title: CDC42-Interacting Protein 4 Gene Is Down Trans-Regulated by HBV DNA polymerase Trans Activated Protein 1.
abstract: BACKGROUND
  Hepatitis B Virus (HBV) DNA polymerase transactivated protein 1 (HBVDNAPTP1) is a novel protein transactivated by HBV DNA polymerase, screened by suppression subtractive hybridization technique (GenBank accession no: AY450389). The biological function of HBVDNAPTP1 was investigated in this study.
  
  
  METHODS
  We constructed a vector pcDNA3.1 (-)/myc-His A-HBVDNAPTP1 and used it to transfect acute monocytic leukemia cell line THP-1. HBVDNAPTP1 expression was detected by western blot analysis in the cells. A cDNA library of genes transactivated by HBVDNAPTP1 in THP-1 cells was made in pGEM-T Easy using suppression subtractive hybridization (SSH). The cDNAs were sequenced and analyzed with BLAST search against the sequences in GenBank.
  
  
  RESULTS
  Some sequences, such as CIP4, might be involved in apoptosis development. mRNA and protein expression of CIP4 was identified by Real time RT-PCR and western blot in THP-1 cells. HBVDNAPTP1 could down-regulate the expression of CIP4 at both transcription and translation levels.
  
  
  CONCLUSIONS
  HBVDNAPTP1 may be involved in the positive regulation on the initiation of monocyte apoptosis. The result contribute to reveal the HBVDNAPTP1 biological functions and provide new evidences for further exploration of the regulatory mechanism of HBVDNAPTP1.
authors.affiliation: 1. Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University Dalian, China.
authors.forename: Yongzhi
authors.initials: Y
authors.lastname: Lun
authors.affiliation: 1. Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University Dalian, China.
authors.forename: Chongbo
authors.initials: C
authors.lastname: Xu
authors.affiliation: 1. Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University Dalian, China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Chi
authors.affiliation: 1. Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University Dalian, China.
authors.forename: Xuelei
authors.initials: X
authors.lastname: Wang
authors.affiliation: 1. Liaoning Provincial University Key Laboratory of Biophysics, College of Medicine, Dalian University Dalian, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Sui
authors.affiliation: 2. Department of Gynecology and Obstetrics, Affiliated Zhongshan Hospital of Dalian University , Dalian, China.
authors.forename: Sujuan
authors.initials: S
authors.lastname: Jiang
keywords: CDC42-interacting protein 4; DNA polymerase; Hepatitis b virus; Suppression subtractive hybridization; Trans-regulation