Structural Mechanisms of Swi2/Snf2 Protein:DNA remodeller
Pr Karl-Peter HOPFNER
Ludwig-Maximilians-University Munich - Gene center & Dept. Biochemistry - MUNICH, Allemagne
mercredi 13 septembre 2017 - 11h00
- Auditorium, IGBMC
Invité(e) par Valérie LAMOUR
Swi2/Snf2 ATPases are molecular machines that remodel substrate DNA:protein complexes. Most prominently, Swi2/Snf2 chromatin remodeller alter the position and composition of nucleosomes on DNA in a genome wide manner and ensure the correct structural organisation and dynamic properties of chromatin. Swi2/Snf2 remodeller form a very large and diverse family, ranging from smaller single subunit enzymes to large multisubunit chromatin remodeller such as the INO80 complex. INO80/SWR1 family chromatin remodellers are complexes composed of >15 subunits and molecular masses exceeding 1 MDa. They have important roles in transcription, replication and DNA repair by exchanging the histone variants H2A and H2A.Z, as well as other emerging activities such as nucleosome positioning and sliding, but their mechanism, specificity and regulation is poorly understood . In addition, due to their size, flexibility and molecular complexity, megadalton chromatin remodeller are a formidable challenge for structural studies. Using two examples, the single subunit remodeller Mot1 and the INO80 complex, I will discuss recent progress and our current understanding of the targeting, regulation and chemo-mechanical mechanism of remodellers with a focus on integrative structural analysis.