Structural basis for ELL2 and AFF4 activation of HIV-1 proviral transcription.
Structural basis for ELL2 and AFF4 activation of HIV-1 proviral transcription.
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HIV-1原病毒转录的ELL2和AFF4激活的结构基础
DOI：
10.1038/ncomms14076
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发表时间：
2017-01-30
影响因子：
16.6
通讯作者：
Hurley JH
中科院分区：
文献类型：
--
作者：
Qi S;Li Z;Schulze-Gahmen U;Stjepanovic G;Zhou Q;Hurley JH
The intrinsically disordered scaffold proteins AFF1/4 and the transcription elongation factors ELL1/2 are core components of the super elongation complex required for HIV-1 proviral transcription. Here we report the 2.0-Å resolution crystal structure of the human ELL2 C-terminal domain bound to its 50-residue binding site on AFF4, the ELLBow. The ELL2 domain has the same arch-shaped fold as the tight junction protein occludin. The ELLBow consists of an N-terminal helix followed by an extended hairpin that we refer to as the elbow joint, and occupies most of the concave surface of ELL2. This surface is important for the ability of ELL2 to promote HIV-1 Tat-mediated proviral transcription. The AFF4–ELL2 interface is imperfectly packed, leaving a cavity suggestive of a potential binding site for transcription-promoting small molecules. The host super elongation complex (SEC) is hijacked by HIV-1 for viral transcription. Here the authors present the structure of RNA polymerase elongation factor ELL2 bound to the intrinsically disordered scaffold protein AFF4, identifying an ELL2 surface important for HIV-1 transcription.
