title: Study on the Function of Tumor Necrosis Factor α Before and After Mutation in Hepatitis B.
abstract: OBJECTIVE
  To explore the cause of functional changes of TNF-α in removing hepatitis B virus (HBV) through the structural changes of each site in TNF-α before and after mutation.
  
  
  METHODS
  Three typical mutant sites (TNF-α-308G/A, 857C/T and 863C/A of TNF-α) were chosen and methods like ab initio modeling was adopted for 3D modeling of TNF-α before and after mutation. The structural changes were also analyzed. Then structural changes and functional changes were brought together for comparison to infer the root cause of the changes.
  
  
  RESULTS
  Mutation of TNF-α-308G/A led to the production of multiple helical structures and that of 863C/A caused the production of one helical structure in its adjacent region. Mutation of 857C/T, however, did not cause the change in the basic structure of TNF-α.
  
  
  CONCLUSIONS
  The helical structure of TNF-α may have a positive effect on the removal of hepatitis B virus.
authors.forename: Zhijun
authors.initials: Z
authors.lastname: Zhao
authors.forename: Jingtao
authors.initials: J
authors.lastname: Chen
authors.forename: Xiaoxiang
authors.initials: X
authors.lastname: Yin
authors.forename: Huayong
authors.initials: H
authors.lastname: Song
authors.forename: Xinchun
authors.initials: X
authors.lastname: Wang
mesh_terms: D006515:Hepatitis B virus / Q000378:metabolism*; D006801:Humans; D008958:Models, Molecular; D017433:Protein Structure, Secondary / Q000235:genetics*; D017434:Protein Structure, Tertiary / Q000235:genetics*; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics* / Q000378:metabolism
chemical_list: D014409:Tumor Necrosis Factor-alpha