Location: Healthy Processed Foods ResearchTitle: High resolution crystal structure of human Dim2/TXNL4B Author
Submitted to: Acta Crystallographica Section F: Structural Biology and Crystallization Communications
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/10/2013
Publication Date: 2/22/2013
Citation: Jin, T., Guo, F., Wang, Y., Zhang, Y. 2013. High resolution crystal structure of human Dim2/TXNL4B. Acta Crystallographica Section F: Structural Biology and Crystallization Communications. 69(Pt 3):223-227. DOI: 10.1107/S1744309113000973. Interpretive Summary: At present, it is not clear why a subpopulation is allergic to foods. It is also why a few of the thousands of proteins in a food source causes allergic reaction. Searching for genetic factors that might shed light on the mechanisms of food allergy has not brought any hope for finding a cure for food allergies in the near future. It is reported that in the case of autoimmune and severe food allergy as a variant of the immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome, pre-mRNA splicing defect may be one of the problem. This study reported a high-resolution crystal structure of human thioredoxin like protein 4B (TXNL4B). Structural information indicated that a region of TXNL4B previously reported as responsible for its interaction with prp6 (a central component of the pre-mRNA splicing machinery) includes a part of the B-sheet core of the protein and is unlikely to facilitate the interaction.
Technical Abstract: TXNL4A (thioredoxin like 4A) is an essential protein conserved from yeast to human and is a component of the pre-mRNA splicing machinery. TXNL4B was identified as a TXNL4 family protein that also interacts with prp6, an integral component of the U4/U6•U5 tri-snRNP complex, and was shown to function in pre-mRNA splicing. A crystal structure of TXNL4B was determined at 1.33 Å resolution and refined to an Rwork of 14.7% and an Rfree of 19.7% with one native dimer of TXNL4B in the asymmetric unit. Residues 1-33 of TXNL4A were previously reported to be responsible for its interaction with prp6. This region, however, extends to the B-sheet core of the thioredoxin fold structure of TXNL4B. This suggests that interpretation of previously reported GST pull-down results without considering structure and stability of TXNL4B is debatable.