DEFB4B

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Description

The DEFB4B (defensin beta 4B) is a protein-coding gene located on chromosome 8.

DEFB4B exhibits antimicrobial activity against both Gram-negative and Gram-positive bacteria, showing stronger effects against Gram-negative bacteria. Its activity against Pseudomonas aeruginosa is sensitive to salt concentrations, being reduced at levels exceeding 25 mM. DEFB4B also demonstrates antimicrobial activity against the yeast Candida albicans. It permeabilizes Candida albicans cell membranes by targeting phosphatidylinositol 4,5-bisphosphate (PIP2) in the plasma membrane, leading to cell fragmentation and death. DEFB4B acts as a ligand for the C-C chemokine receptor CCR6, binding to it and inducing chemotaxis in CCR6-expressing cells such as immature dendritic cells and memory T cells.

DEFB4B is also known as DEFB4P.

Associated Diseases

• immunodeficiency 28
• varicella, severe recurrent
• recurrent Neisseria infections due to factor D deficiency
• candidiasis, familial, 4
• X-linked severe congenital neutropenia
• type II complement component 8 deficiency
• autosomal recessive severe congenital neutropenia due to JAGN1 deficiency
• immunodeficiency 53
• mannose-binding lectin deficiency
• autosomal recessive severe congenital neutropenia due to CSF3R deficiency
• combined immunodeficiency due to moesin deficiency
• immunodeficiency due to ficolin3 deficiency
• agammaglobulinemia 7, autosomal recessive
• neutropenia, severe congenital, 1, autosomal dominant
• TFRC-related combined immunodeficiency