CARD11

CARD11, also known as Caspase Recruitment Domain Family, Member 11, is a protein encoded by the CARD11 gene in humans. It is a key component of the B cell receptor (BCR) signaling pathway, which is essential for the development and function of B lymphocytes, a type of white blood cell that produces antibodies.

The CARD11 protein plays a crucial role in activating transcription factor NF-κB, a complex that regulates genes involved in immune responses, cell survival, and proliferation. It acts as a scaffold protein, bringing together various signaling molecules within the cell to facilitate the activation of downstream pathways. Upon activation of the BCR, CARD11 undergoes conformational changes that enable its interaction with other proteins, ultimately leading to the activation of the NF-κB pathway.

Mutations in the CARD11 gene can lead to severe immunodeficiency disorders. These mutations can disrupt the normal function of CARD11, impairing B cell development and antibody production. Consequently, individuals with CARD11 mutations are highly susceptible to recurrent infections. These disorders are often referred to as B cell expansion with neutropenia (BENG) or other related conditions, depending on the specific genetic defect and its phenotypic consequences. Research into CARD11 and its associated pathways continues to advance our understanding of immune system regulation and the molecular basis of certain immunodeficiencies.