Activation of HTLV-I transcription in the presence of Tax is independent of the acetylation of CREB-2 (ATF-4).

We have previously demonstrated that the bZIP transcription factor CREB-2, also called ATF-4, trans-activates, in association with the viral protein Tax, the human T-cell leukemia virus type I (HTLV-I) promoter. In this study, we have examined whether CREB-2 acetylation affects transcriptional activation mediated by Tax. We present evidence that CREB-2 is acetylated in vitro and in vivo. CREB-2 is acetylated in two regions: the basic domain of the bZIP (from amino acid residue 270 to 300) and the short basic domain (from 342 to 351) located downstream from the bZIP. We also demonstrate that CREB-2 is acetylated by p300/CBP but not by p/CAF. Moreover, replacement of lysine by arginine in the basic domains decreases the trans-activating capacity of CREB-2. However, in the presence of Tax, the HTLV-I transcription remains fully activated by these CREB-2 mutants. Although we cannot totally exclude that the mutations could also affect CREB-2 structure and activity independent of acetylation, our results suggest that activation of the viral promoter in the presence of Tax is independent of the CREB-2 acetylation.

HTLV-I infection in the South West Indian Ocean islands, particularly in La Réunion and the Seychelles

Data on HTLV-I are scarce in several Southwest Indian Ocean islands except for La Réunion and The Seychelles. The two cases of HTLV-I have been confirmed by Western-Blot in La Réunion, among blood donors. In Seychelles (87 400 inhabitants in 2012), where blood donors and some other cases are screened, HTLV-I was confirmed with a line immune assay in 43 persons and at least 10-20 patients are known to have tropical spastic paraparesia or adult T-cell lymphoma associated with HTLV-I. In the south-west Indian Ocean, a possibly important other issue may be co-infection of HTLV-1 with the Strongyloides stercoralis roundworm, which is endemic in all countries of the region and which can sometimes lead to severe symptomatic infestation.