EndoU is a novel regulator of AICD during peripheral B cell selection

Poe, Jonathan C.; Kountikov, Evgueni I.; Lykken, Jacquelyn M.; Natarajan, Abirami; Marchuk, Douglas A.; Tedder, Thomas F.

The current studies demonstrate for the first time that an RNA-binding protein plays a major role in regulating AICD, c-Myc expression, and the phenotype of peripheral B cells. Furthermore, these studies suggest an EndoU, CD22, c-Myc, and CD19 regulatory loop that directs normal B cell survival and malignant transformation (Fujimoto et al., 1999; Poe et al., 2012) . EndoU likely regulates c-Myc and potentially other crucial ssRNA (mRNA or pre-mRNA) transcripts and nonclassical ssRNAs that directly regulate or fine-tune specific subsets of genes required for optimal B cell proliferation and survival. For autoreactive B cells that survive central selection and inhabit peripheral tissues, EndoU overexpression has nonetheless evolved as a checkpoint protein within the complex pathway that keeps potentially pathogenic B cells at bay through deletion via AICD.