|Budget Amount *help
¥17,200,000 (Direct Cost : ¥17,200,000)
Fiscal Year 1997 : ¥1,200,000 (Direct Cost : ¥1,200,000)
Fiscal Year 1996 : ¥1,800,000 (Direct Cost : ¥1,800,000)
Fiscal Year 1995 : ¥14,200,000 (Direct Cost : ¥14,200,000)
Althoug the pathogenesis of Sjogren'S syndrome (SS) remains unclear, it has been reported that there is a high incidence of Epstein-Barr virus (EBV) reaction in SS.In this study, in order to clarify the association of EBV in SS pathogenesis and further analyze the mechansim of EBV reactivation, we assayd transcription of ZEBRA which is the fast transcribed EBV-encoded immediate early gene product and was an indispensable role in EBV reactivatio. ZEBRA mRNA was found in 2 SS B-cell lines, but not in rheumatoid arthritis (RA) B-cell line. These results suggest that EBV reactivation in SS was mediated by ZEBRA and occurred in salivary gland epithelial cells and peripheral B cells in SS patients.
On the other hand, to identify the inducer of EBV reactivation, we have udsed in vitro EBV reaction model (AKATA cells). Screening of AKATA cDNA by mRNA differential display, one clone, named 'AK-1', was highly expressed in EBV reactivating -cell lines (sIg-crosslinked AKATA,B95-8, P3HR-1), but not in latent-cell line (Raji). Nucleotide sequence analysis revealed that AK-1 was complete match with p300/CBP-associated factor (P/CSF). Furthermore, as another approach, we have partially cloned cDNA with a novel sequence containing a region homologous to the basic leucine zipper domain of CREB/ATF family by degenerate PCR.
At this time, the role of P/CAF in EBV reactivation is unknown. However, recent published studies have implicated that an CREB family transcription factor involved in ZEBRA transcription. Upon this CREB-medicate transcription, p300, which express ubiquitously, work as a positive transcriptional co-factor. Therefore, our results together with recent reports, suggest the possibility that CREB family protein-p300-P/CAF ternary complex on ZEBRA promoter might be involved in ZEBRA transcriptional activation.