title: Two poles and a compass.
abstract: Rho GTPases control fundamental aspects of neutrophil chemotaxis: establishment of front and back and orientation toward the chemoattractant. Two reports in this issue show that activated Cdc42 at the leading edge helps orient the cell's axis in a signaling complex with G beta gamma, PAK1, and PIX alpha; while Rho, activated via G alpha 13, mediates formation of the uropod, which then interacts by mutual negative feedback with the front to reinforce polarization (Li et al., 2003 [this issue of Cell]; Xu et al., [this issue of Cell]).
authors.affiliation: Section of Cell and Developmental Biology, Division of Biological Sciences and Center for Molecular Genetics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
authors.forename: Ruedi
authors.initials: R
authors.lastname: Meili
authors.forename: Richard A
authors.initials: RA
authors.lastname: Firtel
mesh_terms: D018797:Cell Cycle Proteins / Q000378:metabolism; D016764:Cell Polarity / Q000502:physiology*; D002634:Chemotaxis, Leukocyte; D003599:Cytoskeleton / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D044365:GTP-Binding Protein alpha Subunits, G12-G13; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism; D006801:Humans; D009504:Neutrophils / Q000166:cytology / Q000201:enzymology / Q000502:physiology*; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D064067:Rho Guanine Nucleotide Exchange Factors; D015398:Signal Transduction; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism*; D054462:p21-Activated Kinases; D020741:rho GTP-Binding Proteins / Q000378:metabolism*; D020742:rhoA GTP-Binding Protein / Q000378:metabolism
chemical_list: D018797:Cell Cycle Proteins; D004268:DNA-Binding Proteins; D044365:GTP-Binding Protein alpha Subunits, G12-G13; D020662:Guanine Nucleotide Exchange Factors; D019869:Phosphatidylinositol 3-Kinases; D017346:Protein Serine-Threonine Kinases; D064067:Rho Guanine Nucleotide Exchange Factors; D020764:cdc42 GTP-Binding Protein; D054462:p21-Activated Kinases; D020741:rho GTP-Binding Proteins; D020742:rhoA GTP-Binding Protein; C515903:PAK1 protein, human