title: Dimerization of hepatitis B viral X protein synthesized in a cell-free system.
abstract: Hepatitis B viral X protein (HBx), a 17-kDa polypeptide, has been demonstrated as a trans-acting factor. In this study, we report that the HBx was able to form a dimer, a feature very similar to many well known trans-acting factors. In vitro synthesized HBx, after immunoprecipitation and analysis by SDS-PAGE, appeared as one prominent 17-kDa band (monomer) and a faint 34-kDa band (dimer). The amount of dimer increased if the sample of immunoprecipitated HBx was not treated with 2-mecaptoethanol, indicating the dimer was held together by the disulfide linkage. Dimerization of a truncated HBx established that the four cysteine residues close to the N-terminus are sufficient for the dimerization process.
authors: Graduate Institute of Microbiology and Immunology, National Yang-Ming Medical College, Taipei, Taiwan, Republic of China.
authors: M H
authors: MH
authors: Lin
authors: S C
authors: SC
authors: Lo
mesh_terms: D002474:Cell-Free System; D015180:Electrophoresis, Gel, Two-Dimensional; D006515:Hepatitis B virus / Q000378:metabolism*; D011108:Polymers; D011233:Precipitin Tests; D014176:Protein Biosynthesis; D015183:Restriction Mapping; D015534:Trans-Activators / Q000096:biosynthesis* / Q000235:genetics; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D011108:Polymers; D015534:Trans-Activators; D014764:Viral Proteins