title: Cell death gene expression profile: role of RIPK2 in dengue virus-mediated apoptosis.
abstract: Dengue virus (DENV) is a major emerging arthropod-borne pathogen, which infects individuals in both subtropical and tropical regions. Patients with DENV infection exhibit evidence of hepatocyte injury. However, the mechanisms of hepatocyte injury are unclear. Therefore we examined the expression of cell death genes during DENV-infection of HepG2 cells using real-time PCR arrays. The expression changes were consistent with activation of apoptosis and autophagy. Expression of the up-regulated genes, including RIPK2, HRK, TGF-β, PERK, and LC3B, was confirmed by quantitative real-time PCR. RIPK2 belongs to the receptor-interacting protein family of serine/threonine protein kinases, which is a crucial mediator of multiple stress responses that leads to the activation of caspase, NF-κB and MAP kinases including JNK and p38. RIPK2 activity is inhibited by the p38 MAPK pathway inhibitor SB203580. The effect of SB203580 on RIPK2 expression and DENV-induced apoptosis was tested in DENV-infected HepG2 cells. The inhibition of RIPK2 expression by SB203580 significantly reduced apoptosis. SB203580 also significantly reduced DENV capsid protein (DENVC)-mediated apoptosis. Suppression of endogenous RIPK2 in DENV-infected HepG2 cells by small interfering RNA (siRNA) significantly decreased apoptosis suggesting for the first time that RIPK2 plays a role in DENV-mediated apoptosis.
authors.affiliation: Medical Molecular Biology Unit, Office for Research and Development, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: Atthapan
authors.initials: A
authors.lastname: Morchang
authors.forename: Umpa
authors.initials: U
authors.lastname: Yasamut
authors.forename: Janjuree
authors.initials: J
authors.lastname: Netsawang
authors.forename: Sansanee
authors.initials: S
authors.lastname: Noisakran
authors.forename: Wiyada
authors.initials: W
authors.lastname: Wongwiwat
authors.forename: Pucharee
authors.initials: P
authors.lastname: Songprakhon
authors.forename: Chatchawan
authors.initials: C
authors.lastname: Srisawat
authors.forename: Chunya
authors.initials: C
authors.lastname: Puttikhunt
authors.forename: Watchara
authors.initials: W
authors.lastname: Kasinrerk
authors.forename: Prida
authors.initials: P
authors.lastname: Malasit
authors.forename: Pa-thai
authors.initials: PT
authors.lastname: Yenchitsomanus
authors.forename: Thawornchai
authors.initials: T
authors.lastname: Limjindaporn
mesh_terms: D017209:Apoptosis; D045744:Cell Line, Tumor; D003716:Dengue Virus / Q000378:metabolism*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D056945:Hep G2 Cells; D006801:Humans; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D053475:Receptor-Interacting Protein Serine-Threonine Kinase 2 / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D034741:RNA, Small Interfering; D053475:Receptor-Interacting Protein Serine-Threonine Kinase 2