Intracellular Localization and Cellular Factors Interaction of HTLV-1 and HTLV-2 Tax Proteins: Similarities and Functional Differences

• Main Authors: Maria Grazia Romanelli, Carlo Bidoia, Gianfranco Di Gennaro, Francesca Avesani, Marco Turci, Umberto Bertazzoni
• Format: Article
• Language: English
• Published: MDPI AG 2011-05-01
• Series: Viruses
• Subjects: HTLV; Tax-1; Tax-2; signal transduction; cellular localization; post-translational modifications; NF-kB; PDZ binding motif
• Online Access: http://www.mdpi.com/1999-4915/3/5/541/

Human T-lymphotropic viruses type 1 (HTLV-1) and type 2 (HTLV-2) present very similar genomic structures but HTLV-1 is more pathogenic than HTLV-2. Is this difference due to their transactivating Tax proteins, Tax-1 and Tax-2, which are responsible for viral and cellular gene activation? Do Tax-1 and Tax-2 differ in their cellular localization and in their interaction pattern with cellular factors? In this review, we summarize Tax-1 and Tax-2 structural and phenotypic properties, their interaction with factors involved in signal transduction and their localization-related behavior within the cell. Special attention will be given to the distinctions between Tax-1 and Tax-2 that likely play an important role in their transactivation activity.