Postnatal developmental of Neuromedin S and its receptor in the male Xiaomeishan pig reproductive axis

- We first study the pig NMS precursor and its receptors (NMUR1 and NMUR2) cDNA and analyzed their sequences.
- The study provides molecular, biological, and morphological evidence that the NMS/NMUR2 system exists in the male pig's HPT axis.
- NMS/NMUR2 system may play significant roles in reproduction at the level of the hypothalamus, pituitary and testis, similar to its function in other vertebrates.

Neuromedin S (NMS) has been identified as an endogenous ligand for FM-3/GPR66 and FM-4/TGR-1 which are NMU receptors NMUR1 and NMUR2, respectively. The NMS molecule is present in some peripheral tissues and the central nervous system (CNS), and it had been documented that NMS has fundamental and important roles in multiple physiological functions and processes such as circadian rhythm, energy balance, feeding behavior, stress responses and reproduction. The possible role of NMS in sexual development postnatally, however, is still obscure. This study aims to determine the change of NMS and its receptor gene expression in the reproductive axis of male Xiaomeishan pigs, postnatally. Firstly, the cDNA of the NMS and its receptors was cloned and sequenced. The results showed that there was a lack of 12 amino acids in the C-terminal of the male Xiaomeishan pig NMS amino-acid sequences compared with other animal species, but the main protein structure of prepro-NMS was high in homology. In addition, the nucleotide sequence and amino acids of the male Xiaomeishan pig's NMUR1 and NMUR2 had high homology. The NMS and NMUR2 mRNA in the male Xiaomeishan pig was detected in the reproductive axis at postnatal development stages, including postnatal day 3, 30, 60, 90 and 120, using real-time PCR and immunohistochemistry. The data showed that there were developmental changes in NMS and NMUR2 in the reproductive axis of the male Xiaomeishan pigs, postnatally, which suggested that NMS and NMUR2 might have a role in the development of the boar reproductive axis, but its regulatory mechanism remains to be elucidated.