A SQUAMOSA MADS-box gene involved in the regulation of anthocyanin accumulation in bilberry fruits

Anthocyanins are important health promoting phytochemicals that are abundant in many fleshy fruits. Bilberry (Vaccinium myrtillus L.) is one of the best sources of these compounds. Here we report on the expression pattern and functional analysis of a SQUAMOSA (SQUA) class MADS-box transcription factor, VmTDR4, associated with anthocyanin biosynthesis in bilberry. Levels of VmTDR4 expression were spatially and temporally linked with colour development and anthocyanin-related gene expression. Virus induced gene silencing (VIGS) was used to suppress VmTDR4 expression in bilberry resulting in substantial reduction in anthocyanin levels in fully ripe fruits. Chalcone synthase was used a positive control in the VIGS experiments. Additionally, in sectors of fruit tissue in which the expression of the VmTDR4 gene was silenced, the expression of R2R3 MYB family transcription factors related to the biosynthesis of flavonoids were also altered. We conclude that VmTDR4 plays an important role in the accumulation of anthocyanins during normal ripening in bilberry; probably through direct or indirect control of transcription factors belonging to the R2R3 MYB family

Measuring Five Dimensions of Religiosity Across Adolescence

This paper theorizes and tests a latent variable model of adolescent religiosity in which five dimensions of religiosity are interrelated: religious beliefs, religious exclusivity, external religiosity, private practice, and religious salience. Research often theorizes overlapping and independent influences of single items or dimensions of religiosity on outcomes such as adolescent sexual behavior, but rarely operationalizes the dimensions in a measurement model accounting for their associations with each other and across time. We use longitudinal structural equation modeling (SEM) with latent variables to analyze data from two waves of the National Study of Youth and Religion. We test our hypothesized measurement model as compared to four alternate measurement models and find that our proposed model maintains superior fit. We then discuss the associations between the five dimensions of religiosity we measure and how these change over time. Our findings suggest how future research might better operationalize multiple dimensions of religiosity in studies of the influence of religion in adolescence

US and European Household Debt and Credit Constraints

This paper uses micro data from four OECD countries (the United States, Spain, Italy, and the Netherlands), to assess the determinants of household debt holding and to investigate whether or not credit constraints are important for household debt holding. We extend the existing literature in important ways. First, we present comparative evidence for four countries at the micro level, where we rely on household panel data for two countries; we are thus able to control for unobserved heterogeneity via individual household effects and to track changes in household behaviour over time. Second, by making data across countries as comparable as possible, we can explore the importance of the differences in institutional settings for debt incidence, debt outstanding and credit constraints. We also explore the implications for debt holding from consumption models, including a numerically solved precautionary savings model. We find that inter-country differences are substantial and remain even after controlling for a host of observable characteristics. This points to institutional differences between the countries being important

Genetics and epigenetics of fruit development and ripening

Fruits come in a vast variety of forms with both dry and fleshy types being essential components of the human diet. Elegant studies on the dry fruits of Arabidopsis have identified a suite of transcription factors involved in their development and dehiscence. Recent discoveries in tomato have revealed a hitherto unsuspected regulatory network involved in the developmental regulation of ripening in these fleshy fruits. Intriguingly it has become apparent that tomato shares some elements of its regulatory network in common with those involved in fruit development in Arabidopsis. Furthermore epigenetic variation has been shown to influence tomato ripening. These discoveries are likely to have a major impact on strategies for crop improvement in fruit bearing species

A Naturally Occurring Epigenetic Mutation in a Gene Encoding an SBP-box Transcription Factor Inhibits Tomato Fruit Ripening

A major component in the regulatory network controlling fruit ripening is likely to be the gene at the tomato Colorless non-ripening (Cnr) locus1, 2. The Cnr mutation results in colorless fruits with a substantial loss of cell-to-cell adhesion. The nature of the mutation and the identity of the Cnr gene were previously unknown. Using positional cloning and virus-induced gene silencing, here we demonstrate that an SBP-box (SQUAMOSA promoter binding protein–like) gene resides at the Cnr locus. Furthermore, the Cnr phenotype results from a spontaneous epigenetic change in the SBP-box promoter. The discovery that Cnr is an epimutation was unexpected, as very few spontaneous epimutations have been described in plants3, 4. This study demonstrates that an SBP-box gene is critical for normal ripening and highlights the likely importance of epialleles in plant development and the generation of natural variation