jabbrv-ltwa-all.ldf jabbrv-ltwa-en.ldf Allogeneic inflammatory factor-1 (AIF-1) is a novel adipokine that plays a crucial role in fat metabolism. This study evaluated the effect and mechanism of AIF-1 on adipogenic differentiation of DF-1 fibroblast cell line in Tibetan chickens, aiming to provide insights for solving the problem of excessive abdominal fat accumulation in modern poultry. The results showed that the coding sequence (CDS) of the Tibetan chicken AIF-1 gene was 438 bp, and the predicted protein had a molecular weight of approximately 16.29 kDa, with a high arginine content that may promote adipocyte maturation. AIF-1 was highly expressed in the kidney and abdominal adipose tissue, and its expression increased during adipogenic differentiation of chicken pre-adipocytes, indicating its involvement in adipogenesis. Inhibition of AIF-1 expression resulted in a significant reduction in lipid droplet accumulation and intracellular triglyceride levels. In contrast, overexpression of AIF-1 enhanced lipid droplet formation and triglyceride content. In addition, inhibition of AIF-1 expression significantly down-regulated the expression of known key genes related to adipocyte differentiation: peroxisome proliferation-activated receptor γ (PPARγ) and perilipin 1 (PLIN1) in adipocytes. The expression levels of CCAAT enhancer binding protein β (C/EBP-β) and fatty acid binding protein 4 (FABP4) were also decreased. In adipocytes overexpressing AIF-1, the expression levels of PPARγ, C/EBP-β and FABP4 were significantly increased. Thus, adipogenic differentiation induced by AIF-1 might be related with PPARγ, PLIN1, C/EBP-β and FABP4 activation. In conclusion, Tibetan chicken AIF-1 is a positive regulatory factor in adipogenic differentiation, which promoted adipogenic differentiation and lipid accumulation of preadipocytes.