Characterization of the fatty acid binding protein 3 (FABP3) promoter and its transcriptional regulation by cAMP response element binding protein 1 (CREB1) in goat mammary epithelial cells

Abstract

Fatty acid binding protein 3 (FABP3) is involved in signal transduction pathways, and in the uptake and utilization of long-chain fatty acids. However, the transcriptional regulation of FABP3 in goat is unclear. In this study, the FABP3 5′ flanking region was amplified from goat (Capra hircus) genomic DNA. Luciferase reporter vectors containing promoter fragments of five different lengths were constructed and transfected into dairy goat mammary epithelial cells. The region of the promoter located between −1801 and −166 bp upstream of the transcription start site (TSS) exhibited the highest luciferase activity, and contained two cAMP response elements (CREs) located at −1632 bp and −189 bp. Interference with CREB1 significantly downregulated FABP3 promoter activity. In addition, FABP3 promoter activity was significantly reduced after mutation of the CRE1 (−1632 bp) and CRE2 (−189 bp) sites. Further analysis indicated that the CRE2 site was essential for the transcriptional activity induced by CREB1. These results demonstrated that CREB1 is involved in the transcriptional regulation of FABP3 expression in the goat mammary gland via a direct mechanism, thus revealing a novel signaling pathway involved in fatty acid metabolism in goat.

Keywords:

• Fatty acid binding protein 3 (FABP3) promoter
• CREB1
• transcriptional regulation
• dairy goat

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research was jointly supported by the Innovative Research and Experimental Projects for Young Researchers of Tianjin Academy of Agricultural Sciences (2021010), the National Natural Science Foundation of China (No.31702095), Natural Science Foundation of Tianjin (No.18JCYBJC30200), Tianjin Science and Technology planning project (No.21ZYCGSN00190), Tianjin Science and Technology planning project (No.19ZXZYSN00010), and Tianjin ‘131’ Innovative Talents Team (20180338).