Pax5: the guardian of B cell identity and function

Nat Immunol. 2007 May;8(5):463-70. doi: 10.1038/ni1454.


The transcription factor Pax5 is essential for commitment of lymphoid progenitors to the B lymphocyte lineage. Pax5 fulfils a dual role by repressing B lineage 'inappropriate' genes and simultaneously activating B lineage-specific genes. This transcriptional reprogramming restricts the broad signaling capacity of uncommitted progenitors to the B cell pathway, regulates cell adhesion and migration, induces V(H)-DJ(H) recombination, facilitates (pre-)B cell receptor signaling and promotes development to the mature B cell stage. Conditional Pax5 inactivation in early and late B lymphocytes revealed an essential role for Pax5 in controlling the identity and function of B cells throughout B lymphopoiesis. PAX5 has also been implicated in human B cell malignancies, as it is deregulated by chromosomal translocations in a subset of acute lymphoblastic leukemias and non-Hodgkin lymphomas.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • B-Lymphocytes / metabolism*
  • B-Lymphocytes / pathology
  • Cell Differentiation / genetics*
  • Cell Lineage
  • Cell Transformation, Neoplastic / genetics
  • Gene Expression Regulation, Developmental / physiology*
  • Humans
  • PAX5 Transcription Factor / genetics
  • PAX5 Transcription Factor / physiology*


  • PAX5 Transcription Factor
  • PAX5 protein, human
  • Pax5 protein, mouse