...Ramesh Rijal; Sara A. Kirolos; Ryan J. Rahman; Richard H. Gomer ABSTRACT Dictyostelium discoideum is a unicellular eukaryote that eats bacteria, and eventually outgrows the bacteria. D. discoideum cells accumulate extracellular polyphosphate (polyP), and the polyP concentration increases...

...Jeffrey A. Hadwiger; Huaqing Cai; Ramee G. Aranda; Saher Fatima ABSTRACT The Dictyostelium atypical mitogen-activated protein kinase (MAPK) Erk2 is required for chemotactic responses to cAMP as amoeba undergo multicellular development. In this study, Erk2 was found to be essential for the cAMP...

...Günther Gerisch; Jana Prassler; Mary Ecke ABSTRACT In multi-nucleate cells of Dictyostelium , cytokinesis is performed by unilateral cleavage furrows that ingress the large cells from their border. We use a septase (sepA)-null mutant with delayed cytokinesis to show that in anaphase a pattern...

...Yiwei Zhang; Hui Tu; Yazhou Hao; Dong Li; Yihong Yang; Ye Yuan; Zhonglong Guo; Lei Li; Haibin Wang; Huaqing Cai ABSTRACT Macropinocytosis mediates non-selective bulk uptake of extracellular fluid. It is the major route by which axenic Dictyostelium cells obtain nutrients and has emerged...

...Shigenori Hirose; Mariko Katoh-Kurasawa; Gad Shaulsky ABSTRACT Allorecognition and tissue formation are interconnected processes that require signaling between matching pairs of the polymorphic transmembrane proteins TgrB1 and TgrC1 in Dictyostelium . Extracellular and intracellular cAMP signaling...

... distinct, but conserved, glycine residues in both the Dictyostelium piaA gene and its human ortholog, RICTOR . The two conserved residues are spaced ∼50 amino acids apart, and both are embedded within a conserved region falling in between the Ras-GEFN2 and Rictor­_V domains. The effects of point mutations...

...Thomas D. Williams; Sew-Yeu Peak-Chew; Peggy Paschke; Robert R. Kay ABSTRACT Macropinocytosis is an actin-driven process of large-scale and non-specific fluid uptake used for feeding by some cancer cells and the macropinocytosis model organism Dictyostelium discoideum . In Dictyostelium...

... of reactive oxygen species, deprivation of nutrients and the lumenal accumulation of toxic metals are essential to kill ingested bacteria or inhibit the growth of intracellular pathogens. Here, we used the soil amoeba Dictyostelium discoideum , a professional phagocyte that digests bacteria for nutritional...

...Lauriane Mas; Adeline Cieren; Christian Delphin; Agnès Journet; Laurence Aubry ABSTRACT Arrestins are key adaptor proteins that control the fate of cell-surface membrane proteins and modulate downstream signaling cascades. The Dictyostelium discoideum genome encodes six arrestin-related proteins...

...Weiye Wang; Song Chen; Satarupa Das; Wolfgang Losert; Carole A. Parent ABSTRACT Dictyostelium discoideum cells transport adenylyl cyclase A (ACA)-containing vesicles to the back of polarized cells to relay exogenous cAMP signals during chemotaxis. Fluorescence in situ hybridization (FISH...

...-proteins and the cytoskeleton. Small G-proteins Cytoskeleton Symmetry Dictyostelium Chemotaxis The method for quantifying reflection symmetry is an adaptation of the method described above for rotational symmetry. It requires additional definitions for the symmetry axis and for odd...

...Thomas D. Williams; Robert R. Kay ABSTRACT Macropinocytosis is a conserved endocytic process used by Dictyostelium amoebae for feeding on liquid medium. To further Dictyostelium as a model for macropinocytosis, we developed a high-throughput flow cytometry assay to measure macropinocytosis...

...Shigenori Hirose; Gong Chen; Adam Kuspa; Gad Shaulsky ABSTRACT Allorecognition is a key factor in Dictyostelium development and sociality. It is mediated by two polymorphic transmembrane proteins, TgrB1 and TgrC1, which contain extracellular immunoglobulin domains. TgrB1 and TgrC1 are necessary...

...Patrick M. Suess; Jacob Watson; Wensheng Chen; Richard H. Gomer ABSTRACT Linear chains of five to hundreds of phosphates called polyphosphate are found in organisms ranging from bacteria to humans, but their function is poorly understood. In Dictyostelium discoideum , polyphosphate is used...

...Peter A. Thomason; Jason S. King; Robert H. Insall ABSTRACT The steps leading to constitutive exocytosis are poorly understood. In Dictyostelium WASH complex mutants, exocytosis is blocked, so cells that take up fluorescent dextran from the medium retain it and remain fluorescent. Here, we...

...Barbara Pergolizzi; Enrico Bracco; Salvatore Bozzaro ABSTRACT Cyclic AMP (cAMP) binding to G-protein-coupled receptors (GPCRs) orchestrates chemotaxis and development in Dictyostelium. By activating the RasC–TORC2–PKB (PKB is also known as AKT in mammals) module, cAMP regulates cell polarization...

.... Food is a common source of mutagens, but little is known about how nutritional factors cause lasting genetic changes in the consuming organism. Here, we describe an unusual genetic interaction between DNA repair in the unicellular amoeba Dictyostelium discoideum and its natural bacterial food source...

... by promoting enrichment of repair factors at damage sites through ADP-ribose interaction domains. Here, we exploit the simple eukaryote Dictyostelium to uncover a role for ADP-ribosylation in regulating DNA interstrand crosslink repair and redundancy of this pathway with non-homologous end-joining (NHEJ...

...Mariko Katoh-Kurasawa; Balaji Santhanam; Gad Shaulsky ABSTRACT The GATA transcription factor GtaG is conserved in Dictyostelids and is essential for terminal differentiation in Dictyostelium discoideum , but its function is not well understood. Here, we show that gtaG is expressed in prestalk cells...

...Cheng-Lin Frank Li; Gong Chen; Amanda Nicole Webb; Gad Shaulsky ABSTRACT Cell surface adhesion receptors play diverse functions in multicellular development. In Dictyostelium , two immunoglobulin-like adhesion proteins, TgrB1 and TgrC1, are essential components with dual roles in morphogenesis...