Abstract
Background: ABCA2 is a member of the ATP binding cassette transporter family with functional roles in cholesterol homeostasis and drug resistance. Materials and methods: 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-β-cyclodextrin. However, competitive binding of a pseudo-substrate, 8-azido-[α-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.
Original language | English (US) |
---|---|
Pages (from-to) | 657-660 |
Number of pages | 4 |
Journal | In Vivo |
Volume | 19 |
Issue number | 4 |
State | Published - Jul 2005 |
Externally published | Yes |
Keywords
- ABCA2 transporter
- ATPase activity
- Catalysis
- Pseudo-substrate
ASJC Scopus subject areas
- Medicine(all)