Experts and Doctors on chemotaxis in New York, United States


Locale: New York, United States
Topic: chemotaxis

Top Publications

  1. Ashton A, Yokota R, John G, Zhao S, Suadicani S, Spray D, et al. Inhibition of endothelial cell migration, intercellular communication, and vascular tube formation by thromboxane A(2). J Biol Chem. 1999;274:35562-70 pubmed
    ..Thus, this finding that TXA(2) mimetics can prevent HEC migration and tube formation, possibly by impairing intercellular communication, suggests that antagonizing TXA(2) signaling might enhance vascularization of ischemic tissue. ..
  2. Dodd J, Jessell T. Axon guidance and the patterning of neuronal projections in vertebrates. Science. 1988;242:692-9 pubmed
    ..Several guidance cues may operate in a coordinated way to generate the distinct axonal trajectories of individual neurons. ..
  3. Su W, Yeku O, Olepu S, Genna A, Park J, Ren H, et al. 5-Fluoro-2-indolyl des-chlorohalopemide (FIPI), a phospholipase D pharmacological inhibitor that alters cell spreading and inhibits chemotaxis. Mol Pharmacol. 2009;75:437-46 pubmed publisher
    ..However, FIPI does inhibit PLD regulation of F-actin cytoskeleton reorganization, cell spreading, and chemotaxis, indicating potential utility for it as a therapeutic for autoimmunity and cancer metastasis. ..
  4. Mintz C, Barrett K, Smith S, Benson D, Harrison N. Anesthetics interfere with axon guidance in developing mouse neocortical neurons in vitro via a ?-aminobutyric acid type A receptor mechanism. Anesthesiology. 2013;118:825-33 pubmed publisher
    ..The finding that GAs interfere with axon guidance, and thus potentially with circuit formation, represents a novel form of anesthesia neurotoxicity in brain development. ..
  5. Persaud K, Tille J, Liu M, Zhu Z, Jimenez X, Pereira D, et al. Involvement of the VEGF receptor 3 in tubular morphogenesis demonstrated with a human anti-human VEGFR-3 monoclonal antibody that antagonizes receptor activation by VEGF-C. J Cell Sci. 2004;117:2745-56 pubmed
    ..Similar results were obtained with HUVECs. Together, these findings point to a role for VEGFR-3 in vascular tubular morphogenesis and highlight the utility of hF4-3C5 as a tool for the investigation of the biology of VEGFR-3. ..
  6. Fishilevich E, Domingos A, Asahina K, Naef F, Vosshall L, Louis M. Chemotaxis behavior mediated by single larval olfactory neurons in Drosophila. Curr Biol. 2005;15:2086-96 pubmed
    ..This study is the first behavioral demonstration that formation of olfactory percepts involves the combinatorial integration of information transmitted by multiple ORs. ..
  7. Wyckoff J, Wang W, Lin E, Wang Y, Pixley F, Stanley E, et al. A paracrine loop between tumor cells and macrophages is required for tumor cell migration in mammary tumors. Cancer Res. 2004;64:7022-9 pubmed
    ..This work provides the first direct evidence for a synergistic interaction between macrophages and tumor cells during cell migration in vivo and indicates a mechanism for how macrophages may contribute to metastasis. ..
  8. Davalos D, Grutzendler J, Yang G, Kim J, Zuo Y, Jung S, et al. ATP mediates rapid microglial response to local brain injury in vivo. Nat Neurosci. 2005;8:752-8 pubmed
    ..Thus, extracellular ATP regulates microglial branch dynamics in the intact brain, and its release from the damaged tissue and surrounding astrocytes mediates a rapid microglial response towards injury. ..
  9. Zisa D, Shabbir A, Mastri M, Taylor T, Aleksic I, McDaniel M, et al. Intramuscular VEGF activates an SDF1-dependent progenitor cell cascade and an SDF1-independent muscle paracrine cascade for cardiac repair. Am J Physiol Heart Circ Physiol. 2011;301:H2422-32 pubmed publisher
    ..Given that recent clinical trials of cardiac repair based on the use of marrow-mobilizing agents have been disappointing, the proposed dual therapeutic modality warrants further investigation. ..

