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Atomic Absorbance Spectroscopy to Measure Intracellular Zinc Pools in Mammalian Cells
Published on: May 16, 2019
Reduced reliance on the trace element selenium during evolution of mammals
Alexey V Lobanov1, Dolph L Hatfield, Vadim N Gladyshev
1Department of Biochemistry, University of Nebraska, Lincoln, NE 68588, USA. lobanov@genomics.unl.edu
Genome Biology
|April 2, 2008
Summary
Mammals evolved reduced reliance on selenium (Se), decreasing its use in proteins like Selenoprotein P (SelP) compared to fish. This evolutionary shift impacts dietary Se needs and supplementation practices.
Area of Science:
- Biochemistry
- Evolutionary Biology
- Trace Element Metabolism
Background:
- Selenium (Se) is vital, incorporated into proteins as selenocysteine (Sec).
- Selenoprotein P (SelP) transports Se and is a potential marker for dietary Se status.
Purpose of the Study:
- Investigate the evolutionary origins and changes in Selenoprotein P (SelP).
- Analyze the evolutionary trajectory of selenium utilization in vertebrates.
Main Methods:
- Comparative evolutionary analysis of Selenoprotein P (SelP) domains.
- Reconstruction of evolutionary changes in Sec content.
- Comparison of Se utilization between mammalian and fish lineages.
Main Results:
- SelP's amino-terminal domain relates to bacterial thiol oxidoreductases; the carboxy-terminal domain evolved in metazoans.
- Mammalian evolution shows a decrease in Sec content in SelP, with replacement by cysteine (Cys).
- Fish exhibit higher SelP Sec content, larger selenoproteomes, and greater Se levels than mammals, which have lost selenoproteins and replaced Sec with Cys.
Conclusions:
- Vertebrate evolution from fish to mammals involved reduced Se utilization, marked by Sec/Cys transitions in SelP.
- Reduced reliance on Se challenges the necessity of maximizing selenoprotein expression via Se supplements when not clinically indicated.
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