Expression Analysis of PHD2 and Ang-1 in the Lungs of Yaks(Bos mutus)at Different Ages
Proline hydroxylase 2(PHD2)and angiopoietin 1(Ang-1)play an important role in animal adaptation to hypoxia and angiogenesis.In order to study the expression and distribution of PHD2 and Ang-1 in the lungs of yaks(Bos mutus)of different ages,and to explore its role in the formation of hypoxic adaptive structure in the lungs of yaks.In this study,3-day-old,6-month-old,3-year-old and 6-year-old yaks were used as research objects,and adult cattle(B.taurus)were selected as normoxic control.Immunohistochemical(IHC)staining,tissue immuno-fluorescence(IF)staining,qRT-PCR and Western blot were used to study the expression of PHD2 and Ang-1 in lung tissues of yaks and cattle of different ages.The results of IHC and IF showed that the expression sites of PHD2 and Ang-1 in yak and cattle were basically the same,mainly distributed in tracheal epithelial cells,tracheal glands,pulm-onary artery endothelial cells and alveolar epithelial cells.The results of qRT-PCR showed that the relative expression of PHD2 in yak group was significantly higher than that in cattle group,and that in 3-day-old yak group was significantly higher than that in other age groups(P<0.01).The relative expression of Ang-1 in yak group was significantly higher than that in cattle group,and that in 6-year-old yak group was significantly higher than that in other age groups(P<0.01).Western blot results showed that the relative expression of PHD2 protein in yak group was significantly higher than that in cattle group.With the increase of yak age,the relative expression of PHD2 protein decreased gradually.The relative expression of Ang-1 protein in the yak group was significantly higher than that in the cattle group,and the relative expression of Ang-1 protein gradually increased with the increase of yak age.In summary,PHD2 and Ang-1 play an important role in the adaptation of yak lungs to high altitude hypoxic environment.Both of them mainly act on lung epithelial cells and vascular endothelial cells,thereby maintaining the stability of normal breathing and pulmonary vascular function of yak lungs under hypoxic conditions.This study provides some basic data for further exploring the mechanism of hypoxia adaptability of yak lung in plateau environment.