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bioRxiv · 10.1101/295915

An inter-chromosomal transcription hub activates the unfolded protein response in plasma cells

Bortnick, A.·He, Z.·Aubrey, M.·Chandra, V.·Denholtz, M.·Chen, K.·Lin, Y. C.·Murre, C.
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Abstract

Previous studies have indicated that the transcription signature of antibody-secreting cells is closely associated with the induction of the unfolded protein response pathway (UPR). Here we have used genome-wide and single cell analyses to examine the folding patterns of plasma cell genomes. We found that plasma cells adopt a cartwheel configuration and undergo large-scale changes in chromatin folding at genomic regions associated with a plasma cell specific transcription signature. During plasma cell differentiation, Blimp1 assembles into an inter-chromosomal transcription hub with genes associated with the UPR, biosynthesis of the endoplasmic reticulum (ER) as well as a cluster of genes linked with Alzheimers disease. We suggest that the assembly of the Blimp1-UPR-ER transcription hub permits the coordinate activation of a wide spectrum of genes that collectively establish plasma cell identity.

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Bortnick, A., He, Z., Aubrey, M., Chandra, V., Denholtz, M., Chen, K., Lin, Y. C., Murre, C.. 2018-04-06. An inter-chromosomal transcription hub activates the unfolded protein response in plasma cells. https://doi.org/10.1101/295915

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