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bioRxiv · 10.1101/2022.09.21.508949

Transcription factor TFII-I fine tunes innate properties of B lymphocytes

Singh, A.·Kaileh, M.·De, S.·Mazan-Mamczarz, K.·Bayarsaihan, D.·Sen, R.·Roy, A.
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Abstract

The ubiquitously expressed transcription factor TFII-I is a multifunctional protein with pleiotropic roles in gene regulation. TFII-I associated polymorphisms are implicated in Sjogrens syndrome and Lupus in humans and, germline deletion of the Gtf2i gene in mice leads to embryonic lethality. Here we report a unique role for TFII-I in homeostasis of innate properties of B lymphocytes. Loss of Gtf2i in murine B lineage cells leads to a change in transcriptome and chromatin landscape, which resembles myeloid-like features and coincides with enhanced sensitivity to LPS induced transcription. TFII-I deficient B cells also show increased switching to IgG3, a phenotype associated with inflammation. These results demonstrate a role for TFII-I in maintaining immune homeostasis and provide clues for GTF2I polymorphisms associated with B cell dominated autoimmune diseases in humans.

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Singh, A., Kaileh, M., De, S., Mazan-Mamczarz, K., Bayarsaihan, D., Sen, R., Roy, A.. 2022-09-22. Transcription factor TFII-I fine tunes innate properties of B lymphocytes. https://doi.org/10.1101/2022.09.21.508949

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