More Information


  1. Guinamard R, Signoret N, Ishiai M, Marsh M, Kurosaki T, Ravetch J, et al. B cell antigen receptor engagement inhibits stromal cell-derived factor (SDF)-1alpha chemotaxis and promotes protein kinase C (PKC)-induced internalization of CXCR4. J Exp Med. 1999;189:1461-6 pubmed
    ..These studies suggest that one pathway by which BCR stimulation results in inhibition of SDF-1alpha migration is through PKC-dependent downregulation of CXCR4. ..
  2. Roussos E, Condeelis J, Patsialou A. Chemotaxis in cancer. Nat Rev Cancer. 2011;11:573-87 pubmed publisher
    ..The central importance of chemotaxis in cancer progression is highlighted by discussion of the use of chemotaxis as a prognostic marker, a treatment end point and a target of therapeutic intervention. ..
  3. Cronshaw D, Nie Y, Waite J, Zou Y. An essential role of the cytoplasmic tail of CXCR4 in G-protein signaling and organogenesis. PLoS ONE. 2010;5:e15397 pubmed publisher
  4. Yao Y, Tsirka S. The C terminus of mouse monocyte chemoattractant protein 1 (MCP1) mediates MCP1 dimerization while blocking its chemotactic potency. J Biol Chem. 2010;285:31509-16 pubmed publisher
  5. Peliti M, Chuang J, Shaham S. Directional locomotion of C. elegans in the absence of external stimuli. PLoS ONE. 2013;8:e78535 pubmed publisher
    ..This directional behavior requires sensory neurons, but appears to be independent of known sensory signal-transduction pathways. Our results suggest that long-range directional behavior of C. elegans may not be driven by sensory cues. ..
  6. Bacaj T, Tevlin M, Lu Y, Shaham S. Glia are essential for sensory organ function in C. elegans. Science. 2008;322:744-7 pubmed publisher
    ..FIG-1 protein functions extracellularly, is essential for neuronal dye uptake, and also affects behavior. Our results suggest that glia are required for multiple aspects of sensory organ function...
  7. Mello B, Tu Y. Effects of adaptation in maintaining high sensitivity over a wide range of backgrounds for Escherichia coli chemotaxis. Biophys J. 2007;92:2329-37 pubmed
  8. Kermani P, Rafii D, Jin D, Whitlock P, Schaffer W, Chiang A, et al. Neurotrophins promote revascularization by local recruitment of TrkB+ endothelial cells and systemic mobilization of hematopoietic progenitors. J Clin Invest. 2005;115:653-63 pubmed
  9. Garcia M, Ray S, Brown I, Irom J, Brazill D. PakD, a putative p21-activated protein kinase in Dictyostelium discoideum, regulates actin. Eukaryot Cell. 2014;13:119-26 pubmed publisher
    ..Taken together, the results suggest that PakD is part of a pathway coordinating F-actin organization during development. ..
  10. Kodali R, Kim W, Galaria I, Miller C, Schecter A, Lira S, et al. CCL11 (Eotaxin) induces CCR3-dependent smooth muscle cell migration. Arterioscler Thromb Vasc Biol. 2004;24:1211-6 pubmed
    ..Because CCL11 is expressed abundantly in SMC-rich areas of the atherosclerotic plaque and in injured arteries, it may play an important role in regulating SMC migration. ..
  11. Janardhan A, Swigut T, Hill B, Myers M, Skowronski J. HIV-1 Nef binds the DOCK2-ELMO1 complex to activate rac and inhibit lymphocyte chemotaxis. PLoS Biol. 2004;2:E6 pubmed
    ..This interaction enables Nef to influence multiple aspects of T cell function and thus provides an important mechanism by which Nef impacts pathogenesis by primate lentiviruses. ..
  12. Duran M, Rahman A, Colten M, Brazill D. Dictyostelium discoideum paxillin regulates actin-based processes. Protist. 2009;160:221-32 pubmed publisher
    ..Taken together, the data suggest that proper expression of PaxB is vital for the regulation of development and actin-dependent processes. ..
  13. Das S, Sarrou E, Podgrabinska S, Cassella M, Mungamuri S, Feirt N, et al. Tumor cell entry into the lymph node is controlled by CCL1 chemokine expressed by lymph node lymphatic sinuses. J Exp Med. 2013;210:1509-28 pubmed publisher
    ..These data identify a novel function for CCL1-CCR8 in metastasis and lymph node LECs as a critical checkpoint for the entry of metastases into the lymph nodes. ..
