dictyNews Electronic Edition Volume 43, number 20 August 25, 2017 Please submit abstracts of your papers as soon as they have been accepted for publication by sending them to dicty@northwestern.edu or by using the form at http://dictybase.org/db/cgi-bin/dictyBase/abstract_submit. Back issues of dictyNews, the Dicty Reference database and other useful information is available at dictyBase - http://dictybase.org. Follow dictyBase on twitter: http://twitter.com/dictybase ========= Abstracts ========= Biological activities of novel derivatives of differentiation-inducing factor 3 from Dictyostelium discoideum Katsunori Takahashi,a Haruhisa Kikuchi,*,b Van Hai Nguyen,b Yoshiteru Oshima,b Hirotaka Ishigaki,a Junko Nakajima-Shimada,c and Yuzuru Kubohara, *,d a Department of Medical Technology, Faculty of Health Science, Gunma Paz College; Takasaki 370-0006, Japan b Laboratory of Natural Product Chemistry, Graduate School of Pharmaceutical Sciences, Tohoku University; Sendai 980-8578, Japan c Department of Basic Sciences for Medicine, Graduate School of Health Sciences, Gunma University; Maebashi 371-8514, Japan d Laboratory of Health and Life Science, Graduate School of Heath and Sports Science, Juntendo University; Inzai, Chiba 270-1695, Japan Biological & Pharmaceutical Bulletin, in press. Abstract Differentiation-inducing factor-3 (DIF-3; 1-(3-chloro-2,6-dihydroxy-4- methoxyphenyl)hexan-1-one), which is found in the cellular slime mold Dictyostelium discoideum, is a potential candidate compound for the development of new medicines; DIF-3 and its derivatives possess several beneficial biological activities, including anti-tumor, anti-Trypanosoma cruzi, and immunoregulatory effects. To assess the relationship between the biological activities of DIF-3 and its chemical structure, particularly in regard to its alkoxy group and the length of the alkyl chains at the acyl group, we synthesized two derivatives of DIF-3, DIF-3(+3) and Hex-DIF-3, and investigated their biological activities in vitro. At micro-molar levels, DIF-3(+3) and Hex-DIF-3 exhibited strong anti-proliferative effects in tumor cell cultures, but their anti-T. cruzi activities at 1 microM in vitro were not as strong as those of other known DIF derivatives. In addition, Hex-DIF-3 at 5 microM significantly suppressed mitogen-induced interleukin-2 production in vitro in Jurkat T cells. These results suggest that DIF-3(+3) and Hex-DIF-3 are promising leads for the development of anti-cancer and immunosuppressive agents. submitted by: Yuzuru Kubohara [ykuboha@juntendo.ac.jp] ———————————————————————————————————————— Actin assembly mechanisms at a glance Klemens Rottner 1,2, Jan Faix 3, Sven Bogdan 4, Stefan Linder 5 and Eugen Kerkhoff 6 1 Division of Molecular Cell Biology, Zoological Institute, Technische Universität Braunschweig, 38106 Braunschweig, Germany; 2 Department of Cell Biology, Helmholtz Centre for Infection Research, 38124 Braunschweig, Germany; 3 Institute for Biophysical Chemistry, Hannover Medical School, 30625 Hannover, Germany; 4 Institute for Physiology and Pathophysiology, Department of Molecular Cell Physiology, Philipps-University of Marburg, 35032 Marburg, Germany; 5 Institute for Medical Microbiology, Virology and Hygiene, University Medical Center Eppendorf, 20246 Hamburg, Germany; 6 Department of Neurology, University Hospital Regensburg, 93053 Regensburg, Germany. J. Cell Sci., in press The actin cytoskeleton and associated motor proteins provide the driving forces for establishing the astonishing morphological diversity and dynamics of mammalian cells. Aside from functions in protruding and contracting cell membranes for motility, differentiation or cell division, the actin cytoskeleton provides forces to shape and move intracellular membranes of organelles and vesicles. To establish the many different actin assembly functions required in time and space, actin nucleators are targeted to specific subcellular compartments, thereby restricting the generation of specific actin filament structures to those sites. Recent research has revealed a highly coordinated targeting and activation of actin filament nucleators, elongators and myosin motors by conserved protein complexes, in order to orchestrate force generation. In this Cell Science at a Glance article and the accompanying poster, we summarize and discuss the current knowledge on the corresponding protein complexes and their modes of action in actin nucleation, elongation and force generation. submitted by: Jan Faix [faix.jan@mh-hannover.de] ============================================================== [End dictyNews, volume 43, number 20]