Responses of blood parameters and hemoglobin subtypes in plateau zokors and plateau pikas to different altitude habitats.
- Author:
Cong-Hui GAO
1
;
Ji-Mei LI
2
;
Bo XU
3
;
Zhi-Fan AN
2
;
Zhi-Jie WANG
2
;
Xiao-Qi CHEN
2
;
Jia-Yu ZHANG
1
;
Deng-Bang WEI
1
Author Information
1. College of Ecological Environment Engineering, Qinghai University, Xining 810016, China.
2. State Key Laboratory of Plateau Ecology and Agriculture, Qinghai University, Xining 810016, China.
3. Key Laboratory of Adaptation and Evolution of Plateau Biota, Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China.
- Publication Type:Journal Article
- MeSH:
Animals;
Altitude;
Amino Acids;
Hemoglobins;
Hypoxia;
Lagomorpha
- From:
Acta Physiologica Sinica
2023;75(1):69-81
- CountryChina
- Language:Chinese
-
Abstract:
The plateau zokor (Myospalax baileyi) and plateau pika (Ochotona curzoniae) are native species unique to the Qinghai-Tibetan Plateau with successful adaptation to the hypoxic environment. In this study, the number of red blood cells, hemoglobin concentration, mean hematocrit and mean volume of red blood cells were measured in plateau zokors and plateau pikas at different altitudes. Hemoglobin subtypes of two plateau animals were identified by mass spectrometry sequencing. The forward selection sites in two animals' hemoglobin subunits were analyzed by PAML4.8 program. Homologous modeling was used to analyze the effect of forward selection sites on the affinity of hemoglobin to oxygen. The adapting strategies of plateau zokors and plateau pikas to hypoxia at different altitudes were analyzed through comparing blood parameters between the two species. The results indicated that, with increasing altitudes, plateau zokors responded to hypoxia by increasing red blood cell count and decreasing red blood cell volume, while plateau pikas took the opposite strategies to plateau zokors. In erythrocytes of plateau pikas, both adult α2β2 and fetal α2ε2 hemoglobins were identified, while erythrocytes of plateau zokors only had adult α2β2 hemoglobin, however the affinities and the allosteric effects of the hemoglobin of plateau zokors were significantly higher than those of plateau pikas. Mechanistically, in the α and β subunits of hemoglobin of plateau zokors and pikas, the numbers and the sites of the positively selected amino acids as well as the side chain groups polarities and orientations of the amino acids differed significantly, which may result in the difference of the affinities to oxygen of hemoglobin between plateau zokors and pikas. In conclusion, the adaptive mechanisms to respond to hypoxia in blood properties of plateau zokors and plateau pikas are species-specific.