  14. Robbiani D, Finch R, Jager D, Muller W, Sartorelli A, Randolph G. The leukotriene C(4) transporter MRP1 regulates CCL19 (MIP-3beta, ELC)-dependent mobilization of dendritic cells to lymph nodes. Cell. 2000;103:757-68 pubmed
    ..Thus, MRP-1 regulates DC migration to lymph nodes, apparently by transporting LTC(4), which in turn promotes chemotaxis to CCL19 and mobilization of DCs from the epidermis...
  15. PERRON J, Dodd J. Inductive specification and axonal orientation of spinal neurons mediated by divergent bone morphogenetic protein signaling pathways. Neural Dev. 2011;6:36 pubmed publisher
    ..A model is proposed whereby selective engagement of BMP receptor subunits underlies choice of signaling pathway. ..
  16. Chang S, Johnston R, Fr√łkjaer Jensen C, Lockery S, Hobert O. MicroRNAs act sequentially and asymmetrically to control chemosensory laterality in the nematode. Nature. 2004;430:785-9 pubmed
    ..Thus, an inverse distribution of two sequentially acting miRNAs in two bilaterally symmetric neurons controls laterality of the nematode chemosensory system. ..
  17. Harpel P, Haque N. Chemokine receptor-8: potential role in atherogenesis. Isr Med Assoc J. 2002;4:1025-7 pubmed
    ..CCL1 increased metalloproteinase-2 production by HUVEC, an activity that enables these cells to remodel the vascular matrix. These studies suggest that CCR8 may play an important role in arterial wall pathology. ..
  18. Randolph G, Ochando J, Partida Sanchez S. Migration of dendritic cell subsets and their precursors. Annu Rev Immunol. 2008;26:293-316 pubmed
    ..Finally, to gain a more molecular appreciation of the specialized migratory properties of DCs, we review the signaling cascades that govern the process of DC migration. ..
  19. Zhu Z, Hattori K, Zhang H, Jimenez X, Ludwig D, Dias S, et al. Inhibition of human leukemia in an animal model with human antibodies directed against vascular endothelial growth factor receptor 2. Correlation between antibody affinity and biological activity. Leukemia. 2003;17:604-11 pubmed
    ..It further underscores the efforts to identify antibodies of high affinity for enhanced antiangiogenic and antitumor activities...
  20. Hu X, Park Min K, Ho H, Ivashkiv L. IFN-gamma-primed macrophages exhibit increased CCR2-dependent migration and altered IFN-gamma responses mediated by Stat1. J Immunol. 2005;175:3637-47 pubmed
    ..Our results also suggest that, in addition to inducing hypersensitivity to inflammatory stimuli, IFN priming delivers a homeostatic signal by attenuating IFN-gamma induction of certain tissue-destructive genes. ..
  21. Yurchenko V, O Connor M, Dai W, Guo H, Toole B, Sherry B, et al. CD147 is a signaling receptor for cyclophilin B. Biochem Biophys Res Commun. 2001;288:786-8 pubmed
    ..These results suggest that CD147 serves as a receptor for extracellular cyclophilins. ..
  22. Haque N, Fallon J, Taubman M, Harpel P. The chemokine receptor CCR8 mediates human endothelial cell chemotaxis induced by I-309 and Kaposi sarcoma herpesvirus-encoded vMIP-I and by lipoprotein(a)-stimulated endothelial cell conditioned medium. Blood. 2001;97:39-45 pubmed
    ..These results indicate that CCR8 is an endothelial receptor that may modulate endothelial function. ..
  23. Haque N, Fallon J, Pan J, Taubman M, Harpel P. Chemokine receptor-8 (CCR8) mediates human vascular smooth muscle cell chemotaxis and metalloproteinase-2 secretion. Blood. 2004;103:1296-304 pubmed
    ..The induction of CCR8 and CCL1/TCA3 under conditions associated with VSMC proliferation and migration raises the possibility that CCR8 may play an important role in vessel wall pathology. ..
