2024-03-28T08:38:08Zhttp://digital.csic.es/dspace-oai/requestoai:digital.csic.es:10261/475002019-02-20T12:30:55Zcom_10261_11773com_10261_1col_10261_11774
00925njm 22002777a 4500
dc
Jiménez, Alberto
author
Miranda-Vizuete, Antonio
author
2003-01-24
Thioredoxins comprise a growing family of proteins that function as general protein-disulfide reductases and are maintained in their reduced active form by the flavoenzyme thioredoxin reductase. Human Trx-1 is mainly a cytosolic protein, although it has been shown to translocate into the nucleus upon certain stimuli and can also be secreted. We report here the expression and characterization of delta3Trx-1, a splicing variant of human Trx-1, lacking exon 3, which spans from residues 44 to 63 in the wild-type protein. Structure-based prediction of this splicing form indicates that delta3Trx-1 lacks helix alpha2 and strand beta3, which are implicated in substrate positioning and three-dimensional stabilization of the active site residues. Recombinant human delta3Trx-1 is recognized by polyclonal antibodies raised against full-length human Trx-1. However, delta3Trx-1 retains no enzymatic activity either with DTT or thioredoxin reductase and NADPH as reducing systems. Delta3Trx-1 competes with full-length Trx-1 for the interaction with thioredoxin reductase. The absence of helix alpha2 and strand beta3 in delta3Trx-1 is consistent with the lack of enzymatic activity and its potential dominant negative properties.
Protein Expression and Purification 27(2): 319-324 (2003)
1046-5928
PMID: 12597892
http://hdl.handle.net/10261/47500
10.1016/S1046-5928(02)00607-1
1096-0279
Cytosol
Dithiothreitol
Electrophoresis
Exons
Membrane proteins
Thioredoxin
Tumor cells
Purification and characterization of Δ3Trx-1, a splicing variant of human thioredoxin-1 lacking exon 3