Access Type

Open Access Embargo

Date of Award

January 2022

Degree Type

Dissertation

Degree Name

Ph.D.

Department

Chemistry

First Advisor

Young-Hoon Ahn

Abstract

Cell migration is vital in many physiological processes, such as wound repair and metastasis. Impaired cell migration in wound healing may result in chronic wounds, by which 6.7 million Americans are affected, and they suffer from bacterial infections, amputations, increased mortality, and depression. Reactive oxygen species (ROS) or hydrogen peroxide (H2O2) play an essential role as a second messenger in redox signaling. Evidence has been found that H2O2 takes part in regulating cell migration as well. A primary mechanism of ROS regulating redox signaling is oxidative protein modifications. Protein S-glutathionylation, one of the oxidative modifications, is the conjugation of glutathione tripeptide with protein cysteine via disulfide bond formation. Numerous examples such as LMW-PTP, MKP-1, and actin have demonstrated that glutathionylation of specific proteins can regulate protein structures and function in redox signaling modulating cell migration. Despite these proteins, it is expected that H2O2 can react with many other proteins to regulate migration. Identification of glutathionylated proteins with their cysteine sites of modification will assist in understanding the regulatory mechanisms of cell migration which may help to develop treatment strategies for chronic wounds and cancer metastasis. First, we have used proteomics, bioinformatics, and biological screening to develop an approach to discover novel glutathionylated proteins that regulated cell migration. We have found PP2Cα C314, NISCH C186, and ARHGEF7 C469/700 as potential cysteines that undergo glutathionylation to regulate cell migration. We confirmed that PP2Cα C314 glutathionylation increases cell migration via JNK and ERK signaling pathways. Secondly, we have demonstrated that p120 catenin C692 glutathionylation destabilizes E-cadherin, promoting E-cadherin degradation. Subsequently, E-cadherin degradation increases cell migration and invasion suggesting that p120 glutathionylation destabilizes adheren junctions. Lastly, using the DAAO/D-Ala system, we have established a controlled system for proteomic analysis of glutathionylation under the condition of cell migration.

Available for download on Thursday, January 08, 2026

Included in

Biochemistry Commons

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