Genotype by environment interactions for fitness in hybrid genotypes of Avena barbata

We examined genotype (G) by environment (E) interactions for fitness in mesic and xeric ecotypes of the self-fertilizing annual grass, Avena barbata and their recombinant inbred hybrid progeny. Fitness was assayed (1) in experimental water and nutrient treatments in the greenhouse and (2) in common gardens in each ecotype's native habitat. G x E interactions were significant in the greenhouse. Nevertheless, the same recombinant genotypes tended to have high fitness across all water and nutrient treatments. G x E interactions were less pronounced in the field, and were driven by the contrast between the uniformly low survivorship at the mesic site in 2004 and genetic variation in fitness at the other years/site combinations. Moreover, the mesic ecotype consistently outperformed the xeric in both field and greenhouse. Several of the recombinant genotypes outperformed the parents in the novel greenhouse treatments, but these genotypes did not outperform the mesic parent in field trials. Indeed, it is only in the comparison between field and greenhouse environments that there was a noticeable change in the identity of the most-fit genotype. The results provide evidence that hybridization can create genotypes that are better adapted to newer environments such as those imposed in our greenhouse experiments.     

Structure-based design and synthesis of novel macrocyclic pyrazolo[1,5-a] [1,3,5]triazine compounds as potent inhibitors of protein kinase CK2 and their anticancer activities

A series of macrocyclic derivatives has been designed and synthesized based on the X-ray co-crystal structures of pyrazolo[1,5-a] [1,3,5]triazines with corn CK2 (cCK2) protein. Bioassays demonstrated that these macrocyclic pyrazolo[1,5-a] [1,3,5]triazine compounds are potent CK2 inhibitors with K(i) around 1.0 nM and strongly inhibit cancer cell growth with IC(50) as low as approximately 100 nM.     

A Multistep Model for Paclitaxel-Induced Apoptosis in Human Breast Cancer Cell Lines

Despite extensive previous investigation, the events occurring between paclitaxel-induced mitotic arrest and the subsequent onset of apoptosis remain incompletely understood. In the present study, the sequential morphological and biochemical changes that occur after paclitaxel treatment were examined in MDA-MB-468 (p53 mutant) and MCF-7 (p53 wild-type) breast cancer cells. Flow cytometry indicated that paclitaxel induces tetraploidy that persists until the onset of apoptosis in both cell lines. Light and electron microscopy indicated that the cells transiently arrest in mitosis and then enter a multinucleated interphase state characterized by the absence of punctate staining for CENP-F, a G(2) marker, but the presence of cyclin E, a G(1) cyclin, and p21(waf1/cip1), a cyclin-dependent kinase inhibitor. Despite high p21(waf1/cip1) levels, paclitaxel-treated cells incorporated thymidine into DNA. Aphidicolin inhibited this DNA synthesis but not the subsequent onset of apoptosis. Conversely, the broad-spectrum caspase inhibitor benzyloxycarbonyl-val-ala-asp(OMe)-fluoromethylketone inhibited apoptosis and enhanced the number of multinucleated cells but did not facilitate generation of octaploid cells. These results are consistent with a multistep model in which breast cancer cells exposed to paclitaxel undergo an aberrant mitotic exit; proceed through a tetraploid, multinucleated G(1) state; initiate an aphidicolin-suppressible process of DNA repair; and subsequently undergo apoptosis.     

Behavioral responses of an infant gorilla to maternal separation in a captive social group of lowland gorillas (Gorilla gorilla gorilla)

The present report describes behavioral reactions of a 33-month-old female infant gorilla to maternal separation in a captive social group whose composition is similar to that of wild groups. The infant gorilla responded differently to two types of maternal separation. When she remained alone for a few hours, she cried repeatedly and moved restlessly, indicating protest. Upon reunion and also for a few days thereafter, an intensification of the mother-infant relationship occurred. On the other hand, when she was separated from her mother but remained with the other group members for nine days, she did not display any behaviors that could be characterized as protest, but rather showed clear behavioral depression. During the 9-day separation period, she hardly played with other group members but she developed affiliative relationships with the leading male. After the reunion from the 9-day separation, she spent as much time near her mother as before separation and played with other infants at a level similar to that before separation, while she sometimes displayed behavioral patterns demanding the maintenance of physical contact with her mother. The present findings are compared with other reports in great apes and human children.     

Multi-locus phylogeny of dolphins in the subfamily Lissodelphininae: character synergy improves phylogenetic resolution

Background  

Dolphins of the genus Lagenorhynchus are anti-tropically distributed in temperate to cool waters. Phylogenetic analyses of cytochrome b sequences have suggested that the genus is polyphyletic; however, many relationships were poorly resolved. In this study, we present a combined-analysis phylogenetic hypothesis for Lagenorhynchus and members of the subfamily Lissodelphininae, which is derived from two nuclear and two mitochondrial data sets and the addition of 34 individuals representing 9 species. In addition, we characterize with parsimony and Bayesian analyses the phylogenetic utility and interaction of characters with statistical measures, including the utility of highly consistent (non-homoplasious) characters as a conservative measure of phylogenetic robustness. We also explore the effects of removing sources of character conflict on phylogenetic resolution.     

