measured one year later.Practical implicationsThis study suggests that an emphasis on student development beyond the traditional “key” employability skills may well be worthwhile. The paper also suggests a broad learning and teaching approach by which universities can encourage the development of student career identity, and thus engender student intrinsic career motivations and career self management skills and behaviours.Originality/valueThis is one of the first studies to demonstrate empirically a link between a particular set of skills and graduate outcomes. In addition, it provides insights into the role of student career motivations in positive transitions to the world of work in the creative industries.
Time allocations for study: evidence from Arts students in Australia
Authors: Hlavac Jim , Peterson Jim , Piscioneri Matthew 
Published: January 2011

PurposeThe primary purpose of this paper is to compare time availability and its allocation amongst Arts students. In addition it aims to match time availability and use with informants' resource preferences and the variables of language background and residential status.Design/methodology/approachA sample of 109 students completed quantitatively‐based electronic and paper‐copy surveys. Empirical data from primary informants form the basis of analysis.FindingsThe paper finds that over 90 per cent of informants have non‐study commitments and over half have commitments of six or more hours per week. The largest single group (35 per cent) has obligations of six to 14 hours per week. There is only a weak correlation between a higher number of commitments a lower amount of “out‐of‐class” time to engage with study obligations. Conversely, fewer extra‐curricular obligations does not automatically lead to a higher number of hours devoted to study. Differences in resource use are small: paper copy resources are universally popular, regardless of time commitments and allocations. Non‐English‐speaking background and international students tend to have fewer non‐study commitments and devote more time to study in general than English‐speaking background and local informants.Research limitations/implicationsResearch covers one of full‐time student informants' four units and does not elicit responses from all units studied by informants.Originality/valueWhile employment has been examined as a factor affecting student performance and time availability, few studies have matched time availability and declared time allocations to study. Further, time availability as a key feature of academic study is matched against variables highly relevant to today's student populations: resource mode use; language background; and residential status.
Relationship between occupational commitment and ascribed importance of organisational characteristics
Authors: Simola Sheldene 
Published: January 2011

PurposeThis purpose of this paper is to investigate the relationship between dimensions of commitment to the profession of business, and ascribed importance of various organisational characteristics to the first full‐time job following graduation.Design/methodology/approachBusiness administration students (n=446) completed surveys on dimensions of their commitment to the profession of business and the importance they ascribed to having certain organisational characteristics in their first full‐time job (n=132). Confirmatory factor analysis of commitment scales, principal component analysis of organisational characteristics, and canonical correlations were used.FindingsAffective occupational commitment was differentially, positively associated with the importance ascribed to working in an organisation that offers opportunities for professional development. Normative occupational commitment was differentially, positively associated with the importance ascribed to working in a reputable organisation that is devoted to diversity and social responsibility.Research limitations/implicationsAdditional evaluation using multi‐source and behavioural data would be useful.Practical implicationsKnowledge of the relationship between types of occupational commitment and desired organisational characteristics among university students could inform organisational positioning relative to recruitment.Originality/valueResults reported in this paper demonstrate the potential relevance of occupational commitment components into the processes of recruitment and applicant attraction among university students.
The management paradox
Authors: De Cuyper Nele , De Witte Hans 
Published: January 2011

PurposeThis paper aims to investigate associations between self‐rated employability (SRE) and affective organizational commitment and performance to probe the so‐called management paradox, namely the idea that SRE relates to performance, but also to reduced commitment. SRE concerns the workers' perception about all available (quantitative SRE) or instead better (qualitative SRE) job opportunities on the internal (internal SRE) and/or the external (external SRE) labour market. This leads to four types of SRE: internal quantitative SRE; internal qualitative SRE; external quantitative SRE; and external qualitative SRE.Design/methodology/approachAnalyses were based on a sample of 551 workers from nine organizations: a large Belgian organization providing human resource services, and eight schools. Hypotheses were tested with structural equation modeling, accounting also for sector differences.FindingsInternal quantitative SRE associated positively with affective organizational commitment – directly as well as indirectly – through internal qualitative SRE. External quantitative SRE associated negatively with affective organizational commitment through external qualitative SRE. However, a direct and positive relationship was established between external quantitative SRE and affective organizational commitment. Finally, affective organizational commitment associated positively with performance.Originality/valueThis study is among the first to empirically test and prove false the management paradox. Another strength is that this study advanced SRE as a multi‐dimensional construct.
The role of organisational commitment in the analysis of resistance to change
Authors: Peccei Riccardo , Giangreco Antonio , Sebastiano Antonio 
Published: January 2011

PurposeThis study aims to contribute to a better understanding of resistance to change (RTC) by examining the role played by organisational commitment (OC) as a potential predictor and moderator in the analysis of RTC.Design/methodology/approachFirst, alternative models of OC were developed, first as a co‐predictor of RTC, and then as a moderator of the relationship between key established antecedents of RTC and resistance itself. The main established antecedents of RTC examined included employees' perceptions of the benefits of change (PBC), their involvement in the change process (IIC), and their overall attitudes towards the change (ATC). The alternative OC models were tested using data from a sample of over 300 middle managers from an Italian public sector service provider company undergoing a radical process of change.FindingsResults showed that OC, along with PBC and IIC, had a significant negative direct and indirect effect on RTC. The indirect effect was mediated by employee attitudes to the change. Contrary to expectations, however, commitment did not moderate any of the antecedents‐RTC relationships.Research limitations/implicationsAlthough based on self‐report cross‐sectional data, this paper suggests that, while OC has a main significant effect on RTC, it does not have a moderator effect in relation to RTC.Practical implicationsThe results suggest that OC is not a substitute for the effective management of change, but rather that management would be well advised to give due consideration to both factors when planning and implementing change.Social implicationsThe implications outlined above apply to a wide range of change initiatives, including the implementation of major social and economic programmes.Originality/valueThis paper adds to existing knowledge in the area of RTC, showing that employee attitudes towards the change is a key mediating mechanism through which OC may help to reduce resistance.