The Sound and the Fury—Bees Hiss when Expecting Danger

Honey bees are important model systems for the investigation of learning and memory and for a better understanding of the neuronal basics of brain function. Honey bees also possess a rich repertoire of tones and sounds, from queen piping and quacking to worker hissing and buzzing. In this study, we tested whether the worker bees’ sounds can be used as a measure of learning. We therefore conditioned honey bees aversively to odours in a walking arena and recorded both their sound production and their movement. Bees were presented with two odours, one of which was paired with an electric shock. Initially, the bees did not produce any sound upon odour presentation, but responded to the electric shock with a strong hissing response. After learning, many bees hissed at the presentation of the learned odour, while fewer bees hissed upon presentation of another odour. We also found that hissing and movement away from the conditioned odour are independent behaviours that can co-occur but do not necessarily do so. Our data suggest that hissing can be used as a readout for learning after olfactory conditioning, but that there are large individual differences between bees concerning their hissing reaction. The basis for this variability and the possible ecological relevance of the bees’ hissing remain to be investigated.     

Identification of phytochrome B amino acid residues mutated in three new phyB mutants of Arabidopsis thaliana

The growth and development of plants is regulated by light viathe action of photoreceptors which are responsive to the red/far-red,blue and UV regions of the spectrum. Phytochrome B (the apoproteinof which is encoded by the PHYB gene) is one of the red/far-redabsorbing photoreceptors active in this process. In this paper,the isolation and characterization of three new EMS-inducedmutations of Arabidopsis which confer phytochrome B deficiencyare described. Complementation analysis showed that these mutations(phyB-101, phyB-102 and phyB-104) were allelic with PHYB. DNAsequence analysis showed that all three mutants contain nucleotidesubstitutions in the PHYB-101 gene sequence. phyB-101 carriesa nucleotide substitution within the second exon of the PHYBgene. This G-to-A substitution is a missense mutation that convertsa glutamate residue at position 812 of the phytochrome B apoproteinto a lysine residue. phyB-102, another missense mutant, carriesa C-to-T substitution which converts a serine residue at position349 of the phytochrome B apoprotein to a phenylalanine residue.phyB-104 carries a premature stop codon as a result of a G-to-Amutation 1190 bp down-stream of the ATG start codon of the PHYBsequence. The missense mutations in phyB-101 and phyB-102 causesignificant alterations in the predicted second ary structureof their respective mutant polypeptides, and identify aminoacid residues playing crucial roles in phytochrome B function,assembly or stability. Key words: Arabidopsis thaliana, phytochromet, phyB mutants, missense mutations     

Structure of the theta subunit of Escherichia coli DNA polymerase III in complex with the epsilon subunit

The catalytic core of Escherichia coli DNA polymerase III contains three tightly associated subunits, the alpha, epsilon, and theta subunits. The theta subunit is the smallest and least understood subunit. The three-dimensional structure of theta in a complex with the unlabeled N-terminal domain of the epsilon subunit, epsilon186, was determined by multidimensional nuclear magnetic resonance spectroscopy. The structure was refined using pseudocontact shifts that resulted from inserting a lanthanide ion (Dy3+, Er3+, or Ho3+) at the active site of epsilon186. The structure determination revealed a three-helix bundle fold that is similar to the solution structures of theta in a methanol-water buffer and of the bacteriophage P1 homolog, HOT, in aqueous buffer. Conserved nuclear Overhauser enhancement (NOE) patterns obtained for free and complexed theta show that most of the structure changes little upon complex formation. Discrepancies with respect to a previously published structure of free theta (Keniry et al., Protein Sci. 9:721-733, 2000) were attributed to errors in the latter structure. The present structure satisfies the pseudocontact shifts better than either the structure of theta in methanol-water buffer or the structure of HOT. satisfies these shifts. The epitope of epsilon186 on theta was mapped by NOE difference spectroscopy and was found to involve helix 1 and the C-terminal part of helix 3. The pseudocontact shifts indicated that the helices of theta are located about 15 A or farther from the lanthanide ion in the active site of epsilon186, in agreement with the extensive biochemical data for the theta-epsilon system.     

