Comprehensive Analysis of Porcine Prox1 Gene and Its Relationship with Meat Quality Traits

SIMPLE SUMMARY: The improvement of porcine meat quality is one of the most challenging tasks in pig breeding. The identification and utilization of major genes and variations affecting meat quality traits has become a research hotspot in molecular breeding of pigs. In this study, we analyzed the characteristics of porcine Prospero-related homeobox 1 (Prox1) gene to lay a solid foundation for further functional study. The expression pattern of Prox1, as well as the correlation and association analysis of Prox1 with meat quality traits, indicates that Prox1 can be targeted to improve porcine meat quality traits. ABSTRACT: Prox1 is involved in muscle fiber conversion, adult-onset obesity, and type 2 diabetes. However, information regarding porcine Prox1 and its relationship with meat quality traits is still unknown. In this study, we characterized the full-length cDNA and proximal promoter of two transcript variants of porcine Prox1. Moreover, Prox1 was expressed abundantly in the skeletal muscle and its expression was higher in the soleus muscle than that in the biceps femoris muscle. Its expression pattern in the high and low meat color (redness) value a* groups was similar to that of myoglobin and MyHC I, but opposed to that of MyHC IIB. Importantly, there was a significant positive correlation between Prox1 expression and meat color (redness) value a* (r = 0.3845, p = 0.0394), and a significant negative correlation between Prox1 expression and drip loss (r = −0.4204, p = 0.0232), as well as the ratio of MyHC IIB to MyHC I expression (r = −0.3871, p = 0.0380). In addition, we found that the polymorphisms of three closely linked SNPs in Prox1 promoter 1 were significantly associated with pH(24h) in a pig population. Taken together, our data provide valuable insights into the characteristics of porcine Prox1 and indicate that Prox1 is a promising candidate gene affecting meat quality traits.