The TALE Factors and Nuclear Factor Y Cooperate to Drive Transcription at Zygotic Genome Activation

The TALE factors, comprising the pbx and prep/meis gene families, are transcription factors (TFs) vital to the proper formation of anterior anatomical structures during embryonic development. Although best understood as essential cofactors for tissue-specific TFs such as the hox genes during segmentation, the TALE factors also form complexes with nuclear factor Y (NFY) in the early zygote. In zebrafish, Pbx4, Prep1, and NFY are maternally deposited and can access their DNA binding sites in compact chromatin. Our results suggest that TALE/NFY complexes have a unique role in early embryonic development which is distinct from each factor’s independent functions at later stages. To characterize these TALE/NFY complexes, we employed high-throughput transcriptomic and genomic techniques in zebrafish embryos. Using dominant negatives to disrupt the function of each factor, we find that they display similar, but not identical, loss-of-function phenotypes and co-regulate genes involved in transcription regulation and embryonic development. Independently, the TALE factors regulate homeobox genes and NFY governs cilia-related genes. ChIP-seq analysis at zygotic genome activation reveals that the TALE factors occupy DECA sites adjacent to CCAAT boxes near genes expressed early in development and involved with transcription regulation. Finally, DNA elements containing TALE and NFY binding sites drive reporter gene expression in transgenic zebrafish, and disruption of TALE/NFY binding via mutation or dominant negatives eliminates this expression. Taken together, this data suggests that the TALE factors and NFY cooperate to regulate a set of development and transcription control genes in early zygotic development but also have independent roles after gastrulation

Duration and exposure to virtual environments: Sickness curves during and across sessions

Although simulator sickness is known to increase with protracted exposure and to diminish with repeated sessions, limited systematic research has been performed in these areas. This study reviewed the few studies with sufficient information available to determine the effect-that exposure duration and repeated exposure have on motion sickness. This evaluation confirmed that longer exposures produce more symptoms and that total sickness subsides over repeated exposures. Additional evaluation was performed to investigate the precise form of this relationship and to determine whether the same form was generalizable across varied simulator environments. The results indicated that exposure duration and repeated exposures are significantly linearly related to sickness outcomes (duration being positively related and repetition negatively related to total sickness). This was true over diverse systems and large subject pools. This result verified the generalizability of-the relationships among sickness, exposure duration, and repeated exposures. Additional research is indicated to determine the optimal length of a single exposure and the optimal intersession interval to facilitate adaptation

TALE and NF-Y co-occupancy marks enhancers of developmental control genes during zygotic genome activation in zebrafish [preprint]

Animal embryogenesis is initiated by maternal factors, but zygotic genome activation (ZGA) shifts control to the embryo at early blastula stages. ZGA is thought to be mediated by specialized maternally deposited transcription factors (TFs), but here we demonstrate that NF-Y and TALE – TFs with known later roles in embryogenesis – co-occupy unique genomic elements at zebrafish ZGA. We show that these elements are selectively associated with early-expressed genes involved in transcriptional regulation and possess enhancer activity in vivo. In contrast, we find that elements individually occupied by either NF-Y or TALE are associated with genes acting later in development – such that NF-Y controls a cilia gene expression program while TALE TFs control expression of hox genes. We conclude that NF-Y and TALE have a shared role at ZGA, but separate roles later during development, demonstrating that combinations of known TFs can regulate subsets of key developmental genes at vertebrate ZGA

In Situ Analysis of RNAi Using Affymetrix' ViewRNA System

RNA interference (RNAi) is a powerful mechanism for gene silencing that holds great promise for therapeutic applications. To design a drug, scientists must find siRNA sequences capable of strong mRNA silencing and effective methods to deliver the siRNA to target tissues. In situ hybridization techniques enable the visualization of the effectiveness of siRNAs. This report demonstrates the visualization of RNAi mediated gene silencing by using a new, highly sensitive bDNA probe-based in situ hybridization assay known as ViewRNA. The ViewRNA System showed in both a qualitative and semi-quantitative manner the reduction of SOD1 mRNA after cells were transfected with siRNA targeting the gene

Future Scientists and Engineers Club - At - Worcester Technical High School

The "Future Scientists and Engineers Club" was continued at Worcester Technical High School to assist juniors at the school in learning more about the fields of science and engineering. This club ran simultaneously with clubs at the other four Worcester public high schools, but unlike those clubs, ran during the school day. This and the other four clubs were successful in different ways and should all be continued in school years to come

Computers And Telecommunications In The Year 2000 - Virtual Environments And Intelligent Transportation Systems

In this, the third of three sets of position papers for the CTG-CSTG co-sponsored symposium on Computers and Telecommunications in the Year 2000, the authors provide us with a description of the future in two relatively new areas - virtual reality and intelligent transportation systems. In the first of the two papers, Kay M. Stanney and Robert S. Kennedy describe the performance efficiency, health and safety, and social issues that virtual technology will have to resolve, if virtual environments are to become commercially viable. In the second paper, William Yurcik describes the planned components of smart cars and smart highways, as well as the barriers we currently face in deploying associated intelligent transportation systems

Design of a systematic methods improvement planning methodology: part I - a shift to a multiple criteria approach for productivity gains

There are a large number of methods analysis techniques available with numerous potential benefits. In order to determine which techniques to use it is important to consider the specific benefits associated with each improvement technique and the costs of using that technique. Multiple-criteria approaches can be used to assist methods analysts to determine which techniques to apply for the most cost effective improvements. Many multiple-criteria approaches have been developed to date; however, they have not been used to assist in selecting methods analysis techniques. A prioritization model based on an additive value function is recommended for use in this context. This model uses both quantitative and subjective assessments of various methods improvement criteria in order to provide a guide for managers to systematically pursue productivity improvements