摘要
All organisms respond to variation in their environments and manage environmental stress through metabolic adjustments.The plateau zokor(Myospalax baileyi) is an endemic and keystone subterranean rodent species that inhabits the Qinghai-Tibet Plateau between 2800 and 4200 m above sea level.It is a hypoxic-tolerant mammal with a high ratio of oxygen utilization that enables it to cope with its harsh surroundings.To explore the molecular mechanism of altitude acclimatization of the plateau zokor,we cloned the zokor erythropoietin(Epo) gene and used real-time PCR to compare Epo mRNA levels in zokors inhabiting 16 different altitudes.The full-length zokor Epo open reading frame was 579 bp that encoded a precursor peptide of 192 amino acids with a signal peptide of 26 residues.The Epo gene of the plateau zokor was 81%-95% homologous to that of human,mouse,rat,root vole and the Golan Heights blind mole rat,with the highest homology(95%) to species of the genus Spalax.Epo mRNA was detected mainly in the zokor kidney and spleen among 8 selected tissues.The level of Epo mRNA increased in the liver and kidney with increases in altitude.The increase in the kidney was 5 times that in the liver.Remarkably,expression of Epo mRNA in the kidney of zokors living at the highest altitude(4268 m) was 12-fold higher than that of zokors living at the lowest(2492 m) altitude.These findings provide essential information for understanding the possible role of Epo in adaptation to hypoxia in the plateau zokor.
All organisms respond to variation in their environments and manage environmental stress through metabolic adjustments. The plateau zokor （Myospalax baileyi） is an endemic and keystone subterranean rodent species that inhabits the Qinghai-Tibet Plateau between 2800 and 4200 m above sea level. It is a hypoxic-tolerant mammal with a high ratio of oxygen utilization that enables it to cope with its harsh surroundings. To explore the molecular mechanism of altitude acclimatization of the plateau zokor, we cloned the zokor erythropoietin （Epo） gene and used real-time PCR to compare Epo mRNA levels in zokors inhabiting 16 differ- ent altitudes. The full-length zokor Epo open reading frame was 579 bp that encoded a precursor peptide of 192 amino acids with a signal peptide of 26 residues. The Epo gene of the plateau zokor was 81%-95% homologous to that of human, mouse, rat, root vole and the Golan Heights blind mole rat, with the highest homology （95%） to species of the genus Spalax. Epo mRNA was detected mainly in the zokor kidney and spleen among 8 selected tissues. The level of Epo mRNA increased in the liver and kid- ney with increases in altitude. The increase in the kidney was 5 times that in the liver. Remarkably, expression of Epo mRNA in the kidney of zokors living at the highest altitude （4268 m） was 12-fold higher than that of zokors living at the lowest （2492 m） altitude. These findings provide essential information for understanding the possible role of Epo in adaptation to hypoxia in the plateau zokor.
基金
supported by Key Innovation Research Program,Chinese Academy of Sciences (KSCX2-EW-N-05)
the National Basic Research Program of China (2012CB722506)
the Key Projects in the Nationa Science & Technology Pillar Program (2009BAI83B01)
