2k27 is a 1 chain structure with sequence from Homo sapiens. Full experimental information is available from OCA. For a guided tour on the structure components use FirstGlance.
[PAX8_HUMAN] Defects in PAX8 are the cause of congenital hypothyroidism non-goitrous type 2 (CHNG2) [MIM:218700]. CHNG2 is a disease characterized by thyroid dysgenesis, the most frequent cause of congenital hypothyroidism, accounting for 85% of case. The thyroid gland can be completely absent (athyreosis), ectopically located and/or severely hypoplastic. Ectopic thyroid gland is the most frequent malformation, with thyroid tissue being found most often at the base of the tongue.[1][2][3]
Function
[PAX8_HUMAN] Transcription factor for the thyroid-specific expression of the genes exclusively expressed in the thyroid cell type, maintaining the functional differentiation of such cells.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Pax-8 is a transcription factor belonging to the PAX genes superfamily and its crucial role has been proven both in embryo and in the adult organism. Pax-8 activity is regulated via a redox-based mechanism centered on the glutathionylation of specific cysteines in the N-terminal region (Cys45 and Cys57). These residues belong to a highly evolutionary conserved DNA binding site: the Paired Box (Prd) domain. Crystallographic protein-DNA complexes of the homologues Pax-6 and Pax-5 showed a bipartite Prd domain consisting of two helix-turn-helix (HTH) motifs separated by an extended linker region. Here, by means of nuclear magnetic resonance, we show for the first time that the HTH motifs are largely defined in the unbound Pax-8 Prd domain. Our findings contrast with previous induced fit models, in which Pax-8 is supposed to largely fold upon DNA binding. Importantly, our data provide the structural basis for the enhanced chemical reactivity of residues Cys45 and Cys57 and explain clinical missense mutations that are not obviously related to the DNA binding interface of the paired box domain. Finally, sequence conservation suggests that our findings could be a general feature of the Pax family transcription factors.
The solution structure of DNA-free Pax-8 paired box domain accounts for redox regulation of transcriptional activity in the pax protein family.,Codutti L, van Ingen H, Vascotto C, Fogolari F, Corazza A, Tell G, Quadrifoglio F, Viglino P, Boelens R, Esposito G J Biol Chem. 2008 Nov 28;283(48):33321-8. Epub 2008 Sep 30. PMID:18829450[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
↑Macchia PE, Lapi P, Krude H, Pirro MT, Missero C, Chiovato L, Souabni A, Baserga M, Tassi V, Pinchera A, Fenzi G, Gruters A, Busslinger M, Di Lauro R. PAX8 mutations associated with congenital hypothyroidism caused by thyroid dysgenesis. Nat Genet. 1998 May;19(1):83-6. PMID:9590296 doi:10.1038/ng0598-83
↑Vilain C, Rydlewski C, Duprez L, Heinrichs C, Abramowicz M, Malvaux P, Renneboog B, Parma J, Costagliola S, Vassart G. Autosomal dominant transmission of congenital thyroid hypoplasia due to loss-of-function mutation of PAX8. J Clin Endocrinol Metab. 2001 Jan;86(1):234-8. PMID:11232006
↑Congdon T, Nguyen LQ, Nogueira CR, Habiby RL, Medeiros-Neto G, Kopp P. A novel mutation (Q40P) in PAX8 associated with congenital hypothyroidism and thyroid hypoplasia: evidence for phenotypic variability in mother and child. J Clin Endocrinol Metab. 2001 Aug;86(8):3962-7. PMID:11502839
↑Codutti L, van Ingen H, Vascotto C, Fogolari F, Corazza A, Tell G, Quadrifoglio F, Viglino P, Boelens R, Esposito G. The solution structure of DNA-free Pax-8 paired box domain accounts for redox regulation of transcriptional activity in the pax protein family. J Biol Chem. 2008 Nov 28;283(48):33321-8. Epub 2008 Sep 30. PMID:18829450 doi:10.1074/jbc.M805717200
