Dynamics of multiple sexual signals in relation to climatic conditions

Question: Can trait-specific phenotypic plasticity in response to annual environmental variation lead to changes in the strength of sexual selection through the relative expression of sexual ornaments at the population level? Data description: We recorded breeding dates and the sizes of white forehead and wing patches of male collared flycatchers (Ficedula albicollis) from 1998 to 2005 in a nestboxbreeding population in the Pilis Mountains, Hungary. As environmental predictors, we used the North Atlantic Oscillation (NAO) index and local weather data, classified as direct or indirect effects relative to the moult of the given ornament. Search method: First, we used general linear mixed models to assess environmental effects on the within-individual changes and absolute yearly sizes of forehead and wing patches. We then used similar models to determine whether the relative sizes of the two plumage traits at the population level varied among years. Finally, we used multiple regressions to establish if the relative yearly expression of an ornament affected standardized sexual selection gradients on this ornament in the given year. Conclusions: Within-individual changes in forehead and wing patch size were predicted by the climate of their moulting season (winter and summer, respectively). There was also an indirect effect of previous winter climate on changes in wing patch size. Environmental effects on the absolute expression of ornaments at the population level followed the within-individual patterns. The relative population-level expression of forehead and wing patches fluctuated significantly among years. Sexual selection on a given ornament increased with its relative expression in that year

Study on the Lithiation Reaction of 3-Diisopropylcarbamoyl-N-pivaloylphenylethylamine

As a continuation of our earlier studies on the lithiation-based synthesis of 8-methoxy-, 8-fluoro- and 8-chloro-3,4-dihydroisoquinoline, a similar approach was investigated for the preparation of the 8-diisopropylcarbamoyl congener. The corresponding N-pivaloyl phenylethylamine key intermediate was prepared via four new bifunctional intermediates in high overall yield. Lithiation of this intermediate followed by quenching with dimethylformamide led to a mixture: beside the desired compound containing the formyl moiety in the common ortho position of the two aromatic substituents, the isomer formylated in the other ortho position of the carbamoyl moiety was surprisingly obtained as the major product. The crude mixture could finally be transformed under acidic conditions to the target compound, 8-diisopropylcarbamoyl-substituted 3,4-dihydroisoquinoline, albeit in a low yield

Topography Based Surface Analysis and Morphological Correlation at the Northern Plains of Mars

Topography based surface analysis and morphology correlation for the northern hemisphere of Mars – The topographic analysis of the Martian surface might help to understand basic geomorphological connections and improve our understanding in the surface features of the Earth too. In this work we correlated the statistical topographic parameters and the remote sensed image based appearance of various locations along a meridional stripe at the northern hemisphere of Mars. The topographic location of nearly horizontal plains suggests that the erosion and re-deposition was not effective enough to transport the sediments at the topographic lowerst point at 50 km distance scale. Great difference could be identified between the topographic height distribution pattern of different analyzed terrains, suggesting different variability and complexity in the range in surface feature types there. Terrains resembling the pediment-like structures also could be at the analyzed terrains on Mars, but their firm identification requires more detailed analysis. The statistical based topography analysis could give useful input for detailed surface research in geomorphology

Heat shock factor-1 intertwines insulin/IGF-1, TGF-beta and cGMP signaling to control development and aging.

ABSTRACT: BACKGROUND: Temperature affects virtually all cellular processes. A quick increase in temperature challenges the cells to undergo a heat shock response to maintain cellular homeostasis. Heat shock factor-1 (HSF-1) functions as a major player in this response as it activates the transcription of genes coding for molecular chaperones (also called heat shock proteins) that maintain structural integrity of proteins. However, the mechanisms by which HSF-1 adjusts fundamental cellular processes such as growth, proliferation, differentiation and aging to the ambient temperature remain largely unknown. RESULTS: We demonstrate here that in Caenorhabditis elegans HSF-1 represses the expression of daf-7 encoding a TGF-beta (transforming growth factor-beta) ligand, to induce young larvae to enter the dauer stage, a developmentally arrested, non-feeding, highly stress-resistant, long-lived larval form triggered by crowding and starvation. Under favorable conditions, HSF-1 is inhibited by crowding pheromone-sensitive guanylate cyclase/cGMP (cyclic guanosine monophosphate) and systemic nutrient-sensing insulin/IGF-1 (insulin-like growth factor-1) signaling; loss of HSF-1 activity allows DAF-7 to promote reproductive growth. Thus, HSF-1 interconnects the insulin/IGF-1, TGF-beta and cGMP neuroendocrine systems to control development and longevity in response to diverse environmental stimuli. Furthermore, HSF-1 upregulates another TGF-beta pathway-interacting gene, daf-9/cytochrome P450, thereby fine-tuning the decision between normal growth and dauer formation. CONCLUSION: Together, these results provide mechanistic insight into how temperature, nutrient availability and population density coordinately influence development, lifespan, behavior and stress response through HSF-1

