50 research outputs found
Differences in the Number of Intrinsically Disordered Regions between Yeast Duplicated Proteins, and Their Relationship with Functional Divergence
BACKGROUND: Intrinsically disordered regions are enriched in short interaction motifs that play a critical role in many protein-protein interactions. Since new short interaction motifs may easily evolve, they have the potential to rapidly change protein interactions and cellular signaling. In this work we examined the dynamics of gain and loss of intrinsically disordered regions in duplicated proteins to inspect if changes after genome duplication can create functional divergence. For this purpose we used Saccharomyces cerevisiae and the outgroup species Lachancea kluyveri. PRINCIPAL FINDINGS: We find that genes duplicated as part of a genome duplication (ohnologs) are significantly more intrinsically disordered than singletons (p<2.2(e)-16, Wilcoxon), reflecting a preference for retaining intrinsically disordered proteins in duplicate. In addition, there have been marked changes in the extent of intrinsic disorder following duplication. A large number of duplicated genes have more intrinsic disorder than their L. kluyveri ortholog (29% for duplicates versus 25% for singletons) and an even greater number have less intrinsic disorder than the L. kluyveri ortholog (37% for duplicates versus 25% for singletons). Finally, we show that the number of physical interactions is significantly greater in the more intrinsically disordered ohnolog of a pair (pâ=â0.003, Wilcoxon). CONCLUSION: This work shows that intrinsic disorder gain and loss in a protein is a mechanism by which a genome can also diverge and innovate. The higher number of interactors for proteins that have gained intrinsic disorder compared with their duplicates may reflect the acquisition of new interaction partners or new functional roles
Adult zebrafish as a model organism for behavioural genetics
Recent research has demonstrated the suitability of adult zebrafish to model some aspects of complex behaviour. Studies of reward behaviour, learning and memory, aggression, anxiety and sleep strongly suggest that conserved regulatory processes underlie behaviour in zebrafish and mammals. The isolation and molecular analysis of zebrafish behavioural mutants is now starting, allowing the identification of novel behavioural control genes. As a result of this, studies of adult zebrafish are now helping to uncover the genetic pathways and neural circuits that control vertebrate behaviour
The Gaia-ESO Survey: Empirical determination of the precision of stellar radial velocities and projected rotation velocities
Context. The Gaia-ESO Survey (GES) is a large public spectroscopic survey at the European Southern Observatory Very Large Telescope.
Aims. A key aim is to provide precise radial velocities (RVs) and projected equatorial velocities (v sin i) for representative samples of Galactic stars, that will complement information obtained by the Gaia astrometry satellite.
Methods. We present an analysis to empirically quantify the size and distribution of uncertainties in RV and v sin i using spectra from repeated exposures of the same stars.
Results. We show that the uncertainties vary as simple scaling functions of signal-to-noise ratio (S/N) and v sin i, that the uncertainties become larger with increasing photospheric temperature, but that the dependence on stellar gravity, metallicity and age is weak. The underlying uncertainty distributions have extended tails that are better represented by Studentâs t-distributions than by normal distributions.
Conclusions. Parametrised results are provided, that enable estimates of the RV precision for almost all GES measurements, and estimates of the v sin i precision for stars in young clusters, as a function of S/N, v sin i and stellar temperature. The precision of individual high S/N GES RV measurements is 0.22-0.26 km/s, dependent on instrumental configuration
The Gaia-ESO Public Spectroscopic Survey: Motivation, implementation, GIRAFFE data processing, analysis, and final data products
The Gaia-ESO Public Spectroscopic Survey is an ambitious project designed to
obtain astrophysical parameters and elemental abundances for 100,000 stars,
including large representative samples of the stellar populations in the
Galaxy, and a well-defined sample of 60 (plus 20 archive) open clusters. We
provide internally consistent results calibrated on benchmark stars and star
clusters, extending across a very wide range of abundances and ages. This
provides a legacy data set of intrinsic value, and equally a large wide-ranging
dataset that is of value for homogenisation of other and future stellar surveys
and Gaia's astrophysical parameters. This article provides an overview of the
survey methodology, the scientific aims, and the implementation, including a
description of the data processing for the GIRAFFE spectra. A companion paper
(arXiv:2206.02901) introduces the survey results. Gaia-ESO aspires to quantify
both random and systematic contributions to measurement uncertainties. Thus all
available spectroscopic analysis techniques are utilised, each spectrum being
analysed by up to several different analysis pipelines, with considerable
effort being made to homogenise and calibrate the resulting parameters. We
describe here the sequence of activities up to delivery of processed data
products to the ESO Science Archive Facility for open use. The Gaia-ESO Survey
obtained 202,000 spectra of 115,000 stars using 340 allocated VLT nights
between December 2011 and January 2018 from GIRAFFE and UVES. The full
consistently reduced final data set of spectra was released through the ESO
Science Archive Facility in late 2020, with the full astrophysical parameters
sets following in 2022
The Gaia-ESO Survey: Target selection of open cluster stars & x22c6;
Context. The Gaia-ESO Survey (GES) is a public, high-resolution spectroscopic survey, conducted with the multi-object spectrograph Fibre Large Array Multi Element Spectrograph (FLAMES) on the Very Large Telescope (European Southern Observatory, ESO, Cerro Paranal, Chile) from December 2011 to January 2018. Gaia-ESO has targeted all the main stellar components of the Milky Way, including thin and thick disc, bulge, and halo. In particular, a large sample of open clusters has been observed, from very young ones, just out of the embedded phase, to very old ones.
