Selenium-containing proteins of rat kidney and liver microsomes

Journal Article · Fri Dec 01 00:00:00 EST 1989 · Journal of Inorganic Biochemistry; (USA)

DOI:https://doi.org/10.1016/0162-0134(89)85004-4· OSTI ID:6918939

Viljoen, A J; Motchnik, P A; Tappel, A L ^[1]

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1. Univ. of California, Davis (USA)

Selenium (Se)-containing proteins in microsomal fractions of rat kidney and liver were investigated after isotopic labeling of rats with ({sup 75}Se)selenite. More than 85% of the {sup 75}Se in the solubilized microsomal extracts precipitated with protein after trichloroacetic acid treatment. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), used to separate the labeled protein subunits in the solubilized microsomal extracts, revealed several {sup 75}Se-containing proteins in addition to glutathione peroxidase. {sup 75}Se-labeled subunits with molecular weights of 55, 30, 26, 22, 19, and 17 kDa were present in microsomal fractions of kidney and liver. The {sup 75}Se-labeled tryptic peptide of the 55 kDa subunit had the same Rf value on a 17% SDS-PAGE gel as the peptide from plasma selenoprotein P. A time-course study of the labeling of individual protein subunits in kidney and liver microsomes from Se-supplemented and Se-deficient rats showed that most of the {sup 75}Se was associated with the 55 kDa subunit 3 hr after injection. The amount of {sup 75}Se associated with this protein subunit decreased by 12 hr, with a concurrent increase in the labeling of lower molecular-weight subunits. The results support the hypothesis that there is a mechanism for transfer of Se from the 55 kDa subunit to other Se-containing proteins.

• OSTI ID: 6918939
• Journal Information: Journal of Inorganic Biochemistry; (USA), Vol. 37:4; ISSN 0162-0134
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
METALLOPROTEINS
LABELLING
SELENIUM
METABOLISM
ELECTROPHORESIS
GLUTATHIONE
ION EXCHANGE CHROMATOGRAPHY
KIDNEYS
LIVER
MICROSOMES
MOLECULAR WEIGHT
PEROXIDASES
RATS
SELENIUM 75
TRACER TECHNIQUES
ANIMALS
BETA DECAY RADIOISOTOPES
BODY
CELL CONSTITUENTS
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
ENZYMES
EVEN-ODD NUCLEI
GLANDS
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
NUCLEI
ORGANIC COMPOUNDS
ORGANOIDS
ORGANS
OXIDOREDUCTASES
PEPTIDES
POLYPEPTIDES
PROTEINS
RADIOISOTOPES
RADIOPROTECTIVE SUBSTANCES
RIBOSOMES
RODENTS
SELENIUM ISOTOPES
SEMIMETALS
SEPARATION PROCESSES
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology
550501 - Metabolism- Tracer Techniques