Methods for Identifying and Examining HTLV-1 HBZ Post-translational Modifications.

Post-translational modifications (PTMs) are chemical alterations to individual amino acids that alter a protein's conformation, stability, and/or function. Several pathogenic viruses have been shown to encode proteins with PTMs, including human T-cell leukemia virus type 1 (HTLV-1) Tax and Rex regulatory proteins. HTLV-1 basic leucine zipper protein (HBZ) was hypothesized to feature PTMs due to its functional activities and interactions with cellular transcription factors and acetyltransferases. Here, we describe the approach used to identify, via mass spectrometry, the PTMs of HBZ. In addition, we describe methods to determine the functional relevance of the identified PTMs.