Negative regulation of the creatine transporter SLC6A8 by SPAK and OSR1.
Kidney Blood Press Res
; 39(6): 546-54, 2014.
Article
em En
| MEDLINE
| ID: mdl-25531585
ABSTRACT
BACKGROUND/AIMS:
Transport regulation involves several kinases including SPAK (SPS1-related proline/alanine-rich kinase) and OSR1 (oxidative stress-responsive kinase 1), which are under control of WNK (with-no-K[Lys]) kinases. The present study explored whether SPAK and/or OSR1 participate in the regulation of the creatine transporter CreaT (SLC6A8), which accomplishes Na+ coupled cellular uptake of creatine in several tissues including kidney, intestine, heart, skeletal muscle and brain.METHODS:
cRNA encoding SLC6A8 was injected into Xenopus laevis oocytes with or without additional injection of cRNA encoding wild-type SPAK, constitutively active (T233E)SPAK, WNK insensitive (T233A)SPAK, catalytically inactive (D212A)SPAK, wild-type OSR1, constitutively active (T185E)OSR1, WNK insensitive (T185A)OSR1 and catalytically inactive (D164A)OSR1. Transporter activity was determined from creatine (1 mM) induced current utilizing dual electrode voltage clamp.RESULTS:
Coexpression of wild-type SPAK and of (T233E)SPAK, but not of (T233A)SPAK or of (D212A)SPAK was followed by a significant decrease of creatine induced current in SLC6A8 expressing oocytes. Coexpression of SPAK significantly decreased maximal transport rate. Coexpression of wild-type OSR1, (T185E)OSR1 and (T185A)OSR1 but not of (D164A)OSR1 significantly negatively regulated SLC6A8 activity. OSR1 again decreased significantly maximal transport rate.CONCLUSIONS:
Both, SPAK and OSR1, are negative regulators of the creatine transporter SLC6A8.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas Serina-Treonina Quinases
/
Proteínas da Membrana Plasmática de Transporte de Neurotransmissores
/
Proteínas do Tecido Nervoso
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article