Single Cell Gap Transflective Liquid Crystal Display with Slanted Reflector Above Transmissive Pixels

Single cell gap transflective liquid crystal display which provides that the backlight traverses the reflective pixel portion twice and thereby follows a path similar to that of the ambient light. A slant reflector is built on the path of the back light to reflect the transmitted light to the reflective portion so that the back light and ambient light follow similar paths

Genes and pathways affected by CAG-repeat RNA-based toxicity in Drosophila

Spinocerebellar ataxia type 3 is one of the polyglutamine (polyQ) diseases, which are caused by a CAG-repeat expansion within the coding region of the associated genes. The CAG repeat specifies glutamine, and the expanded polyQ domain mutation confers dominant toxicity on the protein. Traditionally, studies have focused on protein toxicity in polyQ disease mechanisms. Recent findings, however, demonstrate that the CAG-repeat RNA, which encodes the toxic polyQ protein, also contributes to the disease in Drosophila. To provide insights into the nature of the RNA toxicity, we extracted brain-enriched RNA from flies expressing a toxic CAG-repeat mRNA (CAG100) and a non-toxic interrupted CAA/G mRNA repeat (CAA/G105) for microarray analysis. This approach identified 160 genes that are differentially expressed specifically in CAG100 flies. Functional annotation clustering analysis revealed several broad ontologies enriched in the CAG100 gene list, including iron ion binding and nucleotide binding. Intriguingly, transcripts for the Hsp70 genes, a powerful suppressor of polyQ and other human neurodegenerative diseases, were also upregulated. We therefore tested and showed that upregulation of heat shock protein 70 mitigates CAG-repeat RNA toxicity. We then assessed whether other modifiers of the pathogenic, expanded Ataxin-3 polyQ protein could also modify the CAG-repeat RNA toxicity. This approach identified the co-chaperone Tpr2, the transcriptional regulator Dpld, and the RNA-binding protein Orb2 as modifiers of both polyQ protein toxicity and CAG-repeat RNA-based toxicity. These findings suggest an overlap in the mechanisms of RNA and protein-based toxicity, providing insights into the pathogenicity of the RNA in polyQ disease

Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition)

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. For example, a key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process versus those that measure fl ux through the autophagy pathway (i.e., the complete process including the amount and rate of cargo sequestered and degraded). In particular, a block in macroautophagy that results in autophagosome accumulation must be differentiated from stimuli that increase autophagic activity, defi ned as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (inmost higher eukaryotes and some protists such as Dictyostelium ) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the fi eld understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. It is worth emphasizing here that lysosomal digestion is a stage of autophagy and evaluating its competence is a crucial part of the evaluation of autophagic flux, or complete autophagy. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. Along these lines, because of the potential for pleiotropic effects due to blocking autophagy through genetic manipulation it is imperative to delete or knock down more than one autophagy-related gene. In addition, some individual Atg proteins, or groups of proteins, are involved in other cellular pathways so not all Atg proteins can be used as a specific marker for an autophagic process. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field

Molecular insight into mechanisms of CAG-repeat RNA toxicity in polyglutamine disease from Drosophila

Spinocerebellar ataxia type 3 is one of the polyglutamine (polyQ) diseases, which are caused by a CAG repeat expansion within the coding region of the associated genes. The CAG repeat specifies glutamine, and the expanded polyQ domain confers dominant toxicity on the protein. Recent findings demonstrate that the CAG-repeat RNA, which encodes the toxic polyQ protein, also contributes to the toxicity in Drosophila. In this dissertation, I took both genetic and genomic approaches to provide insight into the nature of the RNA toxicity. A Drosophila model of CAG-repeat RNA toxicity was established that was appropriate for genetic screens. This expressed the repeat ubiquitously in flies, and lead to climbing and wing posture deficits. These flies were sensitive to the level of the toxic CAG-repeat, and showed modification by Mbl, a known modifier of the repeat. Microarray analysis then identified 160 genes that differentially expressed specifically in flies expressing toxic CAG-repeat RNA. Functional annotation clustering analysis revealed several enriched classes, including iron ion binding and nucleotide binding. Further, expression changes of Hsp70 were identified by microarray analysis. We then tested and found that that modulation of Hsp70 levels in flies suppressed the CAG-repeat RNA toxicity. Hsp70 is a powerful modulator of the pathogenic polyQ protein and therefore these findings suggested a potential overlap with polyQ protein modifiers. Known pathogenic polyQ protein modifiers were then tested for effects on the RNA toxicity. Besides Hsp70, the co-chaperone Tpr2, the transcriptional regulator Dpld, and the RNA-binding protein Orb2 were also identified as modifiers of the CAG-repeat RNA toxicity in this dissertation. These results highlight an overlap in mechanisms between RNA and protein-based toxicity, and provide a foundation for future work on the molecular pathogenicity of the RNA in disease

Applications Of Multidirectional Asymmetrical Microlens-Array Light-Control Films On Reflective Liquid-Crystal Displays For Image Quality Enhancement

The multidirectional asymmetrical microlens-array light-control film (MAMA-LCF) is developed for enhancing the image brightness and contrast ratio of various reflective liquid-crystal displays. By use of index-matching material, the interface reflection is greatly reduced. Through optimized designs, the surface-scattering effect is also suppressed; thus the contrast ratio is much enhanced. From experimental results, the MAMA-LCF leads to a ∼1.5× gain in brightness over the MgO standard white and a 15:1 contrast ratio for the reflective color super-twist nematic liquid-crystal display, 2.8× MgO and a 23:1 contrast ratio for the polymer-dispersed liquid-crystal, and 2.8× MgO and a 13:1 contrast ratio for the cholesteric liquid-crystal display. Potential applications of this low-cost plastic thin film for reflective liquid-crystal displays are foreseeable. © 2004 Optical Society of America

Defining Genetic Factors That Modulate Intergenerational CAG Repeat Instability in Drosophila melanogaster

Trinucleotide repeat instability underlies >20 human hereditary disorders. These diseases include many neurological and neurodegenerative situations, such as those caused by pathogenic polyglutamine (polyQ) domains encoded by expanded CAG repeats. Although mechanisms of instability have been intensely studied, our knowledge remains limited in part due to the lack of unbiased genome-wide screens in multicellular eukaryotes. Drosophila melanogaster displays triplet repeat instability with features that recapitulate repeat instability seen in patients with disease. Here we report an enhanced fly model with substantial instability based on a noncoding 270 CAG (UAS–CAG270) repeat construct under control of a germline-specific promoter. We find that expression of pathogenic polyQ protein modulates repeat instability of CAG270 in trans, indicating that pathogenic-length polyQ proteins may globally modulate repeat instability in the genome in vivo. We further performed an unbiased genetic screen for novel modifiers of instability. These studies indicate that different aspects of repeat instability are under independent genetic control, and identify CG15262, a protein with a NOT2/3/5 conserved domain, as a modifier of CAG repeat instability in vivo