8. CORRESPONDENCE

This paper investigates, through experiments using surrogate predators, differences in intraspecific alarm calls between familiar and unfamiliar Bronze Mannikin Spermestes cucculatus groups. Four groups of mannikins were captured with mist nets from four areas in Durban (i.e. original groups) and randomly mixed (i.e. assorted groups). These groups were exposed to latex terrestrial snakes and mounted aerial raptors, and their alarm calls and predator response behaviours recorded. The Bronze Mannikins were able to discriminate between predators of different sizes, and increased their calling rate and decreased the end frequency of the alarm call in response to larger predators. This perhaps signalled increased threat, while simultaneously decreasing the conspicuousness of the flock. When the alarm call structure of the original and assorted groups in response to both raptors and snakes was compared, birds in original groups called more often, but paused longer between calls. Anti-predator behaviour differed in that assorted groups were less vigilant and aggressive toward the predators and panicked more frequently. In these groups, a failure to transfer the predation threat information might have caused the group to stop behaving cohesively and reliably. The manipulated experiments carried out in this study indicated that Bronze Mannikins were able to communicate predator size risk to conspecifics, but not as successfully to unfamiliar group members, showing that the investment, probability through altruistic payback, is greater in stable groups.     

A phylogenetic analysis of the megadiverse Chalcidoidea (Hymenoptera)

Chalcidoidea (Hymenoptera) is extremely diverse with an estimated 500 000 species. We present the first phylogenetic analysis of the superfamily based on both morphological and molecular data. A web‐based, systematics workbench mx was used to score 945 character states illustrated by 648 figures for 233 morphological characters for a total of 66 645 observations for 300 taxa. The matrix covers 22 chalcidoid families recognized herein and includes 268 genera within 78 of 83 subfamilies. Morphological data were analysed alone and in combination with molecular data from ribosomal 18S (2105 bp) and 28S D2–D5 expansion regions (1812 bp). Analyses were analysed alone and in combined datasets using implied‐weights parsimony and likelihood. Proposed changes in higher classification resulting from the analyses include: (i) recognition of Eriaporidae, revised status; (ii) recognition of Cynipencyrtidae, revised status; (iii) recognition of Azotidae, revised status; (iv) inclusion of Sycophaginae in Agaonidae, revised status; (v) reclassification of Aphelinidae to include Aphelininae, Calesinae, Coccophaginae, Eretmocerinae and Eriaphytinae; (vi) inclusion of Cratominae and Panstenoninae within Pteromalinae (Pteromalidae), new synonymy; (vii) inclusion of Epichrysomallinae in Pteromalidae, revised status. At a higher level, Chalcidoidea was monophyletic, with Mymaridae the sister group of Rotoitidae plus the remaining Chalcidoidea. A eulophid lineage was recovered that included Aphelinidae, Azotidae, Eulophidae, Signiphoridae, Tetracampidae and Trichogrammatidae. Eucharitidae and Perilampidae were monophyletic if Eutrichosomatinae (Pteromalidae) was included, and Eupelmidae was monophyletic if Oodera (Pteromalidae: Cleonyminae) was included. Likelihood recovered a clade of Eupelmidae + (Tanaostigmatidae + (Cynipencyrtus + Encyrtidae). Support for other lineages and their impact on the classification of Chalcidoidea is discussed. Several life‐history traits are mapped onto the new phylogeny.     

Lactobacillus casei Shirota protects from fructose-induced liver steatosis: A mouse model

To test the hypothesis that Lactobacillus casei Shirota (Lcs) protects against the onset of non-alcoholic fatty liver disease (NAFLD) in a mouse model of fructose-induced steatosis, C57BL/6J mice were either fed tap water or 30% fructose solution +/- Lcs for 8 weeks. Chronic consumption of 30% fructose solution led to a significant increase in hepatic steatosis as well as plasma alanine-aminotransferase (ALT) levels, which was attenuated by treatment with Lcs. Protein levels of the tight junction protein occludin were found to be markedly lower in both fructose treated groups in the duodenum, whereas microbiota composition in this part of the intestine was not affected. Lcs treatment markedly attenuated the activation of the Toll-like receptor (TLR) 4 signalling cascade found in the livers of mice only treated with fructose. Moreover, in livers of fructose fed mice treated with Lcs peroxisome proliferator-activated receptor (PPAR)-γ activity was markedly higher than in mice only fed fructose. Taken together, the results of the present study suggest that the dietary intake of Lcs protects against the onset of fructose-induced NAFLD through mechanisms involving an attenuation of the TLR-4-signalling cascade in the liver.     

