BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//wp-events-plugin.com//6.4.7.2//EN
TZID:Europe/Paris
X-WR-TIMEZONE:Europe/Paris
BEGIN:VEVENT
UID:1-425@lptms.universite-paris-saclay.fr
DTSTART:20160607T110000Z
DTEND:20160607T120000Z
DTSTAMP:20160519T055044Z
URL:http://www.lptms.universite-paris-saclay.fr/seminars/seminaire-du-lptm
 s-purushottam-dixit/
SUMMARY:Séminaire du LPTMS: Purushottam Dixit - LPTMS\, salle 201\, 2ème 
 étage\, Bât 100\, Campus d'Orsay - 7 Juin 16 11:00
DESCRIPTION:Metastability transition in genome evolution and population str
 ucture of bacterial species\nPurushottam Dixit (Columbia University\, US)\
 nTwo processes govern diversification of bacterial genomes. While point mu
 tations always increase population diversity\, horizontal gene transfers a
 ct as a cohesive force at the population level. Currently\, a detailed qua
 ntitative understanding of how these two opposing forces shape bacterial e
 volution at the level of individual genes\, genomes\, and populations is l
 acking. In a theoretical model\, we identify two qualitatively distinct ph
 ases in the dynamics of genome evolution\, characterized by the second eig
 envalue of the Markov process describing evolution.  In the  divergent p
 hase the cohesion due to recombination is not sufficient to overcome mutat
 ional drift. As a consequence both individual genes and the entire genomes
  within the same species keep diverging from each other in the course of e
 volution.  At the population level\, transient clusters of sub-population
 s are continuously formed and dissolved. In contrast\, in the metastable p
 hase\,  the recombination has the upper hand.  In this phase\, genomes o
 f descendants of a pair of sister cells remain close to each other for lon
 g periods of time but eventually escape the pull of recombination and dive
 rge indefinitely.  The population of the entire species remains genetical
 ly cohesive and stable over time and does not fragment into sexually isola
 ted sub-populations. Real bacterial examples are discussed as well.
CATEGORIES:seminars
LOCATION:LPTMS\, salle 201\, 2ème étage\, Bât 100\, Campus d'Orsay\, 15 
 Rue Georges Clemenceau\, Orsay\, 91405\, France
GEO:48.698185;2.181768
X-APPLE-STRUCTURED-LOCATION;VALUE=URI;X-ADDRESS=15 Rue Georges Clemenceau\,
  Orsay\, 91405\, France;X-APPLE-RADIUS=100;X-TITLE=LPTMS\, salle 201\, 2è
 me étage\, Bât 100\, Campus d'Orsay:geo:48.698185,2.181768
END:VEVENT
END:VCALENDAR