Mortality in adult intensive care patients with severe systemic inflammatory response syndromes is strongly associated with the hypo-immune TNF −238A polymorphism

The systemic inflammatory response syndrome (SIRS) is associated with activation of innate immunity. We studied the association between mortality and measures of disease severity in the intensive care unit (ICU) and functional polymorphisms in genes coding for Toll-like receptor 4 (TLR4), macrophage migratory inhibitory factor (MIF), tumour necrosis factor (TNF) and lymphotoxin-alpha (LTA). Two hundred thirty-three patients with severe SIRS were recruited from one general adult ICU in a tertiary centre in the UK. DNA from patients underwent genotyping by 5′ nuclease assay. Genotype was compared to phenotype. Primary outcome was mortality in ICU. Minor allele frequencies were TLR4 +896G 7%, MIF 173C 16%, TNF ?238A 10% and LTA +252G 34%. The frequency of the hypoimmune minor allele TNF ?238A was significantly higher in patients who died in ICU compared to those who survived (p?=?0.0063) as was the frequency of the two haplotypes LTA +252G, TNF ?1031T, TNF ?308G, TNF ?238A and LTA +252G, TNF?1031T, TNF?308A and TNF?238A (p?=?0.0120 and 0.0098, respectively). These findings re-enforce the view that a balanced inflammatory/anti-inflammatory response is the most important determinant of outcome in sepsis. Genotypes that either favour inflammation or its counter-regulatory anti-inflammatory response are likely to influence mortality and morbidity.     

Identification of a disruptor of the MDM2-p53 protein–protein interaction facilitated by high-throughput in silico docking

NSC 333003 has been identified from the NCI Diversity Set as an inhibitor of the MDM2-p53 protein–protein interaction by in silico docking (virtual screening). Its potency and chemical characteristics render it well suited for lead optimization studies that can result in more potent analogs with improved drug-like properties. Its synthesis was achieved using an acid catalyzed condensation reaction from commercially available benzothiazole hydrazine and pyridyl phenyl ketone in refluxing methanol. Stereochemical implications for this compound are described.     

Sex Recognition via Chemical Cues in the Sex-Role-Reversed Gulf Pipefish (Syngnathus scovelli)

Sexual selection theory predicts that members of the choosy sex, usually females, should employ multiple sensory systems to obtain information about potential mates. Such predictions should also apply to systems in which sexual selection acts most strongly on females (i.e. sex-role-reversed species), and males of these taxa should be the individuals employing multiple cues to assess female attractiveness. Very little work has been directed toward mate choice involving multiple sensory systems in sex-role-reversed taxa, but fishes of the family Syngnathidae (pipefishes, seahorses, and sea dragons) provide an excellent opportunity to contribute to this research enterprise. While much is known about visual communication in pipefish, the role of chemical communication has not been investigated. Using dichotomous choice tests, we found that male, but not female, Gulf pipefish attended to chemical cues of opposite sex conspecifics. Given that males distinguished sex on the basis of chemical cues, we also tested whether males could assess female body size, an important trait with respect to mate choice in pipefish, on the basis of chemical cues alone. When given the choice between chemical cues produced by large vs. small females, males exhibited no preference. Our results suggest that male pipefish can use chemical cues to distinguish between males and females but not to differentiate females of different body size.     

Non‐adaptive phenotypic plasticity: the effects of terrestrial and aquatic herbicides on larval salamander morphology and swim speed

Phenotypic plasticity, although ubiquitous, may not always be advantageous. Non‐adaptive plasticity is likely to occur in response to novel environmental stress. Anthropogenic contaminants, such as herbicides, are novel stressors that are not present in the evolutionary history of most species. We investigated the pattern and consequences of phenotypic plasticity induced by four glyphosate‐based herbicides (two terrestrial and two aquatic) in larvae of the spotted salamander, Ambystoma maculatum, by determining (1) whether the herbicides induced different morphologies; (2) if different morphologies translated to differences in burst swim performance; and (3) how induced individuals performed relative to non‐induced controls. Different herbicide formulations led to the production of significantly different head and tail morphologies, and tail morphology correlated with fastest escape speed. However, escape speed did not vary among treatments. In addition, three out of four herbicide treatments experienced accelerated growth rates, in terms of the lateral size of tails, although the tail shapes were either similar to preliminary controls or intermediate between preliminary and final controls. These observations suggest that herbicide‐induced morphology is a case of non‐adaptive phenotypic plasticity, and that there is potentially a trade‐off between growth and development for larvae exposed to different formulations. Understanding the functional significance of induced phenotypes is important for determining their importance in shaping an organism's ecological interactions and evolutionary trajectories. Furthermore, under different conditions, the morphological changes that we observed in response to exposure to herbicides might affect salamander fitness and influence population dynamics.