Characterization of the ATPase activity of human ATP-binding cassette transporter-2 (ABCA2).
In Vivo
; 19(4): 657-60, 2005.
Article
em En
| MEDLINE
| ID: mdl-15999530
ABSTRACT
BACKGROUND:
ABCA2 is a member of the ATP binding cassette transporter family with functional roles in cholesterol homeostasis and drug resistance. MATERIALS ANDMETHODS:
In order to characterize its ATPase activity, we transfected HEK293 cells with an ABCA2 mammalian expression system and isolated ABCA2-enriched membranes.RESULTS:
We found no measurable ATPase activity of ABCA2 in isolated membranes, except in the presence of the methyl-beta-cyclodextrin. However, competitive binding of a pseudo-substrate, 8-azido-[alpha-32P]-ATP, was demonstrated. CHO cells transfected with ABCA2 did not have a higher rate of endogenous ATP hydrolysis when compared to the mock-transfected cells.CONCLUSION:
Overall, we conclude that, while ABCA2 may have low levels of ATPase activity that can be substrate-stimulated, it is more likely to have a regulatory role in cell physiology.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Regulação Enzimológica da Expressão Gênica
/
Adenosina Trifosfatases
/
Transportadores de Cassetes de Ligação de ATP
Limite:
Animals
/
Humans
Idioma:
En
Revista:
In Vivo
Assunto da revista:
NEOPLASIAS
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Estados Unidos