1. Interleukin-6 (IL-6) is a multifunctional cytokine involved in lipid metabolism in adipose tissue. The objective of the study was to identify and characterize the IL-6 gene in the goose. 2. A full-length coding sequence (CDS) of the goose (Anser anser) IL-6 gene was cloned that encoded a 234-amino acid peptide containing a 38-amino acid signal peptide, an IL-6/G-CSF/MGF family consensus pattern and four conserved α-helices. The mature goose IL-6 showed 74% and 39% identities to that of chicken and human, respectively. 3. Quantitative real-time PCR analysis showed that the goose IL-6 was predominantly expressed in liver and was up-regulated in adipocytes by lipopolysaccharide (LPS) and oleic acid.

1. Toll-like receptors (TLRs) are type I transmembrane proteins that play an essential role in the innate immune system. Studies on the structure and function of TLRs can be applied to the development of new approaches to control diseases of humans and animals. 2. A 3432-bp cDNA encoding duck toll-like receptor 4 (duTLR4) was cloned from duck splenic lymphocytes using RT-PCR and rapid amplification of cDNA ends. 3. The encoded protein, which was predicted to contain 843 amino acids, had a molecular weight of 96·01 kDa and included an archetypal toll/interleukin-1 receptor domain, a transmembrane domain, and a distinctive arrangement of extracellular leucine-rich repeat regions similar to chicken TLR4, human TLR4, and mouse TLR4. The duTLR4 showed 82·1% amino acid sequence identity with previously described chicken TLR4, and 43·2–45·2% sequence identity with mammalian homologs. 4. RT-qPCR analysis indicated that the duTLR4 gene was strongly expressed in the liver, kidney, spleen, intestine, and brain.