Bruton's tyrosine kinase is required for activation of IκB kinase and nuclear factor κB in response to B cell receptor engagement

James B. Petro, S. M.Jamshedur Rahman, Dean W. Ballard, Wasif N. Khan

Research output: Contribution to journalArticle

237 Scopus citations


Mutations in the gene encoding Bruton's tyrosine kinase (btk) cause the B cell deficiency diseases X-linked agammaglobulinemia (XLA) in humans and X- linked immunodeficiency (xid) in mice. In vivo and in vitro studies indicate that the BTK protein is essential for B cell survival, cell cycle progression, and proliferation in response to B cell antigen receptor (BCR) stimulation. BCR stimulation leads to the activation of transcription factor nuclear factor (NF)-κB, which in turn regulates genes controlling B cell growth. We now demonstrate that a null mutation in btk known to cause the xid phenotype prevents BCR-induced activation of NF-κB. This defect can be rescued by reconstitution with wild-type BTK. This mutation also interferes with BCR-directed activation of IκB kinase (IKK), which normally targets the NF-κB inhibitor IκBα for degradation. Taken together, these findings indicate that BTK couples IKK and NF-κB to the BCR. Interference with this coupling mechanism may contribute to the B cell deficiencies observed in XLA and xid.

Original languageEnglish (US)
Pages (from-to)1745-1753
Number of pages9
JournalJournal of Experimental Medicine
Issue number10
StatePublished - May 15 2000
Externally publishedYes



  • Antigen receptor signaling
  • Tec family tyrosine kinase
  • Transcription factor
  • X-linked agammaglobulinemia
  • X-linked immunodeficiency

ASJC Scopus subject areas

  • Immunology

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