| First Author | Reynaud C | Year | 2000 |
| Journal | J Biol Chem | Volume | 275 |
| Issue | 43 | Pages | 33962-8 |
| PubMed ID | 10940294 | Mgi Jnum | J:85778 |
| Mgi Id | MGI:2676550 | Doi | 10.1074/jbc.M000465200 |
| Citation | Reynaud C, et al. (2000) The PDZ protein TIP-1 interacts with the Rho effector rhotekin and is involved in Rho signaling to the serum response element. J Biol Chem 275(43):33962-8 |
| abstractText | The human T-cell lymphotrophic virus, type 1 Tax protein can interact via its C terminus with various proteins including a PDZ domain. In this work, one of them, TIP-1, is characterized as a cytoplasmic 14-kDa protein mainly corresponding to one PDZ domain. A two-hybrid screen performed with TIP-1 as bait showed that it interacts with the human homologue of rhotekin that was previously identified in mice as a Rho effector. Both human and mouse rhotekins exhibit at their C termini the sequence QSPV-COOH that matches the X(S/T)XV-COOH consensus known for proteins recognizing PDZ domains. Mutation of the serine and valine residues to alanine impairs interaction of rhotekin with TIP-1. Transient expression experiments with a reporter construct including the c-Fos serum response element (SRE) showed that coexpression of TIP-1 with the constitutively active RhoA.V14 mutant and human rhotekin caused a strong activation of the SRE. A negative mutant of Rho, RhoA.N19, was unable to cooperate with TIP-1 and rhotekin. The positive effect of TIP-1 was also lost when the C terminus of rhotekin was mutated. These data show that the complex of active Rho with its effector rhotekin bound to TIP-1 produces in the cytoplasm a signal that triggers strong activation of the SRE. |
