The Arachidonate-activable, NADPH Oxidase-associated H
Channel
EVIDENCE THAT gp91-phox FUNCTIONS AS AN ESSENTIAL PART OF THE CHANNEL (*)
- From the Department of Biochemistry, School of Medical Sciences, University of Bristol, University Walk, Bristol, BS8 1TD, United Kingdom
- § To whom correspondence should be addressed. Tel.: 117-9287437; Fax: 117-9288274; L.M.Henderson{at}bristol.ac.uk
Abstract
The human neutrophil NADPH oxidase-associated H
channel acts as a charge compensator for the electrogenic generation of superoxide (O
2). The expression of the channel activity was found to increase in parallel with that of the stimulatable generation of O
2 in differentiated HL60 cells. HL60 cells induced to differentiate in the presence of succinyl acetone (a inhibitor of heme
synthesis) were unable to generate O
2, failed to express p22-phox but retained H
channel activity. EBV transformed B lymphocyte cell lines from normal and CGD patients lacking expression of either p47-phox or p67-phox all expressed unaltered channel activity; however, the activity was completely absent in the lymphocyte cell line lacking
gp91-phox. CHO cells and undifferentiated HL60 cells transfected with gp91-phox cDNA expressed H
channel activity correlating with the expression of gp91-phox. We therefore conclude that the large subunit of the NADPH oxidase cytochrome b (gp91-phox) is the arachidonate activable H
channel of human neutrophils.
Footnotes
-
↵* This work was supported by a grant from the Arthritis and Rheumatism Council, United Kingdom. The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore by hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
-
↵1 The abbreviations used are:
- CCCP
-
carbonyl cyanide m-chlorophenyl-hydrazone
- AA
-
arachidonate
- BCECF-AM
-
biscarboxyl 5 (and 6)-carboxyfluorescence acetomethyl ester
- CHO
-
Chinese hamster ovary
- CGD
-
chronic grandulomatous disease
- DMF
-
dimethylformamide
- EBV
-
Epstein-Barr virus
- FCS
-
fetal calf serum
- HL60
-
human leukemic 60 cell line
- SA
-
succinyl acetone-4,6-dioxoheptanoic acid.
-
- Received October 18, 1994.
- Revision received December 16, 1994.
- © 1995 by The American Society for Biochemistry and Molecular Biology, Inc.