Pleiotropic Effects of a Methyl Donor Diet in a Novel Animal Model

Folate and other methyl-donor pathway components are widely supplemented due to their ability to prevent prenatal neural tube defects. Several lines of evidence suggest that these supplements act through epigenetic mechanisms (e.g. altering DNA methylation). Primary among these are the experiments on the mouse viable yellow allele of the agouti locus (A^vy). In the A^vy allele, an Intracisternal A-particle retroelement has inserted into the genome adjacent to the agouti gene and is preferentially methylated. To further test these effects, we tested the same diet used in the A^vy studies on wild-derived Peromyscus maniculatus, a native North American rodent. We collected tissues from neonatal offspring whose parents were fed the high-methyl donor diet as well as controls. In addition, we assayed coat-color of a natural variant (wide-band agouti = A^Nb) that overexpresses agouti as a phenotypic biomarker. Our data indicate that these dietary components affected agouti protein production, despite the lack of a retroelement at this locus. Surprisingly, the methyl-donor diet was associated with defects (e.g. ovarian cysts, cataracts) and increased mortality. We also assessed the effects of the diet on behavior: We scored animals in open field and social interaction tests. We observed significant increases in female repetitive behaviors. Thus these data add to a growing number of studies that suggest that these ubiquitously added nutrients may be a human health concern.     

Small molecule inhibitors of anthrax edema factor

Anthrax is a highly lethal disease caused by the Gram-(+) bacteria Bacillus anthracis. Edema toxin (ET) is a major contributor to the pathogenesis of disease in humans exposed to B. anthracis. ET is a bipartite toxin composed of two proteins secreted by the vegetative bacteria, edema factor (EF) and protective antigen (PA). Our work towards identifying a small molecule inhibitor of anthrax edema factor is the subject of this letter. First we demonstrate that the small molecule probe 5′-Fluorosulfonylbenzoyl 5′-adenosine (FSBA) reacts irreversibly with EF and blocks enzymatic activity. We then show that the adenosine portion of FSBA can be replaced to provide more drug-like molecules which are up to 1000-fold more potent against EF relative to FSBA, display low cross reactivity when tested against a panel of kinases, and are nanomolar inhibitors of EF in a cell-based assay of cAMP production.     

Carolina Chickadee (Aves, Paridae, Poecile carolinensis) Vocalization Rates: Effects of Body Mass and Food Availability under Aviary Conditions

We evaluated the effect of body mass and several environmental factors on vocalization rates of Carolina chickadees ( Poecile carolinensis ) housed in an aviary. Two different nonsong vocalizations (tseet and chick-a-dee) and song (fee-bee fee-bay) were recorded. Food was delivered from a feeder and three different levels of food access were presented to each bird: 10, 40 and 55 min/d. Two scales of body mass were measured: 'dawn mass' and 'focal mass' (mass during a focal observation divided by dawn mass). Across all birds, there was a significant negative correlation between both nonsong vocalization rates and body mass (both dawn and focal mass) and the effect of mass on call rate was greatest for days when food was relatively abundant. Nonsong vocalizations were also given at higher rates when food was limited (10 min/d) than when food was more abundant (40 and 55 min/d). No changes in call rates with time of day were observed. Overall, song rates were substantially lower than nonsong rates. Unlike nonsong rates, song rates were highest in birds that had relatively high dawn mass. No significant correlation between song rates and focal mass was observed, and no significant correlation between song rates and time of day was observed. Finally, vocalizations from nonfocal birds had little effect on vocalization rates of focal birds. Our results suggest that nonsong communicative signals are more important for birds facing energetic stress, while song is more important for birds that are not energetically stressed.     

Lipid-enhanced pollen and lipid-reduced flour diets and their effect on the longevity of honey bees (Apis mellifera L.)

Abstract  As eucalypt pollens contain low concentrations of lipid, enhancing pollen diets with fatty acids was hypothesised to improve honey bee longevity. Different concentrations of linoleic and oleic acid added to eucalypt pollen were trialled in small cages containing approximately 1400 bees each. Bees fed diets of redgum ( Corymbia calophylla (Lindl.) Hill & Johnson, formerly Eucalyptus calophylla ) pollen had the lowest mortality of 22 diets tested for 6 weeks and had life spans (50%) greater than 42 days. Linoleic acid mixed with a redgum diet in concentrations >6% corresponded to life spans of 24–25 days. Bee longevity appeared to be more sensitive to oleic acid as life spans decreased to 15–21 days when diets had concentrations >2%. The life spans of bees fed soya bean flour were 26 days on low (0.6% lipid) fat, 19 days on defatted and 20 days on full-fat diets. Bees fed lupin flour had a life span of 23 days. Adding redgum pollen to lupin flour caused increased mortality, but addition of pollen to soya bean flour was beneficial. Thus, beekeepers who choose to utilise soya bean or lupin flours as protein substitutes to pollen will have bees with reduced longevity. Bees fed redgum pollen that had been dried, crushed, irradiated and hermetically stored in a cool room for several years had similar longevity to bees fed fresh-collected and frozen redgum pollen.