Blimp1: a conserved transcriptional repressor critical for differentiation of many tissues.

B lymphocyte induced maturation protein 1 (Blimp1) is a zinc finger transcriptional repressor whose function as a master regulator of terminal differentiation of B cells into plasma cells has long been studied and is well established. Recent studies have identified novel roles for Blimp1 including homeostasis of effector T cells, specification of primordial germ cells in mouse, specification of muscle fiber type in zebrafish and as a tumor suppressor gene in germinal center derived B cells. Blimp1 associates with a multitude of chromatin modifying enzymes inducing epigenetic changes at specific targets to regulate these diverse cell fates. In this review, we focus on the novel and emerging roles of Blimp1 in multiple tissues, on mechanisms of transcriptional repression by Blimp1 and on the activity of Blimp1 as a tumor suppressor.