Disease relevance of U94

• The amino acid sequences of 13 of the 17 ORFs at the right end of U differ by more than 10%, with the notable exception of U94, the adeno-associated virus type 2 rep homolog, which differs by only 2.4% [1].
• We report that peripheral blood mononuclear cells of healthy individuals infected with HHV-6 express the U94 gene, transcribed under IE conditions [2].
• Three gene transcripts (U31, U39, and U94) were detected in 90-100% of the PBMC samples collected from febrile period of exanthem subitum patients, from which HHV-6 was isolated [3].

High impact information on U94

• These findings are consistent with the hypothesis that the U94 gene product of HHV-6 regulates viral gene expression and enables the establishment and/or maintenance of latent infection in lymphoid cells [2].
• To verify that U94 may play a role in the maintenance of the latent state, we derived lymphoid cell lines that stably expressed U94 [2].
• The detection of antibodies specific for HHV-6 U94/REP shows that the immune system is exposed to this antigen during natural infection [4].
• U94 nucleotide and amino acid sequences differ by approximately 3.5% and 2.5%, respectively, between HHV-6A and HHV-6B [5].
• Neither the U31 gene nor the U94 gene transcript was detected in any of the 10 samples [3].

Anatomical context of U94

• U94 of human herpesvirus 6 is expressed in latently infected peripheral blood mononuclear cells and blocks viral gene expression in transformed lymphocytes in culture [2].

Analytical, diagnostic and therapeutic context of U94

• The higher prevalence and higher titers of antibodies to U94/REP suggest that MS patients and control groups might experience different exposures to HHV-6 [4].
• Quantitative RT-PCR and PCR with primers specific for MSRV/HERV-W env and pol and HHV-6 U94/rep and DNA-pol were used to determine virus copy numbers [6].

References