Relationship between maternal environment and DNA methylation patterns of estrogen receptor alpha in wild Eastern Bluebird (Sialia sialis) nestlings: a pilot study

There is mounting evidence that, across taxa, females breeding in competitive environments tend to allocate more testosterone to their offspring prenatally and these offspring typically have more aggressive and faster‐growing phenotypes. To date, no study has determined the mechanisms mediating this maternal effect's influence on offspring phenotype. However, levels of estrogen receptor alpha (ERα) gene expression are linked to differences in early growth and aggression; thus, maternal hormones may alter gene regulation, perhaps via DNA methylation, of ERα in offspring during prenatal development. We performed a pilot study to examine natural variation in testosterone allocation to offspring through egg yolks in wild Eastern Bluebirds (Sialia sialis) in varying breeding densities and percent DNA methylation of CG dinucleotides in the ERα promoter in offspring brain regions associated with growth and behavior. We hypothesized that breeding density would be positively correlated with yolk testosterone, and prenatal exposure to maternal‐derived yolk testosterone would be associated with greater offspring growth and decreased ERα promoter methylation. Yolk testosterone concentration was positively correlated with breeding density, nestling growth rate, and percent DNA methylation of one out of five investigated CpG sites (site 3) in the diencephalon ERα promoter, but none in the telencephalon (n = 10). Percent DNA methylation of diencephalon CpG site 3 was positively correlated with growth rate. These data suggest a possible role for epigenetics in mediating the effects of the maternal environment on offspring phenotype. Experimentally examining this mechanism with a larger sample size in future studies may help elucidate a prominent way in which animals respond to their environment. Further, by determining the mechanisms that mediate maternal effects, we can begin to understand the potential for the heritability of these mechanisms and the impact that maternal effects are capable of producing at an evolutionary scale.     

Isolation and Properties of Suppressor-Sensitive Mutants of Bacillus subtilis Bacteriophage SPO2

Suppressor-sensitive mutants of Bacillus subtilis phage SPO2 were isolated and classified into 18 cistrons. A linear genetic map was constructed. The genes controlling early functions of phage development were clustered near the CI gene which may produce phage repressor.     

Porin Associates with Tom22 to Regulate the Mitochondrial Protein Gate Assembly

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CNS proteomes in alcohol and drug abuse and dependence

Drugs of abuse, including alcohol, can induce dependency formation and/or brain damage in brain regions important for cognition. 'High-throughput' approaches, such as cDNA microarray and proteomics, allow the analysis of global expression profiles of genes and proteins. These technologies have recently been applied to human brain tissue from patients with psychiatric illnesses, including substance abuse/dependence and appropriate animal models to help understand the causes and secondary effects of these complex disorders. Although these types of studies have been limited in number and by proteomics techniques that are still in their infancy, several interesting hypotheses have been proposed. Focusing on CNS proteomics, we aim to review and update current knowledge in this rapidly advancing area.     

Interferon-γ Promotes Inflammation and Development of T-Cell Lymphoma in HTLV-1 bZIP Factor Transgenic Mice

Human T-cell leukemia virus type 1 (HTLV-1) is an etiological agent of several inflammatory diseases and a T-cell malignancy, adult T-cell leukemia (ATL). HTLV-1 bZIP factor (HBZ) is the only viral gene that is constitutively expressed in HTLV-1-infected cells, and it has multiple functions on T-cell signaling pathways. HBZ has important roles in HTLV-1-mediated pathogenesis, since HBZ transgenic (HBZ-Tg) mice develop systemic inflammation and T-cell lymphomas, which are similar phenotypes to HTLV-1-associated diseases. We showed previously that in HBZ-Tg mice, HBZ causes unstable Foxp3 expression, leading to an increase in regulatory T cells (Tregs) and the consequent induction of IFN-γ-producing cells, which in turn leads to the development of inflammation in the mice. In this study, we show that the severity of inflammation is correlated with the development of lymphomas in HBZ-Tg mice, suggesting that HBZ-mediated inflammation is closely linked to oncogenesis in CD4⁺ T cells. In addition, we found that IFN-γ-producing cells enhance HBZ-mediated inflammation, since knocking out IFN-γ significantly reduced the incidence of dermatitis as well as lymphoma. Recent studies show the critical roles of the intestinal microbiota in the development of Tregs in vivo. We found that even germ-free HBZ-Tg mice still had an increased number of Tregs and IFN-γ-producing cells, and developed dermatitis, indicating that an intrinsic activity of HBZ evokes aberrant T-cell differentiation and consequently causes inflammation. These results show that immunomodulation by HBZ is implicated in both inflammation and oncogenesis, and suggest a causal connection between HTLV-1-associated inflammation and ATL.     

