Dynamic Aha1 co‐chaperone binding to human Hsp90

Hsp90 is an essential chaperone that requires large allosteric changes to determine its ATPase activity and client binding. The co‐chaperone Aha1, which is the major ATPase stimulator in eukaryotes, is important for regulation of Hsp90's allosteric timing. Little is known, however, about the structure of the Hsp90/Aha1 complex. Here, we characterize the solution structure of unmodified human Hsp90/Aha1 complex using NMR spectroscopy. We show that the 214‐kDa complex forms by a two‐step binding mechanism and adopts multiple conformations in the absence of nucleotide. Aha1 induces structural changes near Hsp90's nucleotide‐binding site, providing a basis for its ATPase‐enhancing activity. Our data reveal important aspects of this pivotal chaperone/co‐chaperone interaction and emphasize the relevance of characterizing dynamic chaperone structures in solution.     

Spatially balanced sampling and ground‐level imagery for vegetation monitoring on reclaimed well pads

Land reclamation associated with natural gas development has become increasingly important to mitigate land surface disturbance in western North America. Since well pads occur on sites with multiple land use and ownership, the progress and outcomes of these efforts are of interest to multiple stakeholders including industry, practitioners and consultants, regulatory agents, private landowners, and the scientific community. Reclamation success criteria often vary within, and among, government agencies and across land ownership type. Typically, reclamation success of a well pad is judged by comparing vegetation cover from a single transect on the pad to a single transect in an adjacent reference site and data are collected by a large number of technicians with various field monitoring skills. We utilized “SamplePoint” image analysis software and a spatially balanced sampling design, called balanced acceptance sampling, to demonstrate how spatially explicit quantitative data can be used to determine if sites are meeting various reclamation success criteria and used chi‐square tests to show how sites in vegetation percent cover differ from a statistical standpoint. This method collects field data faster than traditional methods. We demonstrate how quantitative and spatially explicit data can be utilized by multiple stakeholders, how it can improve upon current reference site selection, how it can satisfy reclamation monitoring requirements for multiple regulatory agencies, how it may help improve future seed mix selection, and discuss how it may reduce costs for operations responsible for reclamation and how it may reduce observer bias.     

Diagnosing idiopathic learning disability: a cost-effectiveness analysis of microarray technology in the National Health Service of the United Kingdom

Array based comparative genomic hybridisation (aCGH) is a powerful technique for detecting clinically relevant genome imbalance and can offer 40 to > 1000 times the resolution of karyotyping. Indeed, idiopathic learning disability (ILD) studies suggest that a genome-wide aCGH approach makes 10–15% more diagnoses involving genome imbalance than karyotyping. Despite this, aCGH has yet to be implemented as a routine NHS service. One significant obstacle is the perception that the technology is prohibitively expensive for most standard NHS clinical cytogenetics laboratories. To address this, we investigated the cost-effectiveness of aCGH versus standard cytogenetic analysis for diagnosing idiopathic learning disability (ILD) in the NHS. Cost data from four participating genetics centres were collected and analysed. In a single test comparison, the average cost of aCGH was ￡442 and the average cost of karyotyping was ￡117 with array costs contributing most to the cost difference. This difference was not a key barrier when the context of follow up diagnostic tests was considered. Indeed, in a hypothetical cohort of 100 ILD children, aCGH was found to cost less per diagnosis (￡3,118) than a karyotyping and multi-telomere FISH approach (￡4,957). We conclude that testing for genomic imbalances in ILD using microarray technology is likely to be cost-effective because long-term savings can be made regardless of a positive (diagnosis) or negative result. Earlier diagnoses save costs of additional diagnostic tests. Negative results are cost-effective in minimising follow-up test choice. The use of aCGH in routine clinical practice warrants serious consideration by healthcare providers. Copyright statement The Corresponding Author has the right to grant on behalf of all authors and does grant on behalf of all authors, an exclusive licence (or non exclusive for government employees) on a worldwide basis to the BMJ Publishing Group Ltd, and its Licensees to permit this article (if accepted) to be published in BMJ editions and any other BMJPGL products and to exploit all subsidiary rights, as set out in our licence (bmj.com/advice/copyright.shtml). Authorship The authors included on this paper fulfil the criteria of authorship and no one who fulfils the criteria has been excluded from authorship. The authors made a substantial contribution to the conception, design, analysis and interpretation of data. They were involved in drafting the article or revising it critically for important intellectual content and approving the version to be published. Contributorship Sarah Wordsworth (Guarantor): Planning, conducting and reporting work, interpretation of data, drafting and revising article. James Buchanan: Conducting and reporting work, interpretation of data, revising article. Regina Regan: Completing costing questionnaire, providing protocol details, other costing information, interpretation of data, information about learning disability and genome imbalance and revising article. Val Davison: Completing costing questionnaire, providing protocol details, sharing overall laboratory experience and drafting article. Kim Smith: Completing costing questionnaire, providing protocol details, drafting article. Sara Dyer: Completing costing questionnaire and providing protocol details. Carolyn Campbell: Completing costing questionnaire and providing protocol details. Edward Blair: Critical appraisal of article for clinical content and revising article. Eddy Maher: Completing costing questionnaire, providing protocol details, sharing overall laboratory experience and drafting article. Jenny Taylor: Planning and facilitating work between centres. Drafting and revising article. Samantha JL Knight: Completing costing questionnaire, providing protocol details, other costing information, interpretation of data, providing information about learning disability and genome imbalance, drafting and revising article. Jenny Taylor and Samantha JL Knight contributed equally to the work presented.     

