AI Article Synopsis
- The ELL-containing Super Elongation Complex (SEC) is crucial for HIV-1 transactivation by the Tat protein.
- EAF1 and EAF2 are positive regulators associated with ELL, but they inhibit HIV-1 transcription by interfering with SEC function.
- Depleting EAF1/2 enhances SEC formation and occupancy on HIV-1 DNA, promoting Tat transactivation, indicating their role in regulating HIV-1 transcription dynamics.
Article Abstract
The ELL (ELL1 and ELL2)-containing Super Elongation Complex (SEC) is required for efficient HIV-1 transactivation by the viral-encoded Tat protein. EAF1 and EAF2 are ELL-associated factors and considered as positive regulators of ELL. However, their role in HIV-1 transcriptional control is unknown. In this study, we show that EAF1/2 inhibit the SEC-dependent and Tat-activated HIV-1 transcription. EAF1/2 are found to interact with the SEC components in an ELL1/2-dependent manner. Surprisingly, the depletion of EAF1/2 increases the SEC formation and occupancy on the HIV-1 proviral DNA, thereby stimulating Tat transactivation of HIV-1. Although EAF1/2 interact with members of the SEC in a ELL-dependent manner, this interaction competes with the binding of the scaffolding subunit AFF1 with ELL, thus reducing the SEC formation. Together, these data reveal how EAF1/2 regulate the SEC formation to control HIV-1 transcription.
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| http://dx.doi.org/10.1016/j.bbagrm.2020.194508 | DOI Listing |
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