Electronic Theses and Dissertations

Date of Award

1-1-2019

Document Type

Thesis

Degree Name

M.S. in Chemistry

First Advisor

Randy M. Wadkins

Second Advisor

Saumen Chakraborty

School

University of Mississippi

Relational Format

dissertation/thesis

Abstract

Alternative DNA structures are likely to form from Watson-Crick B-form DNA when antitumor drug known to bind DNA loops -- can affect the iM structure. Our results demonstrate as an i-motif (iM). While both structures are known to exist in vivo they are energetically uphill can utilize intercalating cytosine-cytosine base pairing to form a four-stranded structure known controlled by alternative DNA structures like G4s and iMs. especially during processes that involve superhelical duress. A guanosine rich strand can form a facilitate their stabilization. In this report we present data on how 7-aminoactinomycin D -- an formation. Earlier it was believed that iMs required slightly acidic conditions (pH ≤ 6) for four-stranded structure known as a G-quadruplex (G4). The complimentary cytosine rich strand from double strand DNA (dsDNA) meaning that additional factors are needed to facilitate their of ~7. Additionally loop regions of iMs have been implicated in their thermal and pH-dependent shift the pKa of the iM (the pH at which 50% of the iM is folded) nearer to the physiological pH small molecules may be a promising way to therapeutically regulate expression of genes stability. Small molecules such as polyamines and larger molecules like proteins can interact structure stabilization. However crowding agents like polyethylene glycols and dextrans can that a small molecule antitumor drug can stabilize or destabilize iMs by simultaneously changing there is an asymmetric distribution of guanosine and cytosine on opposite DNA strands thermodynamic properties including Tm pKa and ΔG°37 °C. Our results suggest that the use of with iMs by binding to their loops suggesting that additional biochemical factors may also facilitate their stabilization. In this report, we present data on how 7-aminoactinomycin D -- an antitumor drug known to bind DNA loops -- can affect the iM structure. Our results demonstrate that a small molecule antitumor drug can stabilize or destabilize iMs by simultaneously changing thermodynamic properties including Tm, pKa, and ΔG°37 °C. Our results suggest that the use of small molecules may be a promising way to therapeutically regulate expression of genes controlled by alternative DNA structures like G4s and iMs.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.