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Cellular Behaviour (cellular + behaviour)
Selected AbstractsLinking physiological mechanisms of coherent cellular behaviour with more general physical approaches towards the coherence of lifeIUBMB LIFE, Issue 11 2006Laurent Jaeken Abstract Schrödinger pointed out that one of the most fundamental properties of life is its coherent behaviour. This property has been approached from a physiological point of view by Ling in his 'association-induction hypothesis' and extended by Pollack (gel-sol theory), by Chaplin and by Kaivarainen (detailed studies of cellular water). The question of coherence has also been attacked from general physics in three independent approaches: from non-linear thermodynamics (Fröhlich), from quantum field theory (Del Giudice and his group) and from quantum mechanics (Davydov). In this paper all these approaches are unified. The emerging picture constitutes a new paradigm of life. iubmb Life, 58: 642 - 646, 2006 [source] CP27 affects viability, proliferation, attachment and gene expression in embryonic fibroblastsCELL PROLIFERATION, Issue 4 2002X. Luan CP27 is a gene that has been cloned from an E11 early embryonic library and has been suggested to mediate early organogenesis (Diekwisch et al., 1999, Gene 235, 19). We have hypothesized that CP27 exhibits its effects on organogenesis by affecting individual cell function. Based on the CP27 expression pattern we have selected the CP27 expressing embryonic fibroblast cell line BALB/c 3T3 to determine the effects of CP27 on cell function. CP27 loss of function strategies were performed by adding 5, 12.5 or 25 µg/ml anti-CP27 antibody to cultured BALB/c 3T3 cells and comparing the results to controls in which identical concentrations of rabbit serum were added to the culture medium. Other controls included an antibody against another extracellular matrix protein amelogenin (negative control) and anti-CP27 antibodies directed against other areas of the CP27 molecule (positive control). Following cell culture, cell viability, apoptosis, cell proliferation, cell shape, cellular attachment and fibronectin matrix production were assayed using MTT colourimetric assay, BrdU staining, morphometry, immunostaining and western blot analysis. Block of CP27 function using an antibody strategy resulted in the following significant changes: (i) reduced viability, (ii) increased number of apoptotic cells, (iii) reduced proliferation, (iv) alterations in cell shape, (v) loss of attachment, and (vi) reduction in fibronectin matrix production. There was also a redistribution in fibronectin matrix organization demonstrated by immunohistochemistry. We conclude that CP27 plays an important role in the maintance of normal cell function and that CP27 block leads to significant changes in cellular behaviour. [source] Myogenesis and molecules, insights from zebrafish Danio rerioJOURNAL OF FISH BIOLOGY, Issue 8 2009S.-W. Chong Myogenesis is a fundamental process governing the formation of muscle in multicellular organisms. Recent studies in zebrafish Danio rerio have described the molecular events occurring during embryonic morphogenesis and have thus greatly clarified this process, helping to distinguish between the events that give rise to fast v. slow muscle. Coupled with the well-known Hedgehog signalling cascade and a wide variety of cellular processes during early development, the continual research on D. rerio slow muscle precursors has provided novel insights into their cellular behaviours in this organism. Similarly, analyses on fast muscle precursors have provided knowledge of the behaviour of a sub-set of epitheloid cells residing in the anterior domain of somites. Additionally, the findings by various groups on the roles of several molecules in somitic myogenesis have been clarified in the past year. In this study, the authors briefly review the current trends in the field of research of D. rerio trunk myogenesis. [source] Genetic analysis of two phosphodiesterases reveals cyclic diguanylate regulation of virulence factors in Dickeya dadantiiMOLECULAR MICROBIOLOGY, Issue 3 2010Xuan Yi Summary Cyclic diguanylate (c-di-GMP) is a second messenger implicated in the regulation of various cellular properties in several bacterial species. However, its function in phytopathogenic bacteria is not yet understood. In this study we investigated a panel of GGDEF/EAL domain proteins which have the potential to regulate c-di-GMP levels in the phytopathogen Dickeya dadantii 3937. Two proteins, EcpB (contains GGDEF and EAL domains) and EcpC (contains an EAL domain) were shown to regulate multiple cellular behaviours and virulence gene expression. Deletion of ecpB and/or ecpC enhanced biofilm formation but repressed swimming/swarming motility. In addition, the ecpB and ecpC mutants displayed a significant reduction in pectate lyase production, a virulence factor of this bacterium. Gene expression analysis showed that deletion of ecpB and ecpC significantly reduced expression of the type III secretion system (T3SS) and its virulence effector proteins. Expression of the T3SS genes is regulated by HrpL and possibly RpoN, two alternative sigma factors. In vitro biochemical assays showed that EcpC has phosphodiesterase activity to hydrolyse c-di-GMP into linear pGpG. Most of the enterobacterial pathogens encode at least one T3SS, a major virulence factor which functions to subvert host defences. The current study broadens our understanding of the interplay between c-di-GMP, RpoN and T3SS and the potential role of c-di-GMP in T3SS regulation among a wide range of bacterial pathogens. [source] | ||||||||||