Three MADS-box genes similar to APETALA1 and FRUITFULL from silver birch (Betula pendula)

Despite intensive research on genetic regulation of flower development there are still only a few studies on the early phases of this process in perennial plants like trees. The aim of this study has been to identify genes that regulate early stages of inflorescence development in silver birch ( Betula pendula Roth) and to follow the expression of these genes during development of the unisexual birch inflorescences. Here we describe the cloning and characterization of 3 cDNAs representing MADS-box genes designated BpMADS3, BpMADS4 and BpMADS5, all belonging to the AP1/SQUA group of plant MADS-box genes. According to RNA blot analysis, all 3 genes are active during the development of both male and female inflorescences. However, differences in patterns of expression suggest that they play different roles. BpMADS3 is most similar in sequence to AP1 and SQUA, but it seems to have the highest expression at late developmental stages. BpMADS4 is most similar in sequence to the Arabidopsis gene FRUITFULL , but is expressed, in addition to developing inflorescences, in shoots and roots. BpMADS5 is also similar to FRUITFULL; its expression seems to be inflorescence-specific and continues during fruit development. Ectopic expression of either BpMADS3, BpMADS4 or BpMADS5 with the CaMV 35S promoter in tobacco results in extremely early flowering. All of these birch genes seem to act early during the transition to reproductive phase and might be involved in the determination of the identity of the inflorescence or flower meristem. They could apparently be used to accelerate flowering in various plant species.     

First molecular evidence for the existence of distinct fish and snake adenoviruses

From adenovirus-like viruses originating from a fish and a snake species, a conserved part of the adenoviral DNA polymerase gene was PCR amplified, cloned and sequenced. Phylogenetic analysis showed that the snake adenovirus is closely related to the members of the proposed genus Atadenovirus, whereas the fish isolate seems to represent a separate cluster, likely a new genus.     

Probabilistic analysis of probe reliability in differential gene expression studies with short oligonucleotide arrays

Probe defects are a major source of noise in gene expression studies. While existing approaches detect noisy probes based on external information such as genomic alignments, we introduce and validate a targeted probabilistic method for analyzing probe reliability directly from expression data and independently of the noise source. This provides insights into the various sources of probe-level noise and gives tools to guide probe design.     

Learning to Eat Vegetables in Early Life: The Role of Timing,Age and Individual Eating Traits

Vegetable intake is generally low among children, who appear to be especially fussy during the pre-school years. Repeated exposure is known to enhance intake of a novel vegetable in early life but individual differences in response to familiarisation have emerged from recent studies. In order to understand the factors which predict different responses to repeated exposure, data from the same experiment conducted in three groups of children from three countries (n = 332) aged 4–38 m (18.9±9.9 m) were combined and modelled. During the intervention period each child was given between 5 and 10 exposures to a novel vegetable (artichoke puree) in one of three versions (basic, sweet or added energy). Intake of basic artichoke puree was measured both before and after the exposure period. Overall, younger children consumed more artichoke than older children. Four distinct patterns of eating behaviour during the exposure period were defined. Most children were “learners” (40%) who increased intake over time. 21% consumed more than 75% of what was offered each time and were labelled “plate-clearers”. 16% were considered “non-eaters” eating less than 10 g by the 5^th exposure and the remainder were classified as “others” (23%) since their pattern was highly variable. Age was a significant predictor of eating pattern, with older pre-school children more likely to be non-eaters. Plate-clearers had higher enjoyment of food and lower satiety responsiveness than non-eaters who scored highest on food fussiness. Children in the added energy condition showed the smallest change in intake over time, compared to those in the basic or sweetened artichoke condition. Clearly whilst repeated exposure familiarises children with a novel food, alternative strategies that focus on encouraging initial tastes of the target food might be needed for the fussier and older pre-school children.     

Fibroblast growth factor 8b causes progressive stromal and epithelial changes in the epididymis and degeneration of the seminiferous epithelium in the testis of transgenic mice

Transgenic (Tg) mice expressing human fibroblast growth factor 8b (FGF8-b) under the probasin promoter (Tg [Pbsn-FGF8] L2-L5Elo; hereafter referred to as FGF8-b-Tg) were shown to produce FGF8-b at high levels in the prostate and epididymis and at lower levels in the testis. The present study examined the effects of FGF8-b expression on the epididymis and testis. In old (age, >6 mo) FGF8-b-Tg mice, epididymides were frequently enlarged, with epithelial and stromal hypercellularity progressing upon aging to epithelial dysplasia and malignant transformation of stroma. In addition, oligospermia, dilatation of the duct, and inflammation were frequently observed in the epididymides. In association with the epididymal changes, some FGF8-b-Tg mice presented a degenerative seminiferous epithelium of the testis. Consistent with this observation, infertile males were found in two FGF8-b-Tg mouse lines. Masson trichrome staining and immunohistochemical analysis of smooth muscle actin, laminin, and androgen receptor revealed that changes in the epididymal stroma closely resembled those previously found in the prostates of the FGF8-b-Tg mice. Genes previously found to be upregulated in the prostate of FGF8-b-Tg mice, such as osteopontin (Spp1) connective tissue growth factor (Ctgf), apolipoprotein D (Apod), and FGF receptor 1c (Fgfr1-c), were also upregulated in the epididymides, suggesting that similar molecular mechanisms were active in both tissues. However, unlike in the prostate, the changes in the epididymal epithelium of the FGF8-b-Tg mice did not progress into invasive carcinoma. The results suggest that prolonged and enhanced FGF signaling induces dramatic changes in the epididymis and testis that lead to infertility in a portion of the FGF8-b-Tg males.     

