Structure and Function of the Yeast Chromosomal Replicator Ars1 (Plasmid)

Autonomously Replicating Sequence 1 (ARS1) is a cis acting DNA sequence that allows the extra-chromosomal maintenance of plasmids in the yeast Saccharomyces cerevisiae. In order to define the functional domains of ARS1 and determine its role in plasmid maintenance, I have performed in vitro mutagenesis in the region containing ARS1 and measured their effects on Ars activity using the parameters of high-frequency transformation, colony morphology, copy number, and stability in both high- and low-copy plasmids. The mutagenesis was in the form of insertions (10-4200 base pairs) and deletions. My results indicate that the consensus sequence found in all ARS elements is essential for Ars function and that one flanking region but not the other is important for maximizing Ars activity. The effects of the mutations on plasmid maintenance include altered colony morphology due to severe plasmid loss, reduced copy number, a reduction in the percent of plasmid-bearing cells using high-copy plasmids, and an increased rate of 1:0 (simple loss) using low-copy centromere containing plasmids. These results indicate that the role ARS1 plays in plasmid maintenance is concerned with the replication and/or localization of the plasmid and not its segregation.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Microbiology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2014

Author dc:creator

• Strich, Randy Stephen

• Biology, Molecular

Identifier

(UMI)AAI8701627

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/71180