Sex-specific regulation of aging in Caenorhabditis elegans

A fascinating aspect of sexual dimorphism in various animal species is that the two sexes differ substantially in lifespan. In humans, for example, women's life expectancy exceeds that of men by 3-7 years. Whether this trait can be attributed to dissimilar lifestyles or genetic (regulatory) factors remains to be elucidated. Herein, we demonstrate that in the nematode Caenorhabditis elegans, the significantly longer lifespan of hermaphrodites-which are essentially females capable of sperm production-over males is established by TRA-1, the terminal effector of the sex-determination pathway. This transcription factor directly controls the expression of daf-16/FOXO, which functions as a major target of insulin/IGF-1 signaling (IIS) and key modulator of aging across diverse animal phyla. TRA-1 extends hermaphrodite lifespan through promoting daf-16 activity. Furthermore, TRA-1 also influences reproductive growth in a DAF-16-dependent manner. Thus, the sex-determination machinery is an important regulator of IIS in this organism. These findings provide a mechanistic insight into how longevity and development are specified unequally in the two genders. As TRA-1 is orthologous to mammalian GLI (glioma-associated) proteins, a similar sex-specific mechanism may also operate in humans to determine lifespan. © 2018 The Anatomical Society and John Wiley & Sons Ltd

Egy összetett szignalizációs mechanizmus: a madárének lokális, regionális és evolúciós mintázatai = Bird song as a multiple functioning sexual signal: patterns on individual, population and regional levels

Tervezett vizsgálataink célja egy komplex, ivarilag szelekctált szignál, a madárének funkcionális kapcsolatrendszereinek felderítése volt. Különböző szinteken, egyedektől a poulációs szinten keresztül a fajok közötti kapcsolatokig vizsgáltuk a szignál információ tartalmát és annak szerepét az ivari kiválasztódás és a természetes szelekció folyamatában. Terepi vizsgálataink bizonyították, hogy az ének különböző paraméterei az egyedi minőség más és más komponensét (parazitáltság, kor, stressz-tolerancia, személyiség) jelzik. Kimutattuk továbbá az ének szerepét a hím-hím versengésben valamint a hölgyválasz mechanizmusában. Populációs szintű vizsgálatainkban szimpatrikusan és allopatrikusan élő légykapók énekszegregációját elemeztuk az együttélés időskáláját is figyelembe véve. Modern komparatív analízisekkel interspecifikus kapcsolatot tártunk fel az ének összetettsége és az agyméret közötti, míg heterospecifikus vokális mimikri evolúcióját is vizsgáltuk. A kutatás során egy általunk először alkalmazott repertoárméret-becslő módszer fejlesztését is folytattuk egy nemzetközi kooperáció keretén belül. Eredményeinket nemzetközileg elismert folyoíratokban publikáltiuk. | The aim of the planned research was to investigate the functional relationships of a complex, sexually selected trait, namely bird song. We studied the information content of the signal, and its roles in sexual and natural selection by focusing on three organizational levels, such as individuals, populations and species. Our field research with the collared flycatcher (Ficedula albicollis) proved that different characteristics of the song signal different aspects of male quality (parasite load, age, stress-tolerance and personality). We also found that the song plays role in male-male competition and female choice. Comparisons of sympatric and allopatric populations of flycatchers in Europe revealed evidence for the segregation of song depending on the duration of the evolutionary contact. By using modern comparative methods, we failed to demonstrate an interspecific relationship between bird song and speciation, but discovered that the complexity of songs is evolutionary related to brain dimorphism between sexes. We also demonstrated some evolutionary patterns in association with heterospecific vocal mimicry. During this research, we developed a new method for estimating repertoire size. Our results have been published in the leading journals of the field