RRC ID 6653
Author Traynor D, Milne JL, Insall RH, Kay RR.
Title Ca(2+) signalling is not required for chemotaxis in Dictyostelium.
Journal EMBO J
Abstract Dictyostelium cells can move rapidly towards a source of cyclic-AMP (cAMP). This chemoattractant is detected by G-protein-linked receptors, which trigger a signalling cascade including a rapid influx of Ca(2+). We have disrupted an inositol 1,4,5-trisphosphate (InsP(3)) receptor-like gene, iplA, to produce null cells in which Ca(2+) entry in response to chemoattractants is abolished, as is the normal increase in free cytosolic Ca(2+) ([Ca(2+)](c)) that follows chemotactic stimulation. However, the resting [Ca(2+)](c) is similar to wild type. This mutant provides a test for the role of Ca(2+) influx in both chemotaxis and the signalling cascade that controls it. The production of cyclic-GMP and cAMP, and the activation of the MAP kinase, DdERK2, triggered from the cAMP receptor, are little perturbed in the mutant; mobilization of actin into the cytoskeleton also follows similar kinetics to wild type. Mutant cells chemotax efficiently towards cAMP or folic acid and their sensitivity to cAMP is similar to wild type. Finally, they move at similar speeds to wild-type cells, with or without chemoattractant. We conclude that Ca(2+) signalling is not necessary for chemotaxis to cAMP.
Volume 19(17)
Pages 4846-54
Published 2000-9-1
DOI 10.1093/emboj/19.17.4846
PMID 10970875
PMC PMC302083
MeSH Amino Acid Sequence Animals Calcium / metabolism Calcium Channels / chemistry Calcium Channels / genetics Calcium Channels / physiology Calcium Signaling* Chemotaxis* Dictyostelium / cytology* Dictyostelium / metabolism Inositol 1,4,5-Trisphosphate Receptors Molecular Sequence Data Receptors, Cytoplasmic and Nuclear / chemistry Receptors, Cytoplasmic and Nuclear / genetics Receptors, Cytoplasmic and Nuclear / physiology Sequence Homology, Amino Acid
IF 9.889
Times Cited 82
Cellular slime molds G20748 S00009