气候变化领域集成服务门户(CCPortal): Evolved increases in hemoglobin-oxygen affinity and the Bohr effect coincided with the aquatic specialization of penguins

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DOI	10.1073/pnas.2023936118
	Evolved increases in hemoglobin-oxygen affinity and the Bohr effect coincided with the aquatic specialization of penguins
	Signore A.V.; Tift M.S.; Hoffmann F.G.; Schmitt T.L.; Moriyama H.; Storz J.F.
发表日期	2021
ISSN	00278424
卷号	118 期号:13
英文摘要	Dive capacities of air-breathing vertebrates are dictated by onboard O2 stores, suggesting that physiologic specialization of diving birds such as penguins may have involved adaptive changes in convective O2 transport. It has been hypothesized that increased hemoglobin (Hb)-O2 affinity improves pulmonary O2 extraction and enhances the capacity for breath-hold diving. To investigate evolved changes in Hb function associated with the aquatic specialization of penguins, we integrated comparative measurements of whole-blood and purified native Hb with protein engineering experiments based on site-directed mutagenesis. We reconstructed and resurrected ancestral Hb representing the common ancestor of penguins and the more ancient ancestor shared by penguins and their closest nondiving relatives (order Procellariiformes, which includes albatrosses, shearwaters, petrels, and storm petrels). These two ancestors bracket the phylogenetic interval in which penguin-specific changes in Hb function would have evolved. The experiments revealed that penguins evolved a derived increase in Hb-O2 affinity and a greatly augmented Bohr effect (i.e., reduced Hb-O2 affinity at low pH). Although an increased Hb-O2 affinity reduces the gradient for O2 diffusion from systemic capillaries to metabolizing cells, this can be compensated by a concomitant enhancement of the Bohr effect, thereby promoting O2 unloading in acidified tissues. We suggest that the evolved increase in Hb-O2 affinity in combination with the augmented Bohr effect maximizes both O2 extraction from the lungs and O2 unloading from the blood, allowing penguins to fully utilize their onboard O2 stores and maximize underwater foraging time. © 2021 National Academy of Sciences. All rights reserved.
英文关键词	Adaptation; Bohr effect; Hemoglobin; Hypoxia; Penguins
语种	英语
scopus关键词	hemoglobin; oxygen; adaptation; aquatic species; Article; binding affinity; Bohr effect; ecological specialization; evolution; hypoxia; nonhuman; oxygen diffusion; penguin; phylogeny; priority journal; protein function
来源期刊	Proceedings of the National Academy of Sciences of the United States of America
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/180076
作者单位	School of Biological Sciences, University of Nebraska, Lincoln, NE 68588, United States; Department of Biology and Marine Biology, University of North Carolina, Wilmington, NC 28403, United States; Department of Biochemistry, Molecular Biology, Entomology, and Plant Pathology, Mississippi State University, Starkville, MS 39762, United States; Institute for Genomics,, Biocomputing and Biotechnology, Mississippi State University, Starkville, MS 39762, United States; Veterinary Services, SeaWorld of California, San Diego, CA 92109, United States
推荐引用方式 GB/T 7714	Signore A.V.,Tift M.S.,Hoffmann F.G.,et al. Evolved increases in hemoglobin-oxygen affinity and the Bohr effect coincided with the aquatic specialization of penguins[J],2021,118(13).
APA	Signore A.V.,Tift M.S.,Hoffmann F.G.,Schmitt T.L.,Moriyama H.,&Storz J.F..(2021).Evolved increases in hemoglobin-oxygen affinity and the Bohr effect coincided with the aquatic specialization of penguins.Proceedings of the National Academy of Sciences of the United States of America,118(13).
MLA	Signore A.V.,et al."Evolved increases in hemoglobin-oxygen affinity and the Bohr effect coincided with the aquatic specialization of penguins".Proceedings of the National Academy of Sciences of the United States of America 118.13(2021).