Rabbit anti-Human IL4I1 Polyclonal Antibody

Uniprot Id

Q96RQ9

Target Species

Human

Target Name

IL4I1

Target Full Name

L-amino-acid oxidase

Target Function

Secreted L-amino-acid oxidase that acts as a key immunoregulator. Has preference for L-aromatic amino acids: converts phenylalanine (Phe), tyrosine (Tyr) and tryptophan (Trp) to phenylpyruvic acid (PP), hydroxyphenylpyruvic acid (HPP), and indole-3-pyruvic acid (I3P), respectively. Also has weak L-arginine oxidase activity. Acts as a negative regulator of anti-tumor immunity by mediating Trp degradation via an indole pyruvate pathway that activates the transcription factor AHR. IL4I1-mediated Trp catabolism generates I3P, giving rise to indole metabolites (indole-3-acetic acid (IAA) and indole-3-aldehyde (I3A)) and kynurenic acid, which act as ligands for AHR, a ligand-activated transcription factor that plays important roles in immunity and cancer. AHR activation by indoles following IL4I1-mediated Trp degradation enhances tumor progression by promoting cancer cell motility and suppressing adaptive immunity. Also has an immunoregulatory function in some immune cells, probably by mediating Trp degradation and promoting downstream AHR activation: inhibits T-cell activation and proliferation, promotes the differentiation of naive CD4(+) T-cells into FOXP3(+) regulatory T-cells (Treg) and regulates the development and function of B-cells. Also regulates M2 macrophage polarization by inhibiting T-cell activation. Also has antibacterial properties by inhibiting growth of Gram negative and Gram positive bacteria through the production of NH4(+) and H2O2.

Target Subcellular Location

Secreted. Lysosome. Cytoplasmic vesicle, secretory vesicle, acrosome.

Target Protein Families

Flavin monoamine oxidase family, FIG1 subfamily

Target Tissue Specificity

Primarily found in immune tissues, with the highest expression in lymph nodes and spleen. Present in germinal center macrophages and inflammatory myeloid cells and antigen-presenting cells (at protein level). Also present in spermatozoa (at protein level)

Target Research Area

Cell Biology

Target Synonyms

IL4I1; FIG1; UNQ636/PRO1265; L-amino-acid oxidase; LAAO; LAO; EC 1.4.3.2; Interleukin-4-induced protein 1; IL4-induced protein 1; Protein Fig-1; hFIG1

Target Background

This gene encodes a secreted L-amino acid oxidase protein which primarily catabolizes L-phenylalanine and, to a lesser extent, L-arginine. The expression of this gene is induced by the cytokine interleukin 4 in B cells. This gene is also expressed in macrophages and dendritic cells. This protein may play a role immune system escape as it is expressed in tumor-associated macrophages and suppresses T-cell responses. This protein also contains domains thought to be involved in the binding of flavin adenine dinucleotide (FAD) cofactor. Multiple transcript variants encoding different isoforms have been found for this gene. Some transcripts of this gene share a promoter and exons of the 5' UTR with the overlapping NUP62 gene.