| First Author | Underhill DA | Year | 1995 |
| Journal | Proc Natl Acad Sci U S A | Volume | 92 |
| Issue | 9 | Pages | 3692-6 |
| PubMed ID | 7731966 | Mgi Jnum | J:25084 |
| Mgi Id | MGI:72797 | Doi | 10.1073/pnas.92.9.3692 |
| Citation | Underhill DA, et al. (1995) Analysis of the mouse Splotch-delayed mutation indicates that the Pax-3 paired domain can influence homeodomain DNA-binding activity. Proc Natl Acad Sci U S A 92(9):3692-6 |
| abstractText | The murine Pax-3 protein contains two DNA-binding domains, a paired domain and a homeodomain, and alterations in the Pax-3 gene are responsible for the neural tube defects observed in the Splotch (Sp) mouse mutant. Of five Sp alleles, Splotch-delayed (Spd) is the only one that encodes a full-length Pax-3 protein, containing a single glycine-to-arginine substitution within the paired domain. To better understand the consequence of this mutation on Pax-3 function, we have analyzed the DNA-binding properties of wild-type and Spd Pax-3, using oligonucleotides that bind primarily to the paired domain (e5) or exclusively to the homeodomain (P2). Wild-type Pax-3 was found to bind e5 in a specific manner. In contrast, the Spd mutation reduced binding of Pax-3 to e5 17-fold, revealing a defect in DNA binding by the paired domain. Surprisingly, the Spd mutation also drastically reduced the homeodomain-specific binding to P2 by 21-fold when compared with the wild-type protein. Interestingly, a deletion which removes the Spd mutation was found to restore P2-binding activity, suggesting that within the full-length Pax-3 protein, the paired domain and homeodomain may interact. We conclude, therefore, that the Spd mutation is phenotyically expressed in vitro by a defect in the DNA-binding properties of Pax-3. Furthermore, it is apparent that the paired domain and homeodomain of Pax-3 do not function as independent domains, since a mutation in the former impairs the DNA-binding activity of the latter. |