Genetic variance and covariance patterns for body weight and energy balance characters in an advanced intercross population of mice

We estimated heritabilities and genetic correlations for a suite of 15 characters in five functional groups in an advanced intercross population of over 2000 mice derived from a cross of inbred lines selected for high and low heat loss. Heritabilities averaged 0.56 for three body weights, 0.23 for two energy balance characters, 0.48 for three bone characters, 0.35 for four measures of adiposity, and 0.27 for three organ weights, all of which were generally consistent in magnitude with estimates derived in previous studies. Genetic correlations varied from -0.65 to +0.98, and were higher within these functional groups than between groups. These correlations generally conformed to a priori expectations, being positive in sign for energy expenditure and consumption (+0.24) and negative in sign for energy expenditure and adiposity (-0.17). The genetic correlations of adiposity with body weight at 3, 6, and 12 weeks of age (-0.29, -0.22, -0.26) all were negative in sign but not statistically significant. The independence of body weight and adiposity suggests that this advanced intercross population is ideal for a comprehensive discovery of genes controlling regulation of mammalian adiposity that are distinct from those for body weight.     

Recycling of aluminum can in terms of Life Cycle Inventory (LCI)

Background, Aims and Scope  Life Cycle Assessment is a technique for evaluating the environmental performance of a given product by: identifying and quantifying the energy and raw materials used in its manufacturing process, as well as the emissions of pollutants to water, soil, and air inherent in this production, use and disposal, and evaluating the environmental impact associated with the use of energy and materials and the emissions of pollutants, thus identifying opportunities to improve the system in order to optimize the environmental performance of the product. CETEA (Packaging Technology Center) has conducted a Life Cycle Assessment — LCA study of aluminum can with emphasis in life cycle inventory, collecting data for the reference years 2000–2002. The goal of this paper is to present part of this complete study, focusing the influence of aluminium recycling rate on the Life Cycle Inventory (LCI) of aluminum beverage cans in Brazil. Methods  The adopted methodology was based on the recommendations of SETAC — Society of Environmental Toxicology and Chemistry and the ISO 14040 Standard, approved by the Sub-Committee 05 of the Environmental Administration Technical Committee, TC-207, from ISO — INTERNATIONAL ORGANIZATION FOR STANDARDIZATION [1,2]. Data storage and modeling were performed by employing the PIRA Environmental Management System — PEMS [3]. Results  Taking into account the impact categories adopted in this study, it has been shown that recycling helps to improve the aluminium can environmental profile measured as LCI data. Discussion  For the transformed aluminium products, the recycling rate affects the values of the environmental parameters inventoried, but not in the same proportion, since the contribution of other stages of the product system life cycle and the recycling process remain unchanged, including the yield of this process. In general, the recycling balance is always positive due to the importance of the stages that precede the packaging production and the problem of increasing the municipal waste volume. Conclusions  The advantages of the recycling are obviously concentrated on the inventoried parameters related to the primary aluminum production and to the package disposal. The verified benefits of the recycling increase with the recycling rate enhancement. However, the effects on the inventory do not have the same magnitude of the recycling rate. This happens due to the relative contributions of the other life cycle stages, such as the transportation and sheet or can production. In agreement with the presented results, it is possible to conclude that the aluminum can recycling reduces part of the consumption of natural resources and the emissions associated to the stages previous to the production of the packaging. The parameters specifically related to the stage of aluminum production suffer reduction directly proportional to the increase of the recycling rate. In this way, all of the efforts made to increase the recycling rate will have a positive contribution to the LCI of the aluminum can. Recommendations  It is worth pointing out that LCA studies are iterative and dynamic. The data can always be refined, substituted or complemented with updated information in order to improve the representativeness of the analyzed sector. Perspectives  From this study, the aluminum sector in Brazil is able to quantify the benefits of future actions for environmental improvement of the Brazilian aluminum industry, as well as to contribute technically to Environmental Labeling initiatives regarding aluminum products. ESS-Submission Editor: Alain Dubreuil (dubreuil@nrcan.gc.ca)     

Reproducibility-optimized test statistic for ranking genes in microarray studies

A principal goal of microarray studies is to identify the genes showing differential expression under distinct conditions. In such studies, the selection of an optimal test statistic is a crucial challenge, which depends on the type and amount of data under analysis. While previous studies on simulated or spike-in datasets do not provide practical guidance on how to choose the best method for a given real dataset, we introduce an enhanced reproducibility-optimization procedure, which enables the selection of a suitable gene- anking statistic directly from the data. In comparison with existing ranking methods, the reproducibilityoptimized statistic shows good performance consistently under various simulated conditions and on Affymetrix spike-in dataset. Further, the feasibility of the novel statistic is confirmed in a practical research setting using data from an in-house cDNA microarray study of asthma-related gene expression changes. These results suggest that the procedure facilitates the selection of an appropriate test statistic for a given dataset without relying on a priori assumptions, which may bias the findings and their interpretation. Moreover, the general reproducibilityoptimization procedure is not limited to detecting differential expression only but could be extended to a wide range of other applications as well.