  24. DesMarais V, Yamaguchi H, Oser M, Soon L, Mouneimne G, Sarmiento C, et al. N-WASP and cortactin are involved in invadopodium-dependent chemotaxis to EGF in breast tumor cells. Cell Motil Cytoskeleton. 2009;66:303-16 pubmed publisher
  25. Min S, Ai M, Shin S, Suh G. Dedicated olfactory neurons mediating attraction behavior to ammonia and amines in Drosophila. Proc Natl Acad Sci U S A. 2013;110:E1321-9 pubmed publisher
    ..This labeled-line mode of amine coding appears to be hardwired to attraction behavior...
  26. Pagler T, Wang M, Mondal M, Murphy A, Westerterp M, Moore K, et al. Deletion of ABCA1 and ABCG1 impairs macrophage migration because of increased Rac1 signaling. Circ Res. 2011;108:194-200 pubmed publisher
    ..In contrast free cholesterol loading of macrophages leads to imbalanced Rac1/Rho activities and impaired chemotaxis...
  27. Tepper O, Carr J, Allen R, Chang C, Lin C, Tanaka R, et al. Decreased circulating progenitor cell number and failed mechanisms of stromal cell-derived factor-1alpha mediated bone marrow mobilization impair diabetic tissue repair. Diabetes. 2010;59:1974-83 pubmed publisher
    ..Plerixafor represents a potential therapeutic agent for improving ischemia-mediated pathology associated with diabetes by reducing bone marrow SDF-1alpha, restoring normal PC mobilization and tissue healing. ..
  28. Ishihara D, Dovas A, Park H, Isaac B, Cox D. The chemotactic defect in wiskott-Aldrich syndrome macrophages is due to the reduced persistence of directional protrusions. PLoS ONE. 2012;7:e30033 pubmed publisher
  29. Tsunozaki M, Chalasani S, Bargmann C. A behavioral switch: cGMP and PKC signaling in olfactory neurons reverses odor preference in C. elegans. Neuron. 2008;59:959-71 pubmed publisher
    ..These results suggest that alternative modes of neurotransmission can couple one sensory neuron to opposite behavioral outputs. ..
  30. Zagzag D, Esencay M, Mendez O, Yee H, Smirnova I, Huang Y, et al. Hypoxia- and vascular endothelial growth factor-induced stromal cell-derived factor-1alpha/CXCR4 expression in glioblastomas: one plausible explanation of Scherer's structures. Am J Pathol. 2008;173:545-60 pubmed publisher
    ..These studies offer one plausible molecular basis and explanation of the formation of Scherer's structures in glioma patients. ..
  31. Kraemer R, Baker P, Kent K, Ye Y, Han J, Tejada R, et al. Decreased neurotrophin TrkB receptor expression reduces lesion size in the apolipoprotein E-null mutant mouse. Circulation. 2005;112:3644-53 pubmed
    ..These data demonstrate, for the first time, a role for the neurotrophin TrkB receptor in atherosclerotic lesion development. ..
  32. Zou Y, Kottmann A, Kuroda M, Taniuchi I, Littman D. Function of the chemokine receptor CXCR4 in haematopoiesis and in cerebellar development. Nature. 1998;393:595-9 pubmed
    ..These results may be important for designing strategies to block HIV entry into cells and for understanding mechanisms of pathogenesis in AIDS dementia. ..
  33. Tchou Wong K, Fok S, Rubin J, Pixley F, Condeelis J, Braet F, et al. Rapid chemokinetic movement and the invasive potential of lung cancer cells; a functional molecular study. BMC Cancer. 2006;6:151 pubmed
    ..Understanding the regulation of polarity in the context of cell motility is important in order to improve control and inhibition of invasion and metastasis. ..
  34. Wichterle H, Alvarez Dolado M, Erskine L, Alvarez Buylla A. Permissive corridor and diffusible gradients direct medial ganglionic eminence cell migration to the neocortex. Proc Natl Acad Sci U S A. 2003;100:727-32 pubmed
    ..In addition, we propose that chemotactic guidance cues superimposed over the permissive corridor facilitate efficient dorsal migration of MGE cells. ..
  35. Coniglio S, Eugenin E, Dobrenis K, Stanley E, West B, Symons M, et al. Microglial stimulation of glioblastoma invasion involves epidermal growth factor receptor (EGFR) and colony stimulating factor 1 receptor (CSF-1R) signaling. Mol Med. 2012;18:519-27 pubmed publisher
  36. Ortiz C, Faumont S, Takayama J, Ahmed H, Goldsmith A, Pocock R, et al. Lateralized gustatory behavior of C. elegans is controlled by specific receptor-type guanylyl cyclases. Curr Biol. 2009;19:996-1004 pubmed publisher
    ..Our findings broaden our understanding of lateralities in neural function, provide insights into how this laterality is molecularly encoded, and reveal an unusual multitude of molecules involved in gustatory signal transduction. ..
