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TZID:Europe/Paris
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UID:0-1064@lptms.universite-paris-saclay.fr
DTSTART;TZID=Europe/Paris:20251212T110000
DTEND;TZID=Europe/Paris:20251212T120000
DTSTAMP:20251210T134253Z
URL:http://www.lptms.universite-paris-saclay.fr/seminars/physics-biology-i
 nterface-seminar-valerio-sorichetti/
SUMMARY:Physics-Biology Interface seminar: Valerio Sorichetti - Salle des s
 éminaires du FAST et du LPTMS\, bâtiment Pascal n°530 - 12 Déc 25 11:0
 0
DESCRIPTION:Charged for attraction: How biomolecular condensates pull chrom
 osomes together\nValerio Sorichetti (IST Austria)\nThe coacervation of cha
 rged polymers is an important driver for the formation of biomolecular con
 densates. Recent experiments suggest that this mechanism also controls the
  clustering of eukaryotic chromosomes during the late stages of cell divis
 ion [1\,2]. In this process\, inter-chromosome attraction is driven by the
  condensation of cytoplasmic RNA and Ki-67\, a charged intrinsically disor
 dered protein that coats the chromosomes as a brush. Attraction between ch
 romosomes has been shown to be specifically promoted by a localized charge
 d patch on Ki-67\, although the physical mechanism remains unclear [2]. To
  elucidate this process\, we combine coarse-grained simulations and analyt
 ical theory to study the RNA-mediated interaction between charged polymer 
 brushes on the chromosome surfaces [3]. We find that the charged patch on 
 Ki-67 leads to inter-chromosome attraction via RNA bridging between the tw
 o brushes\, whereby the RNA preferentially interacts with the charged patc
 hes\, leading to stable\, long-range forces. By contrast\, if the brush is
  uniformly charged\, bridging is basically absent due to complete adsorpti
 on of RNA onto the brush. Moreover\, the RNA dynamics becomes caged in pre
 sence of the charged patch\, while remaining diffusive when the charge is 
 uniform. Our findings suggest that cells could control the forces exerted 
 by biomolecular condensates by adjusting the way charges are distributed o
 n proteins\, providing a potential strategy for regulating biological orga
 nization.\n\n 	S. Cuylen-Haering\, M. Petrovic\, A. Hernandez-Armendariz\,
  M. W. Schneider\, M. Samwer\, C. Blaukopf\, L. J. Holt\, and D. W. Gerlic
 h\, Nature 587\, 285 (2020)\n 	A. Hernandez-Armendariz\, V. Sorichetti\, Y
 . Hayashi\, Z. Koskova\, A. Brunner\, J. Ellenberg\, A. Šarić\, and S. C
 uylen-Haering\, Molecular Cell 84\, 3254 (2024).\n 	V. Sorichetti\, P. Rob
 in\, I. Palaia\, A. Hernandez-Armendariz\, S. Cuylen-Haering\, A. Šarić\
 , Charge distribution of coating brush drives inter-chromosome attraction\
 , PRX Life 3\, 033010 (2025).\n\n\nThe seminar will be broadcasted over Zo
 om:\nhttps://cnrs.zoom.us/j/91724933601?pwd=Ip6PR9IZO9SGoXIpLBC9qwZTaIlCEz
 .1\nID de réunion: 917 2493 3601\nCode secret: 15aMuZ
CATEGORIES:physbio,seminars
LOCATION:Salle des séminaires du FAST et du LPTMS\, bâtiment Pascal n°53
 0\, rue André Riviere\, Orsay\, 91405\, France
X-APPLE-STRUCTURED-LOCATION;VALUE=URI;X-ADDRESS=rue André Riviere\, Orsay\
 , 91405\, France;X-APPLE-RADIUS=100;X-TITLE=Salle des séminaires du FAST 
 et du LPTMS\, bâtiment Pascal n°530:geo:0,0
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TZID:Europe/Paris
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BEGIN:STANDARD
DTSTART:20251026T020000
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TZOFFSETTO:+0100
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