Biopolym. Cell. 2013; 29(6):454-462.
Structure and Function of Biopolymers
Phylogenetic study on structural elements of HIV-1 poly(A) region. 1. PolyA and DSE hairpins
1Zarudnaya M. I., 1Potyahaylo A. L., 1Kolomiets I. M., 1Hovorun D. M.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680

Abstract

Genome of human immunodeficiency virus type 1 (HIV-1) is highly heterogeneous. The aim of this work was a phylogenetic study on structural elements of the HIV-1 poly(A) region, in particular polyA and DSE hairpins which compose a core poly(A) site. Methods. The secondary structure of the HIV-1 core poly(A) site has been predicted by the UNAFold program. Results. The structure of the polyA and DSE hairpins has been analysed in 1679 HIV-1 genomes of group M and 18 genomes of simian immunodeficiency virus SIVcpzPtt. We found 244 and 171 different sequences for the HIV-1 polyA and DSE hairpins, respectively. However 70 % of the HIV-1 isolates studied contain one of 7 variants of the polyA hairpin which occur with a frequency 5 % (main variants) and 79 % of the isolates contain one of 7 main variants of the DSE hairpin. We also revealed subtype and country specific mutations in these hairpins. We found that the SIV polyA hairpin most closely resembles that found in HIV-1 genomes of B/C subtypes. Conclusions. The results of our large-scale phylogenetic study support some structural models of the HIV-1 5' UTR, in particular the tertiary interaction between the polyA hairpin and the matrix region in HIV-1 gRNA. Possibly, the DSE hairpin appeared in the course of viral evolution of the HIV-1 group M. An exposure of the U/GU-rich element in the apical loop of DSE hairpin could significantly increase the efficiency of pre-mRNA polyadenylation in this HIV-1 group.
Keywords: HIV-1, SIVcpzPtt, poly(A) region, secondary structure, polyA hairpin, DSE hairpin

Supplementary data

References

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