Selenium incorporation into selenoproteins in the Se-adequate and Se-deficient rat

Journal Article · Mon Feb 01 04:00:00 EST 1988 · Proc. Soc. Exp. Biol. Med.; (United States)

DOI:https://doi.org/10.3181/00379727-187-42651· OSTI ID:5313706

Evenson, J K; Sunde, R A

To rapidly discriminate between selenoproteins and Se-binding proteins, SDS + 2-mercaptoethanol treatment and then gradient SDS-slab gel electrophoresis was used to remove loosely bound Se from proteins while separating protein subunits according to molecular weight. This technique was used to study the nature and time course of /sup 75/Se incorporation into selenoproteins. Male weanling rats were fed either a Se-adequate (0.35 ppm Se) or a Se-deficient (less than 0.02 ppm Se) diet for 20-41 days, injected iv with 50 microCi (/sup 75/Se)selenite (100 microCi/micrograms Se), and sacrificed 1, 3, 24, or 72 hr after /sup 75/Se injection. At 1 and 3 hr, a 55-kDa plasma /sup 75/Se protein contained the most /sup 75/Se of any /sup 75/Se protein observed in any tissue in either Se-adequate or Se-deficient rats. At 24 and 72 hr, a 23-kDa /sup 75/Se protein (glutathione peroxidase subunit) in liver cytosol was the second-most labeled /sup 75/Se protein observed in Se-adequate rats. The second-most labeled /sup 75/Se protein in Se-deficient rats was a 17-kDa /sup 75/Se protein in testes at 24 and 72 hr. /sup 75/Se proteins of 10, 14, 45, and 65 kDa as well as lesser amounts of other /sup 75/Se proteins were also detected. In a separate experiment, cycloheximide pretreatment eliminated /sup 75/Se labeling of any of the /sup 75/Se proteins, demonstrating that protein synthesis is required for Se incorporation. The rise and fall of various /sup 75/Se proteins with time suggests that these seleno-proteins may be important in the flux of Se between tissues.

• Research Organization: Univ. of Arizona, Tucson (USA)
• OSTI ID: 5313706
• Journal Information: Proc. Soc. Exp. Biol. Med.; (United States), Journal Name: Proc. Soc. Exp. Biol. Med.; (United States) Vol. 187:2; ISSN PSEBA
• Country of Publication: United States
• Language: English

Related Subjects

550501 -- Metabolism-- Tracer Techniques
560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
BETA DECAY RADIOISOTOPES
BODY
CARDIOVASCULAR SYSTEM
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DISTRIBUTION
ELECTRON CAPTURE RADIOISOTOPES
ELECTROPHORESIS
ELEMENTS
EVEN-ODD NUCLEI
GLANDS
HEART
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
LIVER
MAMMALS
METABOLISM
MOLECULAR WEIGHT
MUSCLES
MYOCARDIUM
NUCLEI
NUTRITIONAL DEFICIENCY
ORGANS
RADIOISOTOPES
RATS
RODENTS
SELENIUM
SELENIUM 75
SELENIUM ISOTOPES
SEMIMETALS
TISSUE DISTRIBUTION
TRACER TECHNIQUES
VERTEBRATES