Recent findings suggest that the gastrointestinal tract (GIT) can sense varies kinds of nutrients via G-protein coupled receptors (GPCRs) expressed throughout the gut epithelium in both human and rodents. Dietary fat can also be sensed by GPCRs in the form of free fatty acids (FFAs). It is now apparent that GPR120 responds to long-chain FFAs. However, when compared with rodent and human models, much less is known about GPR120 in ruminants. Here comes the question: can fat be "tasted" in the gastrointestinal tract of Goats as nonruminants do?

In a recent study, PhD. ZHOU Chuanshe and his group from Institute of Subtropical Agriculture, Chinese Academy of Sciences (ISA), led by professor TAN Zhiliang, have reported that the GIT of Goats have the potential to "taste" dietary fat. Firstly, partial coding sequence (CDS) of g-GPR120 has been cloned from goats, and phylogenetic analysis revealed that g-GPR120 shared higher homology in both mRNA and amino acid sequences for ruminants than non-ruminants. Immunochemistry, real-time PCR and Western blot analysis have revealed that g-GPR120 is expressed throughout the digestive tracts of goats, with higher expression level in the hindgut (especially the colon). Moreover, the effect of feeding system on the expression of g-GPR120 is furtherly studied, and proven that supplemental feeding can increase the expression of g-GPR120.

This team studied the GPR120 in ruminants for the first time, and proved that g-GPR120 mediated LCFA chemosensing mechanism is widely present in the GIT of goats. The study of g-GPR120 provides opportunity to understand ways of improving dietary energetic efficiency in ruminants, providing greater flexibility in feeding management.

This research had received financial support from the National Natural Science Foundation of China (Grant No. 31320103917), "Strategic Priority Research Program - Climate Change: Carbon Budget and Relevant Issues"(Grant No.XDA05020700), "CAS Visiting Professorship for Senior International Scientists (Grant No. 2010T2S13, 2012T1S0009), and Hunan Provincial Creation Development Project (Grant No. 2013TF3006).

The article has been published on Journal of Agricultural and Food Chemistry, details could be found at http://pubs.acs.org/doi/abs/10.1021%2Facs.jafc.5b06131 

Contact: ZHOU Chuanshe

E-mail: zcs@isa.ac.cn

Institute of Subtropical Agriculture, Chinese Academy of Sciences