Features of TAT, REV, and VPU proteins of HIV-1 Sub-subtype A6 in patients with an established diagnosis of AIDS

The aim . To study the characteristics of the viral proteins Tat, Rev and Vpu in patients infected with HIV-1 sub-subtype A6 variants with a confirmed diagnosis of AIDS. Materials and methods . The comparative analysis of the genetic diversity in proteins was conducted in two groups of patients: with an established diagnosis of AIDS (25 people) and without an established diagnosis of AIDS (62). Whole blood samples from patients observed at the AIDS Prevention and Control Center of the Republic of Crimea were analyzed. Proviral DNA was isolated, the corresponding genomic regions were amplified, genotyping was performed, nucleotide sequences were converted to amino acid sequences, and amino acid substitutions with significantly different frequencies were identified between the two groups. Results and discussion . All patients included in the study were infected with HIV-1 subtype A6. The following substitutions were significantly more common in patients diagnosed with AIDS: T77A and T97P — in Tat, V16A, Q74H and R50N — in Rev, V10I and L33I — in Vpu. Most of these substitutions are located at positions overlapping linear epitopes, which may indicate selective pressure from the immune system at these positions. Conclusion . V16A in Rev and V10I in Vpu are marked for further study, as they are located at amino acid residue positions potentially involved in interactions with the inhibitors of the functional activity of these proteins.