Subcellular localization of cytochrome b and ubiquinone in a tertiary granule of resting human neutrophils and evidence for a proton pump ATPase - PubMed (original) (raw)

. 1984 Jun 10;259(11):7143-50.

PMID: 6144682

Free article

Subcellular localization of cytochrome b and ubiquinone in a tertiary granule of resting human neutrophils and evidence for a proton pump ATPase

F Mollinedo et al. J Biol Chem. 1984.

Free article

Abstract

The subcellular distribution of cytochrome b and ubiquinone in resting human neutrophils was investigated by rate zonal sedimentation of postnuclear supernatants on continuous sucrose gradients. Both cytochrome b and ubiquinone were mainly localized in small organelles, tertiary granules, that were resolved from the specific and azurophilic granules as well as from the cell membrane fraction. This cytochrome b- and ubiquinone-rich granule was shown to contain dicyclohexylcarbodiimide (DCCD)-sensitive, Mg2+-dependent ATPase as well as low amounts, less than a third, of the acid hydrolases beta-glucuronidase and N-acetyl-beta-glucosaminidase. Cytochrome b was also found in smaller proportions in plasma membranes and specific granules. A significant proportion of the ubiquinone was located in the region of the gradients where specific granules and mitochondria sedimented. However, quantitative measurements of oligomycin-sensitive ATPase indicated that this second localization of ubiquinone could not be entirely attributed to mitochondrial contamination. Plasma membrane contained small amounts of ubiquinone. In addition, the existence and location of a putative proton pump ATPase were also investigated. The ATPase was mainly located in the plasma membrane and in the upper half of the gradients (tertiary and specific granules), with the highest specific activity occurring in the tertiary granules. This activity was inhibited by 100 microM DCCD. Furthermore, ATP-dependent uptake of [14C]methylamine by tertiary and specific granules was observed. These results suggest that the DCCD-sensitive ATPase may function as a proton pump. DCCD inhibited the release of enzymes from specific granules that occurred when human neutrophils were activated by phorbol myristate acetate. However, higher concentrations of DCCD were required to achieve the same degree of inhibition of O2 uptake (I50 of 0.4 mM for secretion versus 1 mM for O2 uptake). These results suggest that specific granules do not play a crucial role in oxygen metabolism.

PubMed Disclaimer

Cited by

Modulation of Early Neutrophil Granulation: The Circulating Tumor Cell-Extravesicular Connection in Pancreatic Ductal Adenocarcinoma.
Charles Jacob HK, Charles Richard JL, Signorelli R, Kashuv T, Lavania S, Vaish U, Boopathy R, Middleton A, Boone MM, Sundaram R, Dudeja V, Saluja AK. Charles Jacob HK, et al. Cancers (Basel). 2021 May 31;13(11):2727. doi: 10.3390/cancers13112727. Cancers (Basel). 2021. PMID: 34072942 Free PMC article.
Subcellular localization and dynamics of components of the respiratory burst oxidase.
Borregaard N. Borregaard N. J Bioenerg Biomembr. 1988 Dec;20(6):637-51. doi: 10.1007/BF00762546. J Bioenerg Biomembr. 1988. PMID: 2854126 Review.
Major co-localization of the extracellular-matrix degradative enzymes heparanase and gelatinase in tertiary granules of human neutrophils.
Mollinedo F, Nakajima M, Llorens A, Barbosa E, Callejo S, Gajate C, Fabra A. Mollinedo F, et al. Biochem J. 1997 Nov 1;327 ( Pt 3)(Pt 3):917-23. doi: 10.1042/bj3270917. Biochem J. 1997. PMID: 9581574 Free PMC article.
Cytochrome b co-fractionates with gelatinase-containing granules in human neutrophils.
Mollinedo F, Gajate C, Schneider DL. Mollinedo F, et al. Mol Cell Biochem. 1991 Jun 26;105(1):49-60. doi: 10.1007/BF00230374. Mol Cell Biochem. 1991. PMID: 1656202

Subcellular localization of cytochrome b and ubiquinone in a tertiary granule of resting human neutrophils and evidence for a proton pump ATPase - PubMed (original) (raw)