Cloning and expression of neuron-specific enolase in the corpus luteum of dairy goats

Neuron-specific enolase (NSE) is the key molecular marker for diffuse neuroendocrine system (DNES) cells, its expression in the pregnant corpus luteum (CL) of dairy goats was studied by the immunofluorescence method and the ultra structural characteristics of luteal cells were detected by the electron microscopy to identify the existence of DNES cells in the pregnant CL of dairy goats. Besides, the coding sequence of dairy goats NSE gene was cloned and its biological information was analyzed. Results revealed that NSE immunopositive cells exhibited widespread cytoplasmic staining throughout the whole pregnant CL. In addition, these cells showed typical characteristics of DNES cells in the electron microscopy. These results suggested that many DNES cells exist in the pregnant CL of dairy goats. Meanwhile, we identified the coding sequence of dairy goats NSE (GenBank Accession No. JN887466). Its nucleotide sequence homology was found to be 97.9%, 89.3%, 90% and 92.6%, respectively, compared with that of Bos taurus, Rattus norvegicus, Mus musculus and Homo sapiens, while the amino acid sequence homology was 99.1%, 97%, 97.2% and 98.2% respectively. These results first showed that the functional amino acids coded by the NSE gene were highly conserved in Caprine, B. taurus, R. norvegicus, M. musculus and H. sapiens. It was implied that the gene NSE in dairy goats had close homology to that of NSE of other species. Our findings demonstrated the possible existence of DNES cells in pregnant CL, providing new clue for further understanding of interactions between the neuroendocrine and reproductive systems. Characterization of gene sequence of dairy goats NSE will enable us to synthesize interference RNA for further study on the role of NSE on the formation, function and apoptosis of pregnant CL in dairy goats.

Localization of NSE protein in corpus luteum.(A) NSE immunoactive cell in corpus luteum (× 100).(B) Control for (A) without primary antibody (× 100).The present study provided the distribution of NSE in the pregnant CL of dairy goats, as NSE is a unique, generalized molecular marker for DNES cells, this result proved that many DNES cells exist in the pregnant CL of dairy goats.Figure optionsDownload high-quality image (321 K)Download as PowerPoint slideHighlights
► We provided the distribution of NSE in the pregnant CL of dairy goats.
► DNES cells were proved in pregnant CL of dairy goats for the first time.
► The gene NSE CDS of dairy goats was firstly identified in the present study.
► The gene NSE in dairy goats had close homology to that of NSE of other species.