Responses of growth and phlorotannins in <Emphasis Type="Italic">Fucus vesiculosus</Emphasis> to nutrient enrichment and herbivory

Discharge from anthropogenic sources may modify both macroalgal growth patterns and resource allocation to carbon based secondary compounds, thereby affecting their susceptibility for herbivory. We tested the effect of eutrophication in terms of nutrient enhancement on growth and phlorotannin concentration of Fucus vesiculosus by conducting manipulative experiments in the field and mesocosms. In the field experiment we utilised fish farms as nutrient sources and in the mesocosm-experiment we manipulated ambient nutrient levels and occurrence of the herbivorous isopod Idotea baltica. Vicinity of a fish farm affected neither growth nor the phlorotannin concentration of Fucus but increased the amount of epiphytes growing on Fucus. Other organisms such as epiphytic filamentous algae and periphyton, which are more capable of quickly utilizing excess nutrients, may restrain the direct effects of nutrient enhancement on Fucus. In a manipulative mesocosm experiment, neither nutrient enrichment nor occurrence of herbivores affected phlorotannin concentration implying lack of induced defences, at least in terms of increasing phlorotannin concentration. Feeding of thallus decreased the growth rate of algae, but the number of reproductive organs, receptacles, was not affected by herbivory. The negative effect of herbivory on the amount of apical tips tended to be stronger under nutrient enriched conditions. We conclude that eutrophication processes, in terms of nutrient enrichment, does not have strong direct effect on growth or phlorotannin production of F. vesiculosus. However, there may be important indirect consequences. First, herbivory may be targeted more to apical parts of the thallus under eutrophicated conditions. Second, the result that Fucus growing close to nutrient sources were smaller than those in control areas may reflect differences in mortality schedules of algae between eutrophicated and control areas.     

Human dignity, bioethics, and human rights

The authors analyse and assess the Universal Draft Declaration on Bioethics and Human Rights published by UNESCO. They argue that the Draft has two main weaknesses. It unnecessarily confines the scope of bioethics to life sciences and their practical applications. And it fails to spell out the intended role of human dignity in international ethical regulation.     

MATERNAL ADJUSTMENT OF EGG SIZE ORGANIZES ALTERNATIVE ESCAPE BEHAVIORS,PROMOTING ADAPTIVE PHENOTYPIC INTEGRATION

Numerous integrated traits contribute to any aspect of organismal performance, but favorable trait combinations are difficult to maintain in the face of genetic recombination. We investigated the role of maternal effects in promoting integration of alternative reproductive strategies (～throat colors) with antipredator traits (escape behaviors and dorsal patterns) in the side‐blotched lizard (Uta stansburiana). Previously, we reported that maternally derived estradiol adaptively pairs dorsal patterns with progeny throat colors. Here we show adaptive maternal effects on escape behaviors within each throat color morph. Specifically, yellow‐throated females and all females mated to yellow‐throated sires lay larger eggs. Larger eggs produce stockier offspring, who remain stockier throughout life. Stockiness promotes evasive escape behaviors (e.g., reversals), which are adaptive in barred, yellow‐throated offspring. Orange‐throated females lay smaller eggs, producing leaner hatchlings who perform vertical escape behaviors (e.g., jumping). Vertical behaviors enhance survival in striped, orange‐throated progeny. Escape behavior was not heritable, but was organized by natural or experimental egg size variation. Maternal effects on adaptive phenotypic integration are likely common in polymorphic species, because recombination otherwise breaks apart beneficial trait combinations. Furthermore, our results provide insight into the role of body shape in organizing (and constraining) evolution of integrated reproductive and antipredator strategies.     

Lower conditioning leisure-time physical activity in young adults born preterm at very low birth weight

Background

Adults born preterm at very low birth weight (VLBW, <1500 g) have elevated levels of risk factors for cardiovascular diseases and type 2 diabetes. Preliminary observations suggest that this could partly be explained by lower rates of physical activity. The aim of this study was to assess physical activity in healthy young adults born preterm at very low birth weight compared with term-born controls.

