Cavefish cope with environmental hypoxia by developing more erythrocytes and overexpression of hypoxia-inducible genes

eLife

William R Jeffery¹  Corine M van der Weele¹ 

[1] Department of Biology, University of Maryland, College Park, United States;

关键词: hypoxia;    evolution;    cavefish;    hypoxia-inducible factor genes;    erythrocytes;    hematopoiesis;    Other;   

DOI  :  10.7554/eLife.69109

来源: eLife Sciences Publications, Ltd

【 摘 要 】

Dark caves lacking primary productivity can expose subterranean animals to hypoxia. We used the surface-dwelling (surface fish) and cave-dwelling (cavefish) morphs of Astyanax mexicanus as a model for understanding the mechanisms of hypoxia tolerance in the cave environment. Primitive hematopoiesis, which is restricted to the posterior lateral mesoderm in other teleosts, also occurs in the anterior lateral mesoderm in Astyanax, potentially pre-adapting surface fish for hypoxic cave colonization. Cavefish have enlarged both hematopoietic domains and develop more erythrocytes than surface fish, which are required for normal development in both morphs. Laboratory-induced hypoxia suppresses growth in surface fish but not in cavefish. Both morphs respond to hypoxia by overexpressing hypoxia-inducible factor 1 (hif1) pathway genes, and some hif1 genes are constitutively upregulated in normoxic cavefish to similar levels as in hypoxic surface fish. We conclude that cavefish cope with hypoxia by increasing erythrocyte development and constitutive hif1 gene overexpression.

【 授权许可】

CC BY