Partenaires

CNRS


Rechercher


Accueil > Publications > Recherche par années > Années 1990 > 1995

Albert, AC ; Leng, M ; Rahmouni, AR

The size of the topological domain modulates the b-z transition of a (tg)(n) containing repeat

Journal of Biomolecular Structure & Dynamics 13 (1) 47-56

par Administrateur - publié le

Abstract :

Under negative superhelical stress,long(TG), containing repeats experience a stepwise multiple B-Z transitions. We have investigated the effect of the plasmid size on this transitional behavior. A 66-bp (TG)(n) containing repeat from the 5’-untranscribed region of mouse ribosomal DNA was inserted in a 3-kb, a 6.5-kb and a 12.5-kb plasmids and its supercoil-driven B-Z transition was followed by OsO4 probing of topoisomer-populations. Our results show a clear correlation between the size of the topological domain and the extent of the region that converts cooperatively into Z-DNA at the initial transition.