Methodology/Principal Findings

We studied 94 unimpaired young adults, aged 21–29 years, born at VLBW and 101 age-, sex-, and birth hospital-matched term-born controls from one regional center in Southern Finland. The participants completed a validated 30-item 12-month physical activity questionnaire and the NEO-Personality Inventory based on the Big Five taxonomy, the most commonly used classification of personality traits. Yearly frequency, total time, total volume and energy expenditure of conditioning and non-conditioning leisure-time physical activity (LTPA) and commuting physical activity were compared between VLBW and term-born subjects. A subset of participants underwent dual-energy x-ray absorptiometry for body composition measurement. Data were analyzed by multiple linear regression. Compared with controls, VLBW participants had lower frequency [−38.5% (95% CI; −58.9, −7.7)], total time [−47.4% (95% CI; −71.2, −4.1)], total volume [−44.3% (95% CI; −65.8, −9.2)] and energy expenditure [−55.9% (95% CI; −78.6, −9.4)] of conditioning LTPA when adjusted for age, sex, body mass index, smoking, parental education and personality traits. Adjusting for lean body mass instead of body mass index attenuated the difference. There were no differences in non-conditioning LTPA or commuting physical activity.

Conclusions/Significance

Compared with term-born controls, unimpaired VLBW adults undertake less frequent LTPA with lower total time and volume of exercise resulting in lower energy expenditure. Differences in personality that exist between the VLBW and term-born groups do not seem to explain this association.     

Fouling mediates grazing: intertwining of resistances to multiple enemies in the brown alga Fucus vesiculosus

Macroalgae have to cope with multiple natural enemies, such as herbivores and epibionts. As these are harmful for the host, the host is expected to show resistance to them. Evolution of resistance is complicated by the interactions among the enemies and the genetic correlations among resistances to different enemies. Here, we explored genetic variation in resistance to epibiosis and herbivory in the brown alga Fucus vesiculosus, both under conditions where the enemies coexisted and where they were isolated. F. vesiculosus showed substantial genetic variation in the resistance to both epibiosis and grazing. Grazing pressure on the alga was generally lower in the presence than in the absence of epibiota. Furthermore, epibiosis modified the susceptibility of different algal genotypes to grazing. Resistances to epibiosis and grazing were independent when measured separately for both enemies but positively correlated when both these enemies coexisted. Thus, when the enemies coexisted, the fate of genotypes with respect to these enemies was intertwined. Genotypic correlation between phlorotannins, brown-algal phenolic secondary metabolites, and the amount of epibiota was negative, indicating that these compounds contribute to resistance to epibiosis. In addition, phlorotannins correlated also with the resistance to grazing, but this correlation disappeared when grazing occurred in the absence of epibiota. This indicates that the patterns of selection for the type of the resistance as well as for the resistance traits vary with the occurrence patterns of the enemies.     

Frequency and density-dependent selection on life-history strategies--a field experiment

Negative frequency-dependence, which favors rare genotypes, promotes the maintenance of genetic variability and is of interest as a potential explanation for genetic differentiation. Density-dependent selection may also promote cyclic changes in frequencies of genotypes. Here we show evidence for both density-dependent and negative frequency-dependent selection on opposite life-history tactics (low or high reproductive effort, RE) in the bank vole (Myodes glareolus). Density-dependent selection was evident among the females with low RE, which were especially favored in low densities. Instead, both negative frequency-dependent and density-dependent selection were shown in females with high RE, which were most successful when they were rare in high densities. Furthermore, selection at the individual level affected the frequencies of tactics at the population level, so that the frequency of the rare high RE tactic increased significantly at high densities. We hypothesize that these two selection mechanisms (density- and negative frequency-dependent selection) may promote genetic variability in cyclic mammal populations. Nevertheless, it remains to be determined whether the origin of genetic variance in life-history traits is causally related to density variation (e.g. population cycles).     

Structural insights into steroid hormone binding: the crystal structure of a recombinant anti-testosterone Fab fragment in free and testosterone-bound forms.

