Date of Award:

9-2016

Document Type:

Dissertation

Degree Name:

Doctor of Philosophy (PhD)

Department:

Chemistry and Biochemistry

Advisor/Chair:

Joan M. Hevel

Abstract

Protein arginine methylation is a posttranslational modification catalyzed by the family of proteins known as the protein arginine methyltransferases (PRMTs). Thousands of methylated arginines have been found in mammalian cells. Many targets of arginine regulation are involved in important cellular processes like transcription, RNA transport and processing, translation, cellular signaling, and DNA repair. Since PRMT dysregulation has been linked to a variety of disease states, understanding how the activity of the PRMTs is regulated is of paramount importance. PRMT1 is the predominant PRMT, responsible for about 85% of all arginine methylation in cells, but very little is known about how PRMT1 is regulated. Although a few methods to regulate PRMT1 activity have been reported, the details of interaction and regulatory mechanisms remain largely unknown.

To better understand how PRMT1 is able to bind its substrates and how PRMT1 activity is regulated, we followed a mechanistic and structural biology approach to better understand how PRMT1 interacts with its substrates and protein regulators. In this study the regulation of Hmt1 methyltransferase activity by the Air1 and Air2 proteins was analyzed and only one was determined to affect Hmt1 activity. The posttranslational phosphorylation of Hmt1 had also been reported to affect Hmt1 activity in vivo and our preliminary studies suggest that additional factors may help influence the regulatory effect of phosphorylation. Lastly, we report a new method of PRMT regulation through the reversible oxidation of key PRMT1 cysteine residues. We are also able to show that this regulation occurs in cells and affects several PRMT isoforms.

Checksum

fe05475f46c8f201c64ca1a50b43c16d

Available for download on Wednesday, September 01, 2021

Included in

Biochemistry Commons

Share

COinS