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TZID:Europe/Paris
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BEGIN:VEVENT
UID:1-205@lptms.universite-paris-saclay.fr
DTSTART:20140117T140000Z
DTEND:20140117T150000Z
DTSTAMP:20140114T180109Z
URL:http://www.lptms.universite-paris-saclay.fr/seminars/physics-biology-i
 nterface-seminar-alexis-gautreau/
SUMMARY:Physics-Biology interface seminar: Alexis Gautreau - Moyen Amphi\, 
 Building 510\, Université Paris-Saclay Orsay - 17 Jan 14 14:00
DESCRIPTION:Inhibitory signalling to the Arp2/3 complex steers cell migrati
 on\nAlexis Gautreau (LEBS - Gif-sur-Yvette)\nCell migration requires the g
 eneration of branched actin networks that power the protrusion of the plas
 ma membrane in lamellipodia. The Arp2/3 complex is the molecular machine t
 hat nucleates these branched actin networks. This machine is activated at 
 the leading edge of migrating cells by the WAVE complex. The WAVE complex 
 is itself directly activated by the small GTPase Rac\, which induces lamel
 lipodia. However\, how cells regulate the directionality of migration is p
 oorly understood. Here we identify a novel protein that inhibits the Arp2/
 3 complex in vitro\, Arpin\, and show that Rac signalling recruits and act
 ivates Arpin at the lamellipodial tip\, like WAVE. Consistently\, upon dep
 letion of the inhibitory Arpin\, lamellipodia protrude faster and cells mi
 grate faster. A major role of this inhibitory circuit\, however\, is to co
 ntrol directional persistence of migration. Indeed\, Arpin depletion in bo
 th mammalian cells and Dictyostelium discoideum amoeba resulted in straigh
 ter trajectories\, whereas Arpin microinjection in fish keratocytes\, one 
 of the most persistent systems of cell migration\, induced these cells to 
 turn. The coexistence of the Rac-Arpin-Arp2/3 inhibitory circuit with the 
 Rac-WAVE-Arp2/3 activatory circuit can account for this conserved role of 
 Arpin in steering cell migration. Loss of this inhibitory circuit promotes
  exploratory behaviors and might commit carcinoma cells to the invasive st
 ate.\n
LOCATION:Moyen Amphi\, Building 510\, Université Paris-Saclay Orsay\, 15 R
 ue Georges Clemenceau\, orsay\, France
GEO:48.698187;2.181768
X-APPLE-STRUCTURED-LOCATION;VALUE=URI;X-ADDRESS=15 Rue Georges Clemenceau\,
  orsay\, France;X-APPLE-RADIUS=100;X-TITLE=Moyen Amphi\, Building 510\, Un
 iversité Paris-Saclay Orsay:geo:48.698187,2.181768
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