Cardiorespiratory fitness, different measures of adiposity, and cancer mortality in men

Objective: The purpose was to examine the prospective relationship among cardiorespiratory fitness level (CRF), different measures of adiposity, and cancer mortality in men. Research Methods and Procedures: Participants were 38,410 apparently healthy men who completed a comprehensive baseline health examination between 1970 and 2001. Clinical measures included BMI, waist circumference (WC), percent body fat, and CRF quantified as duration of a maximal treadmill exercise test. Participants were divided into fifths of CRF, BMI, WC, and percent body fat. Hazard ratios were computed with Cox regression analysis. Results: During a mean follow‐up period of 17.2 ± 7.9 years, 1037 cancer deaths occurred. Adjusted hazard ratios across incremental BMI quintiles were 1.0, 1.23, 1.15, 1.39, and 1.72; those of WC were 1.0, 1.05, 1.03, 1.31, and 1.64; those of percent body fat were 1.0, 1.24, 1.17, 1.23, and 1.50; and those of CRF were 1.0, 0.70, 0.67, 0.70, and 0.49 (trend p < 0.01 for each). Further adjustment for CRF eliminated the significant trend in mortality risk across percent body fat groups and attenuated the trend in risk across BMI and WC groups. Adjustment of CRF for adiposity measures had little effect on mortality risk. When grouped into categories of fit and unfit (upper 80% and lower 20% of CRF distribution, respectively), mortality rates (per 10,000 man‐years) were significantly lower in fit compared with unfit men within each stratum of BMI, WC, and percent body fat. Discussion: Higher levels of CRF are associated with lower cancer mortality risk in men, independently of several adiposity measures.     

Genetic mapping of a new set of microsatellite markers in a reference common bean (Phaseolus vulgaris) population BAT93 x Jalo EEP558

The present study describes a new set of 61 polymorphic microsatellite markers for beans and the construction of a genetic map using the BAT93 x Jalo EEP558 (BJ) population for the purpose of developing a reference linkage map for common bean (Phaseolus vulgaris). The main objectives were to integrate new microsatellites on the existing framework map of the BJ population, and to develop the first linkage map for the BJ population based exclusively on microsatellites. Of the total of 264 microsatellites evaluated for polymorphism, 42.8% showed polymorphism between the genitors. An integrated map was created totaling 199 mapped markers in 13 linkage groups, with an observed length of 1358 cM and a mean distance between markers of 7.23 cM. For the map constructed exclusively with microsatellites, 106 markers were placed in 12 groups with a total length of 606.8 cM and average distance of 6.8 cM. Linkage group designation and marker order for BM microsatellites generally agreed with previous mapping, while the new microsatellites were well distributed across the genome, corroborating the utility of the BJ population for a reference map. The extensive use of the microsatellites and the availability of a reference map can help in the development of other genetic maps for common bean through the transfer of information of marker order and linkage, which will allow comparative analysis and map integration, especially for future quantitative trait loci and association mapping studies.     

The F-box protein SKP2 binds to the phosphorylated threonine 380 in cyclin E and regulates ubiquitin-dependent degradation of cyclin E

Cyclin E is required for S phase entry. The subsequent ubiquitin-dependent degradation of cyclin E contributes to an orderly progression of the S phase. It has been shown that phosphorylation of threonine 380 (Thr380) in cyclin E provides a signal for its ubiquitin-dependent proteolysis. We report that SKP2, an F-box protein and a substrate-targeting component of the SCF(SKP2) ubiquitin E3 ligase complex, mediates cyclin E degradation. In vitro, SKP2 specifically interacted with the cyclin E peptide containing the phosphorylated-Thr380 but not with a cognate nonphosphorylated peptide. In vivo, expression of SKP2 induced cyclin E polyubiquitination and degradation. Conversion of Thr380 into nonphosphorylatable amino acids caused significant resistance of cyclin E to SKP2. The presence of the CDK inhibitor p27(Kip1) also prevented the SKP2-dependent degradation of cyclin E. Our findings suggest that SKP2 regulates cyclin E stability, thus contributing to the control of S phase progression.