Peptidyl-prolyl cis-trans isomerase A participates in the selenium transport into the rat brain.
J Biol Inorg Chem
; 26(8): 933-945, 2021 12.
Article
em En
| MEDLINE
| ID: mdl-34550449
ABSTRACT
Selenium, an essential micronutrient, plays vital roles in the brain. Selenoprotein P (SELENOP), a major plasma selenoprotein, is thought to transport selenium to the brain. However, Selenop-knockout mice fed a diet containing an adequate amount of selenium shows no objective neurological dysfunction which is observed in the selenium-deficient diet-fed Selenop-knockout mice. This fact indicated that selenium from low-mass selenium-source compounds can be transported by SELENOP-independent alternative pathways to the brain. In this study, to obtain the basic information about the SELENOP-independent transport pathways, we performed ex vivo experiments in which the rat brain cell membrane fraction was analyzed to find selenium-binding and/or -interactive proteins using its reactive metabolic intermediate, selenotrisulfide (STS), and MALDI TOF-mass spectrometry. Several membrane proteins with the cysteine (C) thiol were found to be reactive with STS through the thiol-exchange reaction. One of the C-containing proteins in the brain cell membrane fraction was identified as peptidyl-prolyl cis-trans isomerase (PPIase) A from tryptic fragmentation experiments and database search. Among the 4 C residues in rat PPIase A, 21st C was proved to react with STS by assessment using C mutated recombinant proteins. PPIase A is ubiquitously expressed and also associates with a variety of biologically important events such as immunomodulation, intracellular signaling, transcriptional regulation and protein trafficking. Consequently, PPIase A was thought to participate in the selenium transport into the rat brain.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Selênio
Limite:
Animals
Idioma:
En
Revista:
J Biol Inorg Chem
Assunto da revista:
BIOQUIMICA
Ano de publicação:
2021
Tipo de documento:
Article
País de afiliação:
Japão