Characterisation of NF-κB complexes in Theileria parva-transformed T cells

• Published in: Microbes and infection Vol. 2; no. 11; pp. 1311 - 1320
• Main Authors: Machado, Joel, Fernandez, Paula C, Baumann, Ina, Dobbelaere, Dirk A.E
• Format: Journal Article
• Language: English
• Published: Elsevier SAS 01.09.2000
• Subjects: NF-^KB protein; parasite; signalling pathway; Theileria parva; transcription factor; signalling pathway; transcription factor; parasite
• ISSN: 1286-4579; 1769-714X
• DOI: 10.1016/S1286-4579(00)01284-3

Transformation of T cells by the intracellular parasite Theileria parva is accompanied by constitutive I-κB degradation and NF-κB activation, a process which is essential to prevent the spontaneous apoptosis of these parasite-transformed cells. NF-κB-mediated responses are regulated by selective combinations of NF-κB proteins as homo- or heterodimers and by distinct κB motifs. We characterised the NF-κB complexes induced by T. parva infection in TpM(803) T cells. By western blot, we demonstrated that all members of the NF-κB/Rel family of proteins translocate to the nucleus of infected cells. Using two different κB oligonucleotides (κB-1 and κB-2), both containing the decameric consensus κB motif (GGGACTTTCC), clearly distinct patterns of DNA binding activities could be demonstrated in electrophoretic mobility shift assays. Supershift analysis and UV cross-linking assays showed that complexes binding to κB-1 consisted of p50, p65 and RelB homo and/or heterodimers. We could also detect an association of ATF-2 and c-Fos with one of the complexes. The HIV-derived κB-2 oligo only bound p50 and p65. Additionally, several agents known to inhibit a wide range of NF-κB activation pathways had no inhibitory effect on the activation of NF-κB DNA binding in TpM(803) T cells.