CARD11

CARD11, also known as Caspase Recruitment Domain Family Member 11, is a protein that in humans is encoded by the CARD11 gene. This gene plays a crucial role in lymphocyte activation and the adaptive immune system. CARD11 is a member of the CARD domain-containing membrane-associated guanylate kinase (MAGUK) family, which is involved in coordinating responses to various intracellular signals.

Function

CARD11 functions as a crucial mediator in the nuclear factor kappa B (NF-κB) signaling pathway, which is essential for lymphocyte activation, proliferation, and survival. Upon engagement of the T-cell receptor (TCR) or B-cell receptor (BCR), CARD11 interacts with BCL10 and MALT1 to form a complex, leading to the activation of NF-κB. This signaling cascade plays a vital role in the immune response to pathogens and in maintaining immune system homeostasis.

Clinical Significance

Mutations in the CARD11 gene have been associated with various immunodeficiency disorders, including severe combined immunodeficiency (SCID) and B-cell expansion with NF-κB and T-cell anergy (BENTA) disease. These conditions are characterized by impaired immune responses and increased susceptibility to infections. Additionally, aberrant CARD11 signaling has been implicated in the development of certain types of cancer, such as diffuse large B-cell lymphoma (DLBCL), underscoring its importance in both immune regulation and oncogenesis.

Structure

The CARD11 protein contains several key domains, including a CARD domain, a coiled-coil domain, and a MAGUK domain. These domains facilitate its role as a scaffold protein, mediating interactions between various signaling molecules in the NF-κB pathway.

Research

Ongoing research aims to further elucidate the mechanisms by which CARD11 regulates immune responses and to explore potential therapeutic targets within the CARD11 signaling pathway for the treatment of immunodeficiency disorders and cancers.