Identification of Candidate Regulators of Embryonic Stem Cell Differentiation by Comparative Phosphoprotein Affinity Profiling

Embryonic stem cells are a unique cell population capable both of self-renewal and of differentiation into all tissues in the adult organism. Despite the central importance of these cells, little information is available regarding the intracellular signaling pathways that govern self-renewal or early steps in the differentiation program. Embryonic stem cell growth and differentiation correlates with kinase activities, but with the exception of the JAK/STAT3 pathway, the relevant substrates are unknown. To identify candidate phosphoproteins with potential relevance to embryonic stem cell differentiation, a systems biology approach was used. Proteins were purified using phosphoprotein affinity columns, then separated by two-dimensional gel electrophoresis, and detected by silver stain before being identified by tandem mass spectrometry. By comparing preparations from undifferentiated and differentiating mouse embryonic stem cells, a set of proteins was identified that exhibited altered post-translational modifications that correlated with differentiation state. Evidence for altered post-translational modification included altered gel mobility, altered recovery after affinity purification, and direct mass spectra evidence. Affymetrix microarray analysis indicated that gene expression levels of these same proteins had minimal variability over the same differentiation period. Bioinformatic annotations indicated that this set of proteins is enriched with chromatin remodeling, catabolic, and chaperone functions. This set of candidate phosphoprotein regulators of stem cell differentiation includes products of genes previously noted to be enriched in embryonic stem cells at the mRNA expression level as well as proteins not associated previously with stem cell differentiation status

Novel Pink Bollworm Resistance to the Bt Toxin Cry 1Ac: Effects on Mating, Oviposition, Larval Development and Survival

Bt cotton plants are genetically engineered to produce insecticidal toxins from the Bacillus thuringiensis (Bt) Berliner (Bacillales: Bacillaceae) bacterium and target key lepidopteran pests. In all previous strains of pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae) selected in the laboratory for resistance to insecticidal Cry1Ac toxin using an artificial diet containing the toxin, resistance to Cry1Ac and to Bt cotton is linked to three cadherin alleles (r1, r2, and r3). In contrast, the BG(4) pink bollworm strain was selected for resistance to Bt cotton by feeding larvae for four days in each of 42 generations on bolls of ‘NuCOTN33B®’ that expressed Cry1Ac toxin. After additional selection for eleven generations on Cry1Ac-incorporated diet, the susceptibility to Cry1Ac, fecundity, egg viability, and mating of this strain (Bt4R) was compared with the unselected Cry1Ac-susceptible parent strain. Some larvae of the Bt4R strain survived on diet containing ≥ 10 µg Cry1Ac per milliliter artificial diet, but none survived on transgenic cotton bolls. In contrast to strains selected exclusively on Cry1Ac diet, some survival of progeny of reciprocal moth crosses of Bt4R resistant and Bt-susceptible strains occurred on Cry1Ac-treated diet, suggesting differences in levels of dominance. The Bt4R resistant strain does not have the r1, r2, or r3 mutant cadherin genes as do all previous strains of pink bollworm selected on Cry1Ac-treated artificial diet. The combined results suggest a mechanism of resistance to Cry1Ac that is different from previously described cadherin mutations

Fitness Cost of Resistance to Bt Cotton Linked with Increased Gossypol Content in Pink Bollworm Larvae

Fitness costs of resistance to Bacillus thuringiensis (Bt) crops occur in the absence of Bt toxins, when individuals with resistance alleles are less fit than individuals without resistance alleles. As costs of Bt resistance are common, refuges of non-Bt host plants can delay resistance not only by providing susceptible individuals to mate with resistant individuals, but also by selecting against resistance. Because costs typically vary across host plants, refuges with host plants that magnify costs or make them less recessive could enhance resistance management. Limited understanding of the physiological mechanisms causing fitness costs, however, hampers attempts to increase costs. In several major cotton pests including pink bollworm (Pectinophora gossypiella), resistance to Cry1Ac cotton is associated with mutations altering cadherin proteins that bind this toxin in susceptible larvae. Here we report that the concentration of gossypol, a cotton defensive chemical, was higher in pink bollworm larvae with cadherin resistance alleles than in larvae lacking such alleles. Adding gossypol to the larval diet decreased larval weight and survival, and increased the fitness cost affecting larval growth, but not survival. Across cadherin genotypes, the cost affecting larval growth increased as the gossypol concentration of larvae increased. These results suggest that increased accumulation of plant defensive chemicals may contribute to fitness costs associated with resistance to Bt toxins

The Total Filmmaker: thinking of screenwriting, directing and editing as one role

As screenwriting continues to establish itself as a discrete discipline in academia, either in alignment with creative writing departments or film and media practice departments, there is a danger that such developments may entrench a distancing of the craft from the cinematic form itself and that such a distancing may ultimately reinforce the screenplay's propensity for dramaturgy and the dramatic, rather than the sensory and experiential of the cinematic. Closely related creative stages in telling cinematic stories include directing and editing and this article seeks to argue, with reference to personal screen practice, that screenwriting, directing and editing are, in fact, three variations of the same thing. The article proposes the notion of the Total Filmmaker who embraces all three aspects of the cinematic storyteller. If the ultimate aim is to create a narrative that fully utilises the unique properties of the cinematic form in telling a story, rather than being dominated by the theatricality of dramatically driven classical narratives. How might one explore the relationship between screenwriting, directing and editing? Can an integrated approach to creating the cinematic blueprint change the way we think of pedagogy and screenwriting

Cohomological tautness for Riemannian foliations

In this paper we present some new results on the tautness of Riemannian foliations in their historical context. The first part of the paper gives a short history of the problem. For a closed manifold, the tautness of a Riemannian foliation can be characterized cohomologically. We extend this cohomological characterization to a class of foliations which includes the foliated strata of any singular Riemannian foliation of a closed manifold

Modified differentials and basic cohomology for Riemannian foliations

We define a new version of the exterior derivative on the basic forms of a Riemannian foliation to obtain a new form of basic cohomology that satisfies Poincar\'e duality in the transversally orientable case. We use this twisted basic cohomology to show relationships between curvature, tautness, and vanishing of the basic Euler characteristic and basic signature.Comment: 20 pages, references added, minor corrections mad

Notes on a paper of Mess

These notes are a companion to the article "Lorentz spacetimes of constant curvature" by Geoffrey Mess, which was first written in 1990 but never published. Mess' paper will appear together with these notes in a forthcoming issue of Geometriae Dedicata.Comment: 26 page

The government policy related to sugar-sweetened beverages in Indonesia

-There are several options to enforce reduction in the use of sugary drinks such as strengthening regulations, taxation on the products and food labeling. Aims & Objectives: 1) Identify the policy in Indonesia that regulates the quantity and the use of sugar in a beverage product; 2) Describe the sugar content in sugar-sweetened beverages (SSB) and its impact on human health. Material & Methods: Literature search on sugar use and tax policies on SSB was conducted and 6 relevant documents were found. A total of 91 SSB products were selected systematically by randomly selecting 5 beverages per day for 20 days. Beverages chosen were certified Halal by Majelis Ulama Indonesia, having product labeling, and certified by BPOM. Results: Indonesia has no policy related to restriction of sugar use. The contribution of sugar to energy of SSB products is quite high (75.68%). SSB intake may increase the risk of obesity and non-communicable diseases. Conclusion: The absence of tax policy and rules for regulating the use of sugar in a product can cause an increase in sugar consumption per day. It could potentially lead to non-communicable diseases and could have enormous consequences in health financing. The government needs to create policies for preventing the widespread impact of sugar consumption. Advocacy efforts to encourage the establishment of SSB taxation should be done