Expression and functional analyses of Krüppel-like factor 3 in chicken adipose tissue.

Studies in mammalian species showed that Krüppel-like factor 3 (KLF3) regulated adipose tissue development. However, it was not reported in chicken. In the current study, we found that during the growth and development of abdominal fat tissue, chicken KLF3 (Gallus gallus KLF3, gKLF3) was consecutively expressed, and its transcripts were higher at 7 weeks of age and lower at 10 weeks of age in lean broilers than in fat broilers. In addition, gKLF3 overexpression suppressed chicken CCAAT/enhancer binding protein alpha (C/EBPα), fatty acid binding protein 4 (FABP4), fatty acid synthase (FASN), and lipoprotein lipase (LPL) promoter activities, but increased chicken peroxisome proliferator-activated receptor gamma (PPARγ) promoter activity. Additionally, point mutagenesis analysis showed that the substitution of Asp by Gly within the Pro-Val-Asp-Leu-Thr (PVDLT) motif of gKLF3 significantly reduced the ability of gKLF3 to regulate the promoter activities of FABP4, FASN, LPL, C/EBPα, and PPARγ.