As the post-MDG era approaches in 2016, reducing child undernutrition is gaining high priority on the international development agenda, both as a maker and marker of development. Revisiting Smith and ...Haddad (2000), we use data from 1970 to 2012 for 116 countries, finding that safe water access, sanitation, women’s education, gender equality, and the quantity and quality of food available in countries have been key drivers of past reductions in stunting. Income growth and governance played essential facilitating roles. Complementary to nutrition-specific and nutrition-sensitive programs and policies, accelerating reductions in undernutrition in the future will require increased investment in these priority areas.
Transposable elements (TEs) make up the majority of many plant genomes. Their transcription and transposition is controlled through siRNAs and epigenetic marks including DNA methylation. To dissect ...the interplay of siRNA-mediated regulation and TE evolution, and to examine how TE differences affect nearby gene expression, we investigated genome-wide differences in TEs, siRNAs, and gene expression among three Arabidopsis thaliana accessions. Both TE sequence polymorphisms and presence of linked TEs are positively correlated with intraspecific variation in gene expression. The expression of genes within 2 kb of conserved TEs is more stable than that of genes next to variant TEs harboring sequence polymorphisms. Polymorphism levels of TEs and closely linked adjacent genes are positively correlated as well. We also investigated the distribution of 24-nt-long siRNAs, which mediate TE repression. TEs targeted by uniquely mapping siRNAs are on average farther from coding genes, apparently because they more strongly suppress expression of adjacent genes. Furthermore, siRNAs, and especially uniquely mapping siRNAs, are enriched in TE regions missing in other accessions. Thus, targeting by uniquely mapping siRNAs appears to promote sequence deletions in TEs. Overall, our work indicates that siRNA-targeting of TEs may influence removal of sequences from the genome and hence evolution of gene expression in plants.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•A wide range of prior capacities mitigated the food security impact of the floods.•Building these capacities should be considered in future resilience programing.•Resilience research should be based ...on a comprehensive conceptual framework.•Effective programing considers the full spectrum of capacities for shock recovery.
Using data collected before and after the catastrophic flooding that took place in northern Bangladesh in 2014, this paper contributes to the growing evidence on the factors enhancing households’ resilience to shocks, or their “resilience capacities”. The analysis takes into account all three dimensions of resilience capacity—absorptive, adaptive, and transformative—as well as a broad range of specific capacities supporting them. In addition to disaster preparedness and mitigation, it finds suggestive evidence that the following capacities reduced the negative impact of the flooding on household food security: social capital, human capital, exposure to information, asset holdings, livelihood diversity, safety nets, access to markets and services, women’s empowerment, governance, and psycho-social capabilities such as aspirations and confidence to adapt. The paper highlights the importance of taking a comprehensive approach to understanding the determinants of resilience in future research, one that accounts for the full range of potential capacities. It also points to the value of taking a cross-sectoral, multi-intervention approach to on-the-ground resilience programing in Bangladesh and other developing-country areas that are increasingly vulnerable to climate shocks.