  37. Butler S, Dodd J. A role for BMP heterodimers in roof plate-mediated repulsion of commissural axons. Neuron. 2003;38:389-401 pubmed
    ..Our findings suggest that a GDF7:BMP7 heterodimer functions as a roof plate-derived repellent that establishes the initial ventral trajectory of commissural axons. ..
  38. Mouneimne G, DesMarais V, Sidani M, Scemes E, Wang W, Song X, et al. Spatial and temporal control of cofilin activity is required for directional sensing during chemotaxis. Curr Biol. 2006;16:2193-205 pubmed
    ..These results indicate that local activation of cofilin by PLC and its global inactivation by LIMK phosphorylation combine to generate the local asymmetry of actin polymerization required for chemotaxis. ..
  39. Hattori K, Heissig B, Wu Y, Dias S, Tejada R, Ferris B, et al. Placental growth factor reconstitutes hematopoiesis by recruiting VEGFR1(+) stem cells from bone-marrow microenvironment. Nat Med. 2002;8:841-9 pubmed
    ..Thus, PlGF promotes recruitment of VEGFR1(+) HSCs from a quiescent to a proliferative BM microenvironment, favoring differentiation, mobilization and reconstitution of hematopoiesis. ..
  40. Renault A, Lehmann R. Follow the fatty brick road: lipid signaling in cell migration. Curr Opin Genet Dev. 2006;16:348-54 pubmed
    ..In all three scenarios, the contributions of these genes in the stationary and migrating cells are being teased apart by genetic studies and direct observation, with exciting results. ..
  41. Garcia R, Nguyen L, Brazill D. Dictyostelium discoideum SecG interprets cAMP-mediated chemotactic signals to influence actin organization. Cytoskeleton (Hoboken). 2013;70:269-80 pubmed publisher
    ..Taken together, the results suggest proper SecG levels are needed for appropriate response to cAMP signaling in order to coordinate F-actin organization during development. ..
  42. Billerbeck E, Horwitz J, Labitt R, Donovan B, Vega K, Budell W, et al. Characterization of human antiviral adaptive immune responses during hepatotropic virus infection in HLA-transgenic human immune system mice. J Immunol. 2013;191:1753-64 pubmed publisher
    ..The adenovirus reporter system used in our study may serve as simple in vivo method to evaluate future strategies for improving human intrahepatic immune responses in humanized mice. ..
  43. Chen H, Edwards R, Tucci S, Bu P, Milsom J, Lee S, et al. Chemokine 25-induced signaling suppresses colon cancer invasion and metastasis. J Clin Invest. 2012;122:3184-96 pubmed publisher
    ..Overall, these data indicate that CCL25 and CCR9 regulate CRC progression and invasion and further demonstrate an appropriate in vivo experimental system to study CRC progression in the native colon microenvironment. ..
  44. Hotchkiss K, Basile C, Spring S, Bonuccelli G, Lisanti M, Terman B. TEM8 expression stimulates endothelial cell adhesion and migration by regulating cell-matrix interactions on collagen. Exp Cell Res. 2005;305:133-44 pubmed
    ..Taken together, these results indicate that TEM8 plays a positive role in endothelial cell activities related to angiogenesis. ..
  45. Treptow N, Shuman H. Allele-specific malE mutations that restore interactions between maltose-binding protein and the inner-membrane components of the maltose transport system. J Mol Biol. 1988;202:809-22 pubmed
    ..The locations of different malE suppressor mutations indicate specific regions on MBP that are important for interacting with MalF and MalG...
  46. Ray S, Chen Y, Ayoung J, Hanna R, Brazill D. Phospholipase D controls Dictyostelium development by regulating G protein signaling. Cell Signal. 2011;23:335-43 pubmed publisher
    ..These results suggest that phospholipase D activity is required for CMF to alter the kinetics of cAMP-induced G protein signaling. ..
