Dr. Marcus Cebula - Institutet för miljömedicin, Karolinska Institutet

Abstract

Reversible oxidative modifications of redox sensitive protein thiols have emerged as a major posttranslational mechanism modulating the function of the respective proteins. These modifications can be reversed by redox catalysts of which the thioredoxin and glutathione systems form the most prominent.

One particular group of redox sensitive proteins are transcription factors that are able to regulate the rapid transcription of genes. Many of these are functionally intertwined whereby their concerted action determines the final outcome of cellular responses to different redox perturbing conditions. But so far the knowledge of how intracellular redox signaling events are coordinated onto specific transcriptional responses is yet only rudimentary at best. In order to better understand these processes and thus the cellular response we developed a fluorescence-based reporter plasmid (named pTRAF) that can be used to simultaneously study the behaviour of any three transcription factors with single cell resolution.

Within the development and initial characterization of pTRAF we focused on three medically important transcription factors Nrf2, HIF and NFκB, which are involved in many pathological conditions correlated to oxidative stress, hypoxia and inflammation. These three transcription factors display highly complex regulatory patterns, all being affected by redox regulation and displaying clear overlaps in their responses. We believe that pTRAF-based analyses will help to provide better insights into their regulation and thus have a major impact towards the understanding and treatment of different pathological conditions including cancer as well as neurodegenerative and vascular diseases.