Dicty News Electronic Edition Volume 21, number 10 October 3, 2003 Please submit abstracts of your papers as soon as they have been accepted for publication by sending them to dicty@northwestern.edu. Back issues of Dicty-News, the Dicty Reference database and other useful information is available at dictyBase - http://dictybase.org. ============= Abstracts ============= Cell-death alternative model organisms: why and which? Golstein P, Aubry L, Levraud JP. Centre d'Immunologie de Marseille-Luminy, CNRS-INSERM-l'Universite de la Mediteranee, Parc Scientifique de Luminy, Case 906, 13288 Marseille cedex 9, France. Nat Rev Mol Cell Biol. 2003 in press Classical model organisms have helped greatly in our understanding of cell death but, at the same time, might have constrained it. The use of other, non-classical model organisms from all biological kingdoms could reveal undetected molecular pathways and better-defined morphological types of cell death. Here we discuss what is known and what might be learned from these alternative model systems. Submitted by: Pierre Golstein [golstein@ciml.univ-mrs.fr] ----------------------------------------------------------------------------- The cyclase associated protein CAP as regulator of cell polarity and cAMP signaling in Dictyostelium Angelika A. Noegel, Rosemarie Blau-Wasser, Hameeda Sultana, Rolf Müller, Lars Israel, Michael Schleicher, Hitesh Patel, Cornelis J. Weijer accepted: Mol. Biol. Cell CAP (cyclase associated protein) is an evolutionarily conserved regulator of the G-actin/F-actin ratio and, in yeast, is involved in regulating the adenylyl cyclase activity. We show that cell polarization, F-actin organization and phototaxis are altered in a Dictyostelium CAP knockout mutant. Furthermore, in complementation assays we determined the roles of the individual domains in signaling and regulation of the actin cytoskeleton. We studied in detail the adenylyl cyclase activity and found that the mutant cells have normal levels of the aggregation phase specific adenylyl cyclase (ACA) and that receptor mediated activation is intact. However, cAMP relay which is responsible for the generation of propagating cAMP waves that control the chemotactic aggregation of starving Dictyostelium cells was altered, and the cAMP induced cGMP production was significantly reduced. The data suggest an interaction of CAP with adenylyl cyclase in Dictyostelium and an influence on signaling pathways directly as well as through its function as a regulatory component of the cytoskeleton. Submitted by: Michael Schleicher [schleicher@lrz.uni-muenchen.de] =============================================================================== [End Dicty News, volume 21, number 10]