Toll-like receptor 4 (Chicken) (TLR4)

Toll-like receptor 4 (TLR4) in chickens (Gallus gallus) is a vital transmembrane protein that serves as a pattern recognition receptor (PRR) within the innate immune system [UniProt: O77474]. It is primarily responsible for detecting lipopolysaccharide (LPS), a major component of the outer membrane of Gram-negative bacteria [PMID: 22461490]. Upon activation, chicken TLR4 triggers a signaling cascade involving the adapter protein MyD88, which leads to the activation of transcription factors like NF-kappaB and the subsequent release of pro-inflammatory cytokines such as IL-1beta and IL-6 [PMID: 15661922]. This receptor is a significant focus in poultry science because genetic variations in the TLR4 gene are linked to susceptibility or resistance to common avian pathogens, including Salmonella and Escherichia coli [NCBI Gene: 396248]. While it shares functional similarities with mammalian TLR4, the chicken ortholog exhibits distinct structural requirements, such as a specific interaction with chicken MD-2 for ligand recognition [PMID: 22461490]. Therapeutic strategies targeting chicken TLR4 include the use of TLR4 agonists as vaccine adjuvants to bolster immune memory and the development of antagonists to prevent sepsis-related inflammatory damage.

Other names

chTLR4Toll-like receptor 4Gallus gallus TLR4

Chicken TLR4 acts by forming a complex with MD-2 and CD14 to bind bacterial lipopolysaccharide, which induces receptor dimerization and recruitment of intracellular adapter proteins like MyD88, ultimately triggering the NF-kappaB signaling pathway to initiate an inflammatory immune response [PMID: 22461490].