3pin
Crystal structure of Mxr1 from Saccharomyces cerevisiae in complex with Trx2Crystal structure of Mxr1 from Saccharomyces cerevisiae in complex with Trx2
Structural highlights
FunctionTRX2_YEAST Participates as a hydrogen donor in redox reactions through the reversible oxidation of its active center dithiol to a disulfide, accompanied by the transfer of 2 electrons and 2 protons. It is involved in many cellular processes, including deoxyribonucleotide synthesis, repair of oxidatively damaged proteins, protein folding, sulfur metabolism, and redox homeostasis. Thioredoxin-dependent enzymes include phosphoadenosine-phosphosulfate reductase MET16, alkyl-hydroperoxide reductase DOT5, thioredoxin peroxidases TSA1 and TSA2, alkyl hydroperoxide reductase AHP1, and peroxiredoxin HYR1. Thioredoxin is also involved in protection against reducing stress. As part of the LMA1 complex, it is involved in the facilitation of vesicle fusion such as homotypic vacuole and ER-derived COPII vesicle fusion with the Golgi. This activity does not require the redox mechanism. Through its capacity to inactivate the stress response transcription factor YAP1 and its regulator the hydroperoxide stress sensor HYR1, it is involved in feedback regulation of stress response gene expression upon oxidative stress.[1] [2] [3] [4] [5] [6] [7] [8] [9] [10] Publication Abstract from PubMedThe methionine S-sulfoxide reductase MsrA catalyzes the reduction of methionine sulfoxide, a ubiquitous reaction depending on the thioredoxin system. To investigate interactions between MsrA and thioredoxin (Trx), we determined the crystal structures of yeast MsrA/Mxr1 in their reduced, oxidized, and Trx2-complexed forms, at 2.03, 1.90, and 2.70 A, respectively. Comparative structure analysis revealed significant conformational changes of the three loops, which form a plastic "cushion" to harbor the electron donor Trx2. The flexible C-terminal loop enabled Mxr1 to access the methionine sulfoxide on various protein substrates. Moreover, the plasticity of the Trx binding site on Mxr1 provides structural insights into the recognition of diverse substrates by a universal catalytic motif of Trx. Structural plasticity of the thioredoxin recognition site of yeast methionine S-sulfoxide reductase Mxr1.,Ma XX, Guo PC, Shi WW, Luo M, Tan XF, Chen Y, Zhou CZ J Biol Chem. 2011 Apr 15;286(15):13430-7. Epub 2011 Feb 23. PMID:21345799[11] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
|
| ||||||||||||||||