Display Settings:


Send to:

Choose Destination
J Mol Biol. 2006 Dec 15;364(5):1034-47. Epub 2006 Oct 3.

Luman, a new partner of HIV-1 TMgp41, interferes with Tat-mediated transcription of the HIV-1 LTR.

Author information

  • 1Institut Cochin, Département Maladies Infectieuses, Paris F-75014, France.


In our search for new partners of the HIV-1 envelope glycoprotein (Env), we found that the cytoplasmic domain of the TMgp41 (TMgp41 CD) subunit of HIV-1 Env interacted with Luman, a transcription factor of the CREB/ATF family. Luman is anchored in the endoplasmic reticulum membrane and subjected to activation by regulated intramembrane proteolysis (RIP). The RIP process permits the release of the activated amino-terminal fragment of Luman into the cytoplasm, and its import into the nucleus. Here, we demonstrate that interaction between the TMgp41 CD and Luman requires a region encompassing the b-Zip and TM domains of Luman and decreases the stability of this factor. Moreover, we found that overexpression of a constitutively active form of Luman in cells transfected with HXB2R HIV-1 provirus decreased the intracellular expression of Gag and Env and led to a decrease in virion release. This negative effect of activated Luman on HIV-1 production was correlated to the inhibition of Tat transactivation of the HIV-1 LTR, which might be related to an interaction of activated Luman with Tat. Altogether, these results show that Luman acts as a partner of two major HIV-1 proteins: the TMgp41 Env subunit and Tat. The interaction between the TMgp41 subunit of Env and Luman affects the stability of the full-length Luman protein, the precursor of the activated, nuclear form of Luman, which acts negatively on Tat-mediated HIV-1 transactivation.

[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Icon for Elsevier Science
    Loading ...
    Write to the Help Desk