Lre1 Directly Inhibits the NDR/Lats Kinase Cbk1 at the Cell Division Site in a Phosphorylation-Dependent Manner

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Substrate specificity and catalysis by the editing active site of Alanyl-tRNA synthetase from Escherichia coli

Aminoacyl-tRNA synthetases (ARSs) enhance the fidelity of protein synthesis through multiple mechanisms, including hydrolysis of the adenylate and cleavage of misacylated tRNA. Alanyl-tRNA synthetase (AlaRS) limits misacylation with glycine and serine by use of a dedicated editing domain, and a mutation in this activity has been genetically linked to a mouse model of a progressive neurodegenerative disease. Using the free-standing Pyrococcus horikoshii AlaX editing domain complexed with serine as a model and both Ser-tRNA(Ala) and Ala-tRNA(Ala) as substrates, the deacylation activities of the wild type and five different Escherichia coli AlaRS editing site substitution mutants were characterized. The wild-type AlaRS editing domain deacylated Ser-tRNA(Ala) with a k(cat)/K(M) of 6.6 × 10(5) M(-1) s(-1), equivalent to a rate enhancement of 6000 over the rate of enzyme-independent deacylation but only 12.2-fold greater than the rate with Ala-tRNA(Ala). While the E664A and T567G substitutions only minimally decreased k(cat)/K(M,) Q584H, I667E, and C666A AlaRS were more compromised in activity, with decreases in k(cat)/K(M) in the range of 6-, 6.6-, and 15-fold. C666A AlaRS was 1.7-fold more active on Ala-tRNA(Ala) relative to Ser-tRNA(Ala), providing the only example of a true reversal of substrate specificity and highlighting a potential role of the coordinated zinc in editing substrate specificity. Along with the potentially serious physiological consequences of serine misincorporation, the relatively modest specificity of the AlaRS editing domain may provide a rationale for the widespread phylogenetic distribution of AlaX free-standing editing domains, thereby contributing a further mechanism to lower concentrations of misacylated tRNA(Ala).     

Allochronic separation versus mate choice: nonrandom patterns of mating between fall armyworm host strains

Assortative mating may result from intrinsic individual mating preferences or from assortment traits not requiring expression of preferences. Assortment traits are phenotypes expressed in both sexes that enhance the probability of encountering individuals possessing similar trait values. In the noctuid moth Spodoptera frugiperda, it has been suggested that nonrandom mating between two host strains is caused by a temporal assortment trait-that is, differential timing of calling and copulation during the night. By experimental manipulation of this trait in controlled mate-choice experiments, we investigated whether mating by same-strain individuals is enhanced mainly by the allochronic shift of mating activity or is also affected by time-independent intrinsic mating preferences. The observed patterns suggest that nonrandom mating between the two host strains in the laboratory is shaped by an interaction of both effects that is dominated by mating preferences during the first encounter night. This interaction changes over time as the preferences become weaker on subsequent nights. Males were less restricted than females with regard to both the time shift in mating activity and mate preferences. Although the nature of the mate-preference mechanism remains elusive, its restriction to females suggests that male-produced close-range pheromones emitted during courtship play a role.     

Measurement of serum levels of natalizumab, an immunoglobulin G4 therapeutic monoclonal antibody

Chlorophyllide a is a metabolite late in the biosynthesis of chlorophylls and bacteriochlorophylls. Isolation procedures for chlorophyllide a from Rhodobacter capsulatus CB1200 and barley (Hordeum vulgare L.) are described and compared. R. capsulatus CB1200 is a double mutant in the bacteriochlorophyllide a biosynthetic pathway, and chlorophyllide a is excreted by the cells when grown in Tween 80-containing liquid medium. It was purified by liquid or solid phase extraction, yielding 7 mg of chlorophyllide a from 1 L of culture. In a second approach, intrinsic chlorophyllase activity was used to dephytylate chlorophyll in an acetonic preparation of leaves of wild-type or chlorophyll b-deficient barley. Purification was achieved by liquid phase extraction, yielding 14 μg of chlorophyllide a per gram of barley leaves. Chlorophyllide a was identified by thin layer chromatography, absorption spectroscopy, and mass spectrometry.