Cloning, Molecular Characterization and Tissue Differential Expression Analysis of PRL Gene in Dehong Dairy Buffalo

PurposeTo isolate and identify the prolactin (PRL) gene in Dehong dairy buffalo and to analyze its molecular characteristics and the expression of mRNA in different tissues.

MethodsThe complete coding sequence (CDS) of PRL gene of Dehong dairy buffalo was isolated and identified by PCR, and the molecular characteristics of buffalo PRL and the differential expression of PRL in lactation and non-lactation tissues were analyzed by bioinformatics and semi-quantitative RT-PCR, respectively.

ResultsThe CDS of PRL gene of buffalo is 690 bp in length and encoded 229 amino acids. The buffalo PRL protein is a hydrophilic secretory protein with no transmembrane structural domain, containing a signal peptide sequence region (AA1-30), five types of functional modifier sites and a prolactin_like structural domain (AA32-229), and participates in JAK-STAT and PI3K-AKT-mTOR signal pathways. The transcriptional region structure of PRL and the structure and conserved structural domains of its encoded protein were consistent in the species of Bovidae. The buffalo PRL gene is expressed in all 11 tissues detected, and the expression in mammary gland during lactation period is extremely significantly higher than that in non-lactation period (P<0.001).

ConclusionThe function of buffalo PRL is highly consistent with that of other species of Bovidae. The PRL participates in JAK-STAT and PI3K-AKT-mTOR milk protein synthesis signaling pathways, and buffalo PRL plays a role in various tissues including mammary gland and lung, so it is speculated that it participates in buffalo milk protein and milk fat synthesis.