Visual Gaze Estimation by Joint Head and Eye Information

International audienc

Alternative splicing and nonsense-mediated decay regulate telomerase reverse transcriptase (TERT) expression during virus-induced lymphomagenesis in vivo

<p>Abstract</p> <p>Background</p> <p>Telomerase activation, a critical step in cell immortalization and oncogenesis, is partly regulated by alternative splicing. In this study, we aimed to use the Marek's disease virus (MDV) T-cell lymphoma model to evaluate TERT regulation by splicing during lymphomagenesis <it>in vivo</it>, from the start point to tumor establishment.</p> <p>Results</p> <p>We first screened cDNA libraries from the chicken MDV lymphoma-derived MSB-1 T- cell line, which we compared with B (DT40) and hepatocyte (LMH) cell lines. The chTERT splicing pattern was cell line-specific, despite similar high levels of telomerase activity. We identified 27 alternative transcripts of chicken TERT (chTERT). Five were in-frame alternative transcripts without <it>in vitro </it>telomerase activity in the presence of viral or chicken telomerase RNA (vTR or chTR), unlike the full-length transcript. Nineteen of the 22 transcripts with a premature termination codon (PTC) harbored a PTC more than 50 nucleotides upstream from the 3' splice junction, and were therefore predicted targets for nonsense-mediated decay (NMD). The major PTC-containing alternatively spliced form identified in MSB1 (ie10) was targeted to the NMD pathway, as demonstrated by UPF1 silencing. We then studied three splicing events separately, and the balance between in-frame alternative splice variants (d5f and d10f) plus the NMD target i10ec and constitutively spliced chTERT transcripts during lymphomagenesis induced by MDV indicated that basal telomerase activity in normal T cells was associated with a high proportion of in-frame non functional isoforms and a low proportion of constitutively spliced chTERT. Telomerase upregulation depended on an increase in active constitutively spliced chTERT levels and coincided with a switch in alternative splicing from an in-frame variant to NMD-targeted variants.</p> <p>Conclusions</p> <p>TERT regulation by splicing plays a key role in telomerase upregulation during lymphomagenesis, through the sophisticated control of constitutive and alternative splicing. Using the MDV T-cell lymphoma model, we identified a chTERT splice variant as a new NMD target.</p

Composite objects and dependency relationships in Engineering

This paper depicts two important relationships required for CAD/CAM applications. The first one is the composition relationship between a pair of objects (a set of objects related by the composition relationship is collectively called a composite object). The second one presents the semantics of Dependency between two objects. Within the Knowledge Based Systems like YAFOOL, LOOPS and ORION, the semantics of composition and dependency relationship suffers from a number of serious shortcomings. Our Knowledge Based System, SHOOD, will provide a rich semantics of composition and dependency relationship which mitigates these shortcomings in a consistent and convenient fashion. This work is a part of fully developed scheme for composite object and dependency relationship management. 1. Introduction There is a general agreement on the need for better methods to handle engineering data. In recent years, the object-oriented paradigm (Minsky [8]) has gained popularity in the engineering design..

Systems and Architectures for Multimedia Information Retrieval

In this paper, we provide a brief survey on multimedia information retrieval and we introduce some ideas investigated in the special issue. We hope that the contributions of this issue will stimulate the readers to tackle the current challenges and problems in this highly important research direction. Such contributions are the basis of tomorrow's multimedia information systems. Our aims are to clarify some notions raised by this new technology by reviewing its current capabilities and potential usefulness to users in various areas. The research and development issues cover a wide range of fields, many of which are shared with media processing, signal processing, database technologies, and data mining

An efficient indexing structure for multimedia data

In the last few years, the increase of online video has challenged research in the field of video information retrieval. Video search engines have become common on the Internet and require the use of powerful tools for fast access to data. However the representation of multimedia data as video shot or keyframe with visual features requires the use of a multidimensional space and indexing structures face the well known ``curse of dimensionality". In this paper, we propose a new indexing structure that combines a clustering algorithm using random projections and a recursive multidimensional indexing structure. In our experiments, we study the effeciency and the effectiveness of our indexing structure using visual features of video shots of TRECVID database. We compare our proposed structure with other state-of-the-art methods