The monoclonal anti-testosterone antibody (3-C(4)F(5)) has a relatively high affinity (3 x 10(8) m(-1)) with an overall good specificity profile. However, the earlier characterized binding properties have shown that both the affinity and specificity of this antibody must be improved if it is intended for use in clinical immunoassays. In this paper, the crystal structures of the recombinant anti-testosterone (3-C(4)F(5)) Fab fragment have been determined in the testosterone-bound and free form at resolutions of 2.60 and 2.72 A, respectively. The high affinity binding of the (3-C(4)F(5)) Fab is mainly determined by shape complementarity between the protein and testosterone. Only one direct hydrogen bond is formed between the hydroxyl group of the testosterone D-ring and the main-chain oxygen of Gly100(J)H. The testosterone is deeply bound in a hydrophobic pocket, and the close shape complementarity is mainly formed by the third complementarity-determining regions (CDR) of the heavy and light chain. Comparison of the bound structure with the free structure indicates conformational changes in the protein upon testosterone binding. The conformational changes of the side chains of two residues Glu95H and Tyr99H in the CDR-H3 are particularly essential for the binding. Interesting similarities in the binding of different steroids were also observed upon comparison of the available structures of anti-steroid antibodies.     

Lysinuric Protein Intolerance (LPI) Gene Maps to the Long Arm of Chromosome 14

Lysinuric protein intolerance (LPI) is an autosomal recessive disease characterized by defective transport of cationic amino acids and by hyperammonemia. Linkage analysis in 20 Finnish LPI families assigned the LPI gene locus to the proximal long arm of chromosome 14. Recombinations placed the locus between framework markers D14S72 and MYH7, a 10-cM interval in which the markers D14S742, D14S50, D14S283, and TCRA showed no recombinations with the phenotype. The phenotype was in highly significant linkage disequilibrium with markers D14S50, D14S283, and TCRA. The strongest allelic association obtained with marker TCRA, resulting in a P(excess) value of .98, suggests that the LPI gene locus lies in close proximity to this marker, probably within a distance of < 100 kb.     

Maturational costs of reproduction due to clutch size and ontogenetic conflict as revealed in the invisible fraction

Reproduction is thought to entail costs, but assessing survival costs associated with maturation as organisms express reproductive genes for the first time is problematic because many will die prior to expressing a phenotype. We quantified selection acting on this invisible fraction by measuring selection on predicted breeding values for clutch size estimated from a multigenerational pedigree of side-blotched lizards in which clutch size was heritable (h2=0.25+/-0.04). The survival effects of predicted breeding values for clutch size during maturation, however, differed between males and females indicating ontogenetic conflict. Increased mortality during maturation was associated with lower predicted breeding values for clutch size for females, but higher predicted breeding values for males who do not produce a clutch. Genetic correlations between clutch size and male and female survival were consistent with calculated selection differentials. Experimental yolk removal did not affect progeny survival during maturation, indicating that selection on maturing progeny was not due to confounding yolk-volume maternal effects, and hormone manipulations confirmed clutch size as the target of viability selection during maturation. Such episodes of selection prior to phenotypic expression of the trait will have important consequences for the evolution of reproductive investment.     

Ectodysplasin,Edar and TNFRSF19 are expressed in complementary and overlapping patterns during mouse embryogenesis

Ectodysplasin (Eda), a member of the tumor necrosis factor (TNF) superfamily, and its receptor Edar are necessary components of ectodermal organ development. Analysis of their expression patterns and mutant phenotypes has shown that during mouse hair and tooth development they may be involved in signalling between separate epithelial compartments. Here we have analysed ectodysplasin and Edar expression in other embryonic mouse tissues, and show that Edar mRNA is confined to the epithelium. Ectodysplasin and Edar are expressed in separate epithelial compartments in the developing brain and the lacrimal gland. In the salivary gland ectodysplasin is expressed in the mesenchyme and Edar in the epithelium. This is the first indication of ectodysplasin-Edar signalling between the epithelium and the mesenchyme. We also studied the expression pattern of a related TNF receptor, TNFRSF19, and show that it is expressed in an overlapping domain with Edar in the tooth, mammary gland, whiskers, and limb bud suggesting a potentially redundant role.