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Present Evidence Indicating (present + evidence_indicating)

Distribution by Scientific Domains

Life Sciences	50%

Selected Abstracts

Isolation and partial purification of the Saccharomyces cerevisiae cytokinetic apparatus,

CYTOSKELETON, Issue 1 2010
Brian A. Young
Abstract Cytokinesis is the process by which a cell physically divides in two at the conclusion of a cell cycle. In animal and fungal cells, this process is mediated by a conserved set of proteins including actin, type II myosin, IQGAP proteins, F-BAR proteins, and the septins. To facilitate biochemical and ultrastructural analysis of cytokinesis, we have isolated and partially purified the Saccharomyces cerevisiae cytokinetic apparatus. The isolated apparatus contains all components of the actomyosin ring for which we tested,actin, myosin heavy and light chain, and IQGAP,as well as septins and the cytokinetic F-BAR protein, Hof1p. We also present evidence indicating that the actomyosin rings associated with isolated cytokinetic apparati may be contractile in vitro, and show preliminary electron microscopic imaging of the cytokinetic apparatus. This first successful isolation of the cytokinetic apparatus from a genetically tractable organism promises to make possible a deeper understanding of cytokinesis. © 2009 Wiley-Liss, Inc. [source]

The ups and downs of signalling between root and shoot

NEW PHYTOLOGIST, Issue 3 2000
Christine Beveridge
It is becoming increasingly apparent that the long-distance signalling associated with many developmental processes is complex and that novel hormone-like signals may play substantial roles. The past decades have seen several substances (e.g. brassinosteroids, systemin and other polypeptides, mevalonic and jasmonic acids, polyamines, oligosaccharides, flavonoids, and quinones) vie for a place among the classical plant hormones (e.g. Spaink, 1996). Recent microinjection and grafting studies have also shown that RNA may act as a long-distance signal (Jorgensen et al., 1998; Xoconostle-Cázares et al., 1999). In this issue, Hannah et al. describe long-distance signalling and the regulation of root,shoot partitioning in dwarf lethal or dosage-dependent lethal (DL) mutants of common bean (Shii et al., 1980, 1981), and present evidence indicating that substances in addition to classical plant hormones (e.g. cytokinins) may be involved. As in the report by Hannah et al., much of the evidence for roles of unidentified long-distance signals in the control of plant development is indirect. The possibility that a small number of long-distance signals might control a multitude of developmental processes arises through the potential for differences in tissue sensitivity, fluctuations in hormone levels and differences in the nature of responses of different tissues to the same hormone. Consequently, particular hormones may influence numerous processes seemingly simultaneously, yet independently. Even so, long-distance signalling is involved in processes as diverse as root,shoot balance, senescence, branching, flowering, nodulation, stress responses and nutrient uptake. Through comparison of even a few different developmental processes, progress can be made to reveal the true complexity of plant development. Using this approach it is also clear that many unknown signals may be involved. [source]

Tumour immunology, vaccination and escape strategies

INTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 3 2003
A. García-Lora
Summary Our increasing knowledge of the mechanisms by which tumour cells escape immune effector cells is helping to establish new approaches to therapeutic vaccination against tumour development. One of the escape mechanisms used by tumour cells is the generation of multiple variants with different HLA phenotypes. These MHC class I phenotypic alterations play a key role in the tumour,host scenario, as they are crucial molecules for antigen presentation to T cells and modulation of natural killer (NK) cell activity. This review presents evidence indicating that tumours develop sophisticated MHC phenotypes that allow them to escape immune surveillance. We evaluate the importance of these alterations in terms of the potential development of therapeutic approaches to immune vaccination. [source]

"So that's what that is": Examining the impact of analogy on consumers' knowledge development for really new products

PSYCHOLOGY & MARKETING, Issue 6 2002
Jennifer Gregan-Paxton
The ever-accelerating pace of technological change has heralded an increasing number of new product introductions involving products that defy classification within existing categories. With the advent of these so-called "really new products," new questions about the influence of prior knowledge on consumer learning emerge. Chief among these is whether and to what extent prior knowledge plays a role in the comprehension of such products. Applying analogical learning theory to address this question, this investigation presents evidence indicating that analogy provides an effective link to the structural knowledge needed for consumers to learn about truly novel innovations. Reflecting this, subjects who engaged in analogical processing of new product information were more focused in their processing than subjects who processed the same information in the absence of analogy. Moreover, there was evidence to suggest that analogical processing itself results in the generation of positive affect. © 2002 Wiley Periodicals, Inc. [source]