Hemoglobins play a key role in oxygen transport. High-oxygen-affinity hemoglobins are adaptive in hypoxic environments. To better understand adaptation to high-altitude hypoxia, we extracted RNA from the bone marrow of six Crested Ducks (Lophonetta specularioides) inhabiting the central high Andes of Peru (4,218–4,605 m elevation) and sequenced >2,000 expressed sequence tags (EST) from a non-normalized complementary-DNA (cDNA) library. Overall, we identified 1,692 ESTs in the expression profile representing 462 different genes. Among those, the ESTs that occurred at the highest frequency were the αA (major) hemoglobin subunit (HBA2; 22.7%), leukocyte cell-derived chemotaxin 2 (LECT2; 10%), αD (minor) hemoglobin subunit (HBA1; 9.6%), beta defensins (DEFB; 6.3%), and the βA hemoglobin subunit (HBB; 3.7%). These results provide the first quantitative identification of gene expression in bone marrow of individuals inhabiting high-altitude regions and are in agreement with the known hemopoietic and immune function of this tissue. The EST sequences identified here will be useful for a variety of studies focusing on other nontraditional model organisms. Further studies of Crested Ducks and other highland taxa will be required to determine whether the αA and αD hemoglobin subunits, which contribute to distinct isoforms with potentially different oxygen-binding properties, are differentially expressed in lowland and highland populations.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 126 • No. 3