drift Dotaz Zobrazit nápovědu
elektronický časopis
- Konspekt
- Lékařské vědy. Lékařství
- NLK Obory
- genetika, lékařská genetika
- genetika, lékařská genetika
- NLK Publikační typ
- elektronické časopisy
The extracellular subunit of the major histocompatibility complex MHCIIβ plays an important role in the recognition of pathogens and the initiation of the adaptive immune response of vertebrates. It is widely accepted that pathogen-mediated selection in combination with neutral micro-evolutionary forces (e.g. genetic drift) shape the diversity of MHCIIβ, but it has proved difficult to determine the relative effects of these forces. We evaluated the effect of genetic drift and balancing selection on MHCIIβ diversity in 12 small populations of Galápagos mockingbirds belonging to four different species, and one larger population of the Northern mockingbird from the continental USA. After genotyping MHCIIβ loci by high-throughput sequencing, we applied a correlational approach to explore the relationships between MHCIIβ diversity and population size by proxy of island size. As expected when drift predominates, we found a positive effect of population size on the number of MHCIIβ alleles present in a population. However, the number of MHCIIβ alleles per individual and number of supertypes were not correlated with population size. This discrepancy points to an interesting feature of MHCIIβ diversity dynamics: some levels of diversity might be shaped by genetic drift while others are independent and possibly maintained by balancing selection.
- MeSH
- genetická variace MeSH
- genetický drift * MeSH
- genotyp MeSH
- geny MHC třídy II * MeSH
- hustota populace MeSH
- ostrovy MeSH
- Passeriformes genetika MeSH
- populační genetika MeSH
- selekce (genetika) * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Ekvádor MeSH
- ostrovy MeSH
- Publikační typ
- abstrakt z konference MeSH
Phenotypic invariance-the outcome of purifying selection-is a hallmark of biological importance. However, invariant phenotypes might be controlled by diverged genetic systems in different species. Here, we explore how an important and invariant phenotype-the development of sexually differentiated individuals-is controlled in over two dozen species in the frog family Pipidae. We uncovered evidence in different species for 1) an ancestral W chromosome that is not found in many females and is found in some males, 2) independent losses and 3) autosomal segregation of this W chromosome, 4) changes in male versus female heterogamy, and 5) substantial variation among species in recombination suppression on sex chromosomes. We further provide evidence of, and evolutionary context for, the origins of at least seven distinct systems for regulating sex determination among three closely related genera. These systems are distinct in their genomic locations, evolutionary origins, and/or male versus female heterogamy. Our findings demonstrate that the developmental control of sexual differentiation changed via loss, sidelining, and empowerment of a mechanistically influential gene, and offer insights into novel factors that impinge on the diverse evolutionary fates of sex chromosomes.
- MeSH
- biologická evoluce MeSH
- fenotyp MeSH
- genetický drift MeSH
- molekulární evoluce MeSH
- Pipidae genetika fyziologie MeSH
- pohlavní chromozomy genetika MeSH
- procesy určující pohlaví MeSH
- rekombinace genetická MeSH
- selekce (genetika) MeSH
- sexuální diferenciace MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, U.S. Gov't, Non-P.H.S. MeSH
132 s.
Drift is a phenomenon that can occur in cognitive-behavioral supervision, where core components of supervision are omitted, avoided, or deprioritized. This narrative review explores the signs, reasons, and impact of supervisory drift at the experiential, cognitive, and emotional levels for both the supervisor and the supervisee. Additionally, the article presents potential solutions for preventing and addressing supervisory drift, such as staying on track, anticipating problems before they arise, adapting supervision to the supervisee's needs, using active supervision methods to understand drift better, engaging in Supervision of Supervision (SoS), and using alliance measures. Through the use of case vignettes, we illustrate the potential solutions. We aim to provide a comprehensive understanding of supervisory drift and offer practical strategies for its prevention and management.
- MeSH
- kognitivně behaviorální terapie * organizace a řízení MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
