Characterization and functional studies of human thioredoxin-like 1 (Txl-1) protein

Thioredoxins (Trx) are small redox proteins that regulate many different cellular processes such as apoptosis, transcription factor DNA binding activity, cell growth, differentiation and cancer or oxidative stress. During the last few years our group has been engaged in the search for novel members of this family of proteins which has resulted in the discovery of several new thioredoxins, both ubiquitous and tissue-specific. One of these novel proteins, named Txl-1 (stands for thioredoxin-like 1), has been shown to be present in all human tissues screened and has a cytosolic localization. Despite having homologues in lower eukaryotes such as the worm C. elegans and the fruitfly Drosophila melanogaster there is no clue about its function.
This project aims to decipher the physiological role of Txl-1 in eukaryotic cells to provide relevant information about the significance of this protein in the general context of thioredoxins. With this purpose, we will first produce recombinant Txl-1 protein to purify specific polyclonal antibodies that will allow future analysis. In parallel we will address the subcellular localization of the enzyme by Green-Fluorescent Protein analysis. Another important part of the project will consist on the isolation and characterization of stably transfected human cells overexpressing Txl-1. This approach will allow us to study the role of Txl-1 in normal cellular metabolism as well as in other pathological situations such as oxidative stress or apoptosis where other thioredoxins have been shown to play important functions.