| First Author | Langston AW | Year | 1997 |
| Journal | J Biol Chem | Volume | 272 |
| Issue | 4 | Pages | 2167-75 |
| PubMed ID | 8999919 | Mgi Jnum | J:38670 |
| Mgi Id | MGI:86052 | Doi | 10.1074/jbc.272.4.2167 |
| Citation | Langston AW, et al. (1997) Retinoic acid-responsive enhancers located 3' of the Hox A and Hox B homeobox gene clusters. Functional analysis. J Biol Chem 272(4):2167-75 |
| abstractText | Homeobox genes control the spatial identity and differentiation of tissues in the developing vertebrate embryo. Retinoids are signaling molecules involved in the regulation of Hox genes. We previously identified a 3' enhancer called the RAIDR5, which contained a DR5 retinoic acid response element (RARE) and was responsible for the retinoic acid (RA)-associated expression of the murine Hoxa-1 gene in teratocarcinoma cells. We demonstrate that a similar enhancer, which contains a DR5 RARE, is located at a DNase I-hypersensitive site 3' of the murine Hoxb-1 gene. This enhancer, the Hoxb-1 RAIDR5, regulates the RA responsiveness of the Hoxb-1 gene and is different in location and sequence from the RA-regulated 3' Hoxb-1 enhancers previously described. Several DNA elements within the murine Hoxa-1 RA-inducible RAIDR5 enhancer, including the DR5 RARE, conserved element (CE) 1, and CE2, are conserved in the murine Hoxb-1 RAIDR5 enhancer, the human homolog of Hoxa-1, and in the chicken Hoxb-1 gene. Gel shifts show that the CE2 sequence TATTTACTCA binds an RA-inducible factor, while UV cross-linking indicates that a 170-kDa protein binds to this sequence. Thus, the Hoxa-1 and Hoxb-1 genes possess 3' enhancers with similar sequences through which their expression and responsiveness to endogenous retinoids are controlled. |
