title: Copy number and the stability of 2-micron circle-based artificial plasmids of Saccharomyces cerevisiae.
abstract: The copy number and stability of artificial 2-micron circle-based plasmids have been accurately measured in [Cir+] and [Cir0] strains of Saccharomyces cerevisiae. We conclude that (i) instability and copy number vary greatly from plasmid to plasmid; (ii) instability and copy number are negatively correlated--that is, high copy number is associated with low instability; (iii) it is difficult to reconcile this variability with a strict and direct system of copy number control; (iv) instabilities are much higher than expected from random partition and the observed copy numbers: this may imply partition which is less efficient than random. Even so, (v) the partitioning of 2-micron circle-like plasmids is more efficient than that of ARS-based plasmids, which hints at the existence of a system for the (inefficient) distribution of 2-micron circles.
mesh_terms: D002678:Chimera; D004271:DNA, Fungal / Q000235:genetics; D014644:Genetic Variation; D007700:Kinetics; D010957:Plasmids; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D014170:Transformation, Genetic
chemical_list: D004271:DNA, Fungal