Aims. The different kinds of clusters and stars targeted in them are useful to reach the main science goals of the open cluster part of GES, which are the study of the open cluster structure and dynamics, the use of open clusters to constrain and improve stellar evolution models, and the definition of Galactic disc properties (e.g., metallicity distribution).
Methods. The Gaia-ESO Survey is organised in 19 working groups (WGs), each one being responsible for a task. We describe here the work of three of them, one in charge of the selection of the targets within each cluster or association (WG4), one responsible for defining the most probable candidate member stars (WG1), and another one in charge of the preparation of the observations (WG6). As the entire GES has been conducted before the second Gaia data release, we could not make use of the Gaia astrometry to define cluster member candidates. We made use of public and private photometry to select the stars to be observed with FLAMES, once brought on a common astrometric system (the one defined by 2MASS). Candidate target selection was based on ground-based proper motions, radial velocities, and X-ray properties when appropriate, for example, and it was mostly used to define the position of the clustersâ evolutionary sequences in the colour-magnitude diagrams. Targets for GIRAFFE were then selected near the sequences in an unbiased way. We used known information on membership, when available, only for the few stars to be observed with UVES.
Results. We collected spectra for 62 confirmed clusters in the main observing campaign (and a few more clusters were taken from the ESO archive). Among them are very young clusters, where the main targets are pre-main sequence stars, clusters with very hot and massive stars currently on the main sequence, intermediate-age and old clusters where evolved stars are the main targets. Our strategy of making the selection of targets as inclusive and unbiased as possible and of observing a significant and representative fraction of all possible targets permitted us to collect the largest, most accurate, and most homogeneous spectroscopic data set on open star clusters ever achieved
The impact of work-related values and work control on the career satisfaction of female freelancers
Using the job demands-resources theory incorporating a job-crafting perspective to develop a set of hypotheses, this study contributes to the self-employment and freelancing literature by examining whether female freelancers use their agency to mobilize their personal resources (i.e. work-related values) to craft their work resources (i.e. workâcontrol indicators: work autonomy and time-spatial flexibility) to achieve more career satisfaction. Our structural partial least squares model (Nâ=â203) shows that the work-related value âintrinsically rewarding workâ prompts two motivational processes that affect career satisfaction: one running directly to âcareer satisfactionâ and one through âwork autonomyâ. Although the value âworkâlife balanceâ is positively associated with greater âtime-spatial flexibilityâ, this does not affect career satisfaction. Moreover, we find negative associations between the value âfinancial securityâ, on the one hand, and the two work resources, on the other hand. Hence, the value financial security is negatively related to work autonomy towards career satisfaction. We conclude that female freelancersâ multiple, oftentimes blended values compete with one another, implying that achieving meaningful work, workâlife balance and financial independence simultaneously is difficult in female freelancersâ careers. We discuss the studyâs implications for future research and advocate labourâmarket stakeholders (e.g. freelancers, freelancersâ networks, career coaches, temporary work agencies, unions, local and national governments, educational institutions and public and private organizations) to partner in developing value-based career strategies and policies that account for less linear career paths in increasingly flexible and individualized markets and truly support (female) workers developing portfolios that better match with their multiple work-related values on a long-term basis