| First Author | Bieniasz PD | Year | 1998 |
| Journal | EMBO J | Volume | 17 |
| Issue | 23 | Pages | 7056-65 |
| PubMed ID | 9843510 | Mgi Jnum | J:51512 |
| Mgi Id | MGI:1316844 | Doi | 10.1093/emboj/17.23.7056 |
| Citation | Bieniasz PD, et al. (1998) Recruitment of a protein complex containing Tat and cyclin T1 to TAR governs the species specificity of HIV-1 Tat. EMBO J 17(23):7056-65 |
| abstractText | Human cyclin T1 (hCycT1), a major subunit of the essential elongation factor P-TEFb, has been proposed to act as a cofactor for human immunodeficiency virus type 1 (HIV-1) Tat. Here, we show that murine cyclin T1 (mCycT1) binds the activation domain of HIV-1 Tat but, unlike hCycT1, cannot mediate Tat function because it cannot be recruited efficiently to TAR. In fact, overexpression of mCycT1, but not hCycT1, specifically inhibits Tat-TAR function in human cells. This discordant phenotype results from a single amino acid difference between hCycT1 and mCycT1, a tyrosine in place of a cysteine at residue 261. These data indicate that the ability of Tat to recruit CycT1/P-TEFb to TAR determines the species restriction of HIV-1 Tat function in murine cells and therefore demonstrate that this recruitment is a critical function of the Tat protein. |
