title: Localizing the lipid products of PI3Kγ in neutrophils.
abstract: Class I phosphoinositide 3-kinases (PI3Ks) are important regulators of neutrophil migration in response to a range of chemoattractants. Their primary lipid products PtdIns(3,4,5)P3 and PtdIns(3,4)P2 preferentially accumulate near to the leading edge of migrating cells and are thought to act as an important cue organizing molecular and morphological polarization. We have investigated the distribution and accumulation of these lipids independently in mouse neutrophils using eGFP-PH reportersand electron microscopy (EM). We found that authentic mouse neutrophils rapidly polarized their Class I PI3K signalling, as read-out by eGFP-PH reporters, both at the up-gradient leading edge in response to local stimulation with fMLP as well as spontaneously and randomly in response to uniform stimulation. EM studies revealed these events occurred at the plasma membrane, were dominated by accumulation of PtdIns(3,4,5)P3, but not PtdIns(3,4)P2, and were dependent on PI3Kγ and its upstream activation by both Ras and Gβγs.
authors.affiliation: The Signalling Department, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom.
authors.forename: Laura
authors.initials: L
authors.lastname: Norton
authors.affiliation: Division of Molecular Physiology, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK; Division of Cell Biology and Immunology, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Lindsay
authors.affiliation: The Signalling Department, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom.
authors.forename: Arnaud
authors.initials: A
authors.lastname: Deladeriere
authors.affiliation: The Signalling Department, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom.
authors.forename: Tamara
authors.initials: T
authors.lastname: Chessa
authors.affiliation: Laboratoire de Pharmacologie et Toxicologie, INRA UR66, Toulouse, France.
authors.forename: Hervé
authors.initials: H
authors.lastname: Guillou
authors.affiliation: The Signalling Department, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom.
authors.forename: Sabine
authors.initials: S
authors.lastname: Suire
authors.affiliation: Division of Cell Biology and Immunology, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK.
authors.forename: John
authors.initials: J
authors.lastname: Lucocq
authors.affiliation: The Imaging Facility, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Walker
authors.affiliation: The Bioinformatics Group, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, UK.
authors.forename: Simon
authors.initials: S
authors.lastname: Andrews
authors.affiliation: The Bioinformatics Group, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, UK.
authors.forename: Anne
authors.initials: A
authors.lastname: Segonds-Pichon
authors.affiliation: UCB, Allée de la Recherche, 60 1070 Brussels, Belgium.
authors.forename: Oliver
authors.initials: O
authors.lastname: Rausch
authors.affiliation: Developmental and Molecular Pathways, Novartis Institutes for BioMedical Research, 250 Massachusetts Avenue, Cambridge, MA 02139, USA.
authors.forename: Peter
authors.initials: P
authors.lastname: Finan
authors.affiliation: Department of Pathology and Immunology, Akita University School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan.
authors.forename: Takehiko
authors.initials: T
authors.lastname: Sasaki
authors.affiliation: Warwick Systems Biology Centre, University of Warwick, UK.
authors.forename: Cheng-Jin
authors.initials: CJ
authors.lastname: Du
authors.affiliation: Warwick Systems Biology Centre, University of Warwick, UK.
authors.forename: Till
authors.initials: T
authors.lastname: Bretschneider
authors.affiliation: The Signalling Department, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom.
authors.forename: G John
authors.initials: GJ
authors.lastname: Ferguson
authors.affiliation: The Signalling Department, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom.
authors.forename: Phillip T
authors.initials: PT
authors.lastname: Hawkins
authors.affiliation: The Signalling Department, The Babraham Institute, The Babraham Research Campus, Cambridge, CB22 3AT, United Kingdom. Electronic address: len.stephens@bbsrc.ac.uk.
authors.forename: Len
authors.initials: L
authors.lastname: Stephens
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D058544:Class Ib Phosphatidylinositol 3-Kinase / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D009504:Neutrophils / Q000201:enzymology* / Q000378:metabolism; D018129:Phosphatidylinositol Phosphates / Q000378:metabolism*; D021381:Protein Transport
chemical_list: D018129:Phosphatidylinositol Phosphates; C060974:phosphatidylinositol 3,4,5-triphosphate; C060980:phosphatidylinositol 3,4-diphosphate; D058544:Class Ib Phosphatidylinositol 3-Kinase; C546764:Pik3cg protein, mouse
keywords: Neutrophil; PI3K; Polarization