Summary
DNA methylation is antagonistically controlled by DNA methyltransferases and DNA demethylases. The level of DNA methylation controls plant gene expression on a global level. We have examined ...impacts of global changes in DNA methylation on the Arabidopsis immune system. A range of hypo‐methylated mutants displayed enhanced resistance to the biotrophic pathogen Hyaloperonospora arabidopsidis (Hpa), whereas two hyper‐methylated mutants were more susceptible to this pathogen. Subsequent characterization of the hypo‐methylated nrpe1 mutant, which is impaired in RNA‐directed DNA methylation, and the hyper‐methylated ros1 mutant, which is affected in DNA demethylation, revealed that their opposite resistance phenotypes are associated with changes in cell wall defence and salicylic acid (SA)‐dependent gene expression. Against infection by the necrotrophic pathogen Plectosphaerella cucumerina, nrpe1 showed enhanced susceptibility, which was associated with repressed sensitivity of jasmonic acid (JA)‐inducible gene expression. Conversely, ros1 displayed enhanced resistance to necrotrophic pathogens, which was not associated with increased responsiveness of JA‐inducible gene expression. Although nrpe1 and ros1 were unaffected in systemic acquired resistance to Hpa, they failed to develop transgenerational acquired resistance against this pathogen. Global transcriptome analysis of nrpe1 and ros1 at multiple time‐points after Hpa infection revealed that 49% of the pathogenesis‐related transcriptome is influenced by NRPE1‐ and ROS1‐controlled DNA methylation. Of the 166 defence‐related genes displaying augmented induction in nrpe1 and repressed induction in ros1, only 25 genes were associated with a nearby transposable element and NRPE1‐ and/or ROS1‐controlled DNA methylation. Accordingly, we propose that the majority of NRPE1‐ and ROS1‐dependent defence genes are regulated in trans by DNA methylation.
Significance Statement
DNA methylation has been implicated in defence priming, but it is not fully understood what types of plant immunity are influenced or to what extent DNA methylation is involved. We addressed these questions by comprehensive phenotypic and transcriptomic analysis of Arabidopsis mutants that are oppositely affected in DNA methylation. We show that DNA (de)methylation processes play critical roles in certain types of innate, and demonstrate acquired immunity and that DNA (de)methylation exerts a global influence on the responsiveness of the defence‐related transcriptome, predominantly via trans‐regulatory mechanisms.
People's knowledge about the arts shapes how they experience and engage with art. Since its introduction, the 10-item Aesthetic Fluency Scale has been widely used to measure self-reported art ...knowledge. Drawing from findings and researchers' experience since then, the present work develops and evaluates a Revised Aesthetic Fluency Scale using item response theory to broaden its scope (36 items) and refine its response scale. In a large sample (n = 2,089 English-speaking adults), Study 1 found strong evidence for unidimensionality, good item fit, and a difficulty level suitable for its targeted population; Study 2 (n = 392) provided initial evidence for score validity via relationships with art engagement, Openness to Experience, and aesthetic responsiveness; and Study 3 derived a brief, 10-item form for time-constrained projects. Taken together, the revised scales build upon lessons learned from the original and appear promising for the next generation of research.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Non-additive interactions between genomes have important implications, not only for practical applications such as breeding, but also for understanding evolution. In extreme cases, genes from ...different genomic backgrounds may be incompatible and compromise normal development or physiology. Of particular interest are non-additive interactions of alleles at the same locus. For example, overdominant behavior of alleles, with respect to plant fitness, has been proposed as an important component of hybrid vigor, while underdominance may lead to reproductive isolation. Despite their importance, only a few cases of genetic over- or underdominance affecting plant growth or fitness are understood at the level of individual genes. Moreover, the relationship between biochemical and fitness effects may be complex: genetic overdominance, that is, increased or novel activity of a gene may lead to evolutionary underdominance expressed as hybrid weakness. Here, we describe a non-additive interaction between alleles at the Arabidopsis thaliana OAK (OUTGROWTH-ASSOCIATED PROTEIN KINASE) gene. OAK alleles from two different accessions interact in F(1) hybrids to cause a variety of aberrant growth phenotypes that depend on a recently acquired promoter with a novel expression pattern. The OAK gene, which is located in a highly variable tandem array encoding closely related receptor-like kinases, is found in one third of A. thaliana accessions, but not in the reference accession Col-0. Besides recruitment of exons from nearby genes as promoter sequences, key events in OAK evolution include gene duplication and divergence of a potential ligand-binding domain. OAK kinase activity is required for the aberrant phenotypes, indicating it is not recognition of an aberrant protein, but rather a true gain of function, or overdominance for gene activity, that leads to this underdominance for fitness. Our work provides insights into how tandem arrays, which are particularly prone to frequent, complex rearrangements, can produce genetic novelty.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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