Transcriptome analysis of WEHI B lymphoma cells overexpressing individual NFATc1 proteins

In lymphocytes, NFATc1 is the most prominent NFAT transcription factor which play a crucial role in the fate and activity of peripheral T and B cells. NFATc1 is synthesized in two prominent isoforms, the inducible short isoform NFATc1/aA and the constitutively expressed long isoform NFATc1/ßC. Several lines of evidence suggested that both isoforms differ markedly in their function. It was speculated that NFATc1/aA supports the proliferation and survival of lymphocytes, whereas NFATc1/ßC should support apoptosis and anergy induction. To proof this hypothesis we established WEHI 231 B lymphoma cells that stably (over-) express either NFATc1/aA or NFATc1/ßC. In preliminary experiments we could should that WEHI cells overexpressing NFATc1/aA were protected against apoptosis induction, while cells overexpressing NFATc1/ßC should a higher apoptosis rate. Transcriptom analysis of WEHI-231 cells overexpressing either NFATc1/aA or NFATc1/ßC were performed, along with a control group of WEHI-231 cells overexpressing the E.coli enzyme BirA Ligase (which is also present in all target cell lines since – for further molecular assays – the NFATc1 proteins were expressed as chimeric protein containing C-terminal bio-tags. The experimental results obtained indicate that the both NFATc1 proteins, NFATc1/aA and NFATc1/ßC, differ tremendously in their transcriptional properties.