  47. PERRON J, Dodd J. ActRIIA and BMPRII Type II BMP receptor subunits selectively required for Smad4-independent BMP7-evoked chemotaxis. PLoS ONE. 2009;4:e8198 pubmed publisher
    ..We suggest a model of a BMP receptor complex in which the coordinated activity of ActRIIA and BMPRII receptor subunits selectively mediates the chemotactic response to BMP7. ..
  48. Magalhaes M, Glogauer M. Pivotal Advance: Phospholipids determine net membrane surface charge resulting in differential localization of active Rac1 and Rac2. J Leukoc Biol. 2010;87:545-55 pubmed publisher
  49. Ricardo S, Lehmann R. An ABC transporter controls export of a Drosophila germ cell attractant. Science. 2009;323:943-6 pubmed publisher
    ..Components of this unconventional export pathway are highly conserved, suggesting that this pathway may control the production of similarly modified chemoattractants in organisms ranging from yeast to humans...
  50. Louis M, Huber T, Benton R, Sakmar T, Vosshall L. Bilateral olfactory sensory input enhances chemotaxis behavior. Nat Neurosci. 2008;11:187-99 pubmed
    ..We found additional evidence that the overall accuracy of navigation is enhanced by the increase in the signal-to-noise ratio conferred by bilateral sensory input. ..
  51. Qazi H, Shi Z, Tarbell J. Fluid shear stress regulates the invasive potential of glioma cells via modulation of migratory activity and matrix metalloproteinase expression. PLoS ONE. 2011;6:e20348 pubmed publisher
    ..These models should be useful for the continued study of interstitial flow effects on processes that affect tumor progression. ..
  52. Yurchenko V, Zybarth G, O Connor M, Dai W, Franchin G, Hao T, et al. Active site residues of cyclophilin A are crucial for its signaling activity via CD147. J Biol Chem. 2002;277:22959-65 pubmed
    ..These results establish cyclophilins as natural ligands for CD147 and suggest an unusual, rotamase-dependent mechanism of signaling. ..
  53. Asahina K, Louis M, Piccinotti S, Vosshall L. A circuit supporting concentration-invariant odor perception in Drosophila. J Biol. 2009;8:9 pubmed publisher
    ..We investigated how subsets of larval OSNs with overlapping but distinct response properties cooperate to mediate perception of a given odorant across a range of concentrations...
  54. Liu J, Guan X, Ma X. Interferon regulatory factor 1 is an essential and direct transcriptional activator for interferon {gamma}-induced RANTES/CCl5 expression in macrophages. J Biol Chem. 2005;280:24347-55 pubmed
    ..This study uncovers a novel IFNgamma-induced pathway in RANTES expression mediated by IRF-1 in macrophages and elucidates an important host defense mechanism against neoplastic transformation. ..
  55. Feugier P, Li N, Jo D, Shieh J, MacKenzie K, Lesesve J, et al. Osteopetrotic mouse stroma with thrombopoietin, c-kit ligand, and flk-2 ligand supports long-term mobilized CD34+ hematopoiesis in vitro. Stem Cells Dev. 2005;14:505-16 pubmed
  56. Hu L, Roth J, Brooks P, Luty J, Karpatkin S. Thrombin up-regulates cathepsin D which enhances angiogenesis, growth, and metastasis. Cancer Res. 2008;68:4666-73 pubmed publisher
    ..02). Thus, thrombin-induced CD contributes to the malignant phenotype by inducing tumor cell migration, nodule growth, metastasis, and angiogenesis. CD-induced angiogenesis requires the proteolytic activation of MMP-9. ..
  57. Asahina K, Benton R. Smell and taste on a high: symposium on chemical senses: from genes to perception. EMBO Rep. 2007;8:634-8 pubmed
  58. Kim J, Dustin M. Innate response to focal necrotic injury inside the blood-brain barrier. J Immunol. 2006;177:5269-77 pubmed
    ..The astrocytes network established a cytoplasmic Ca2+ gradient that preceded the microglial response. This is consistent with astrocyte-microglial collaboration to mount this innate response that excludes blood leukocytes. ..
  59. Chen S, Segall J. EppA, a putative substrate of DdERK2, regulates cyclic AMP relay and chemotaxis in Dictyostelium discoideum. Eukaryot Cell. 2006;5:1136-46 pubmed
    ..Our studies indicate that EppA regulates extracellular cAMP-induced signal relay and chemotaxis of Dictyostelium. ..