Meteorona kishinouyei,a new family,genus and species (Cnidaria,Cubozoa, Chirodropida) from Japanese Waters

A new family, genus and species of cubozoan box jellyfish belonging to the order Chirodropida is reported from the eastern Japan. Meteorona kishinouyei gen. et sp. n. possesses the following unique morphological characters with respect to other known species in the Chirodropida: having one tentacle per scalpel-like unbranched pedalium and slightly raised unbranched gastric saccules. A comparative table of the primary diagnostic characters of genus and order in the Chirodropida is given. The order Chirodropida is redefined. The family Chiropsellidae is established. Discussion is provided on the implications for these findings on our current understanding of Cubozoan systematics.     

Alstiphyllanines I-O, ajmaline type alkaloids from Alstonia macrophylla showing vasorelaxant activity

Seven new ajmaline type alkaloids, alstiphyllanines I-O (1-7) were isolated from the leaves of Alstonia macrophylla together with six related alkaloids (8-13). Structures and stereochemistry of 1-7 were fully elucidated and characterized by 2D NMR analysis. A series of alstiphyllanines I-O (1-7) as well as the known ajmaline type alkaloids (8-13) showed that they relaxed phenylephrine (PE)-induced contractions against rat aortic ring. Among them, vincamedine (10) showed potent vasorelaxant activity, which may be mediated through inhibition of Ca(2+) influx through voltage-dependent Ca(2+) channels (VDCs) and/or receptor-operated Ca(2+) channels (ROCs) as well as partially mediated the NO release from endothelial cells. The presence of substituents at both N-1 and C-17 may be important to show vasorelaxation activity.     

Existence of two sexual races in the planarian species switching between asexual and sexual reproduction

In certain planarian species that are able to switch between asexual and sexual reproduction, determining whether a sexual has the ability to switch to the asexual state is problematic, which renders the definition of sexuals controversial. We experimentally show the existence of two sexual races, acquired and innate, in the planarian Dugesia ryukyuensis. Acquired sexuals used in this study were experimentally switched from asexuals. Inbreeding of acquired sexuals produced both innate sexuals and asexuals, but inbreeding of innate sexuals produced innate sexuals only and no asexuals. Acquired sexuals, but not innate sexuals, were forced to become asexuals by ablation and regeneration (asexual induction). This suggests that acquired sexuals somehow retain asexual potential, while innate sexuals do not. We also found that acquired sexuals have the potential to develop hyperplastic and supernumerary ovaries, while innate sexuals do not. In this regard, acquired sexuals were more prolific than innate sexuals. The differences between acquired and innate sexuals will provide a structure for examining the mechanism underlying asexual and sexual reproduction in planarians.     

Central <Emphasis Type="SmallCaps">l</Emphasis>-alanine reduces energy expenditure with a hypnotic effect under an acute stressful condition in neonatal chicks

Recently, we reported that intracerebroventricular (i.c.v.) injection of l-alanine attenuated the stress response under an acute stressful condition in chicks. However, no information of l-alanine was available for the influence on energy expenditure and changes in the posture under stressful conditions. The purpose of the present study was to clarify whether central l-alanine affects heat production (HP) of neonatal chicks, and whether HP is correlated with the behavior after isolation-induced stress. The i.c.v. injection of l-alanine (0.8 μmol) decreased oxygen consumption, carbon dioxide production and HP shortly after injection. Central l-alanine reduced the posture for active wakefulness, but increased the posture for sitting motionless with head drooped (sleeping posture). The present study demonstrates that central l-alanine decreases energy expenditure and causes a hypnotic effect in chicks exposed to an acute stressful condition.