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Development and Identification of a Novel Subpopulation of Human Neutrophil-derived Giant Phagocytes In Vitro
Published on: January 25, 2017
Localization of cyclic GMP-dependent protein kinase in human mononuclear phagocytes
K B Pryzwansky1, S Kidao, T A Wyatt
1Department of Pathology, University of North Carolina, Chapel Hill 27599-7525, USA.
Journal of Leukocyte Biology
|April 1, 1995
Summary
Cyclic GMP-dependent protein kinase (G-kinase) is present in human immune cells. This kinase plays a role in protein processing and cell motility, particularly during macrophage adherence and spreading.
Area of Science:
- Immunology
- Cell Biology
- Biochemistry
Background:
- Cyclic GMP-dependent protein kinase (G-kinase) is a key signaling molecule.
- Its presence and function in human mononuclear phagocytes, such as monocytes and macrophages, are not well-defined.
Purpose of the Study:
- To investigate the presence and physiological role of G-kinase in human mononuclear phagocytes.
- To determine the subcellular localization of G-kinase in different types of human phagocytes.
Main Methods:
- Western blotting to detect G-kinase protein.
- Immunofluorescence microscopy and dual-label confocal laser scanning microscopy for subcellular localization.
- Treatment with cytochalasin D, nocodazole, and the guanylate cyclase inhibitor LY83583.
Main Results:
- G-kinase was detected in human monocytes, monocyte-derived macrophages, and alveolar macrophages.
- G-kinase localized to various cellular compartments including granules, vesicles, the Golgi, endoplasmic reticulum, nucleus, and cell periphery.
- G-kinase targeting to the cell periphery during adherence was dependent on actin filaments and inhibited by LY83583, suggesting a role in cell spreading.
Conclusions:
- G-kinase is present and physiologically relevant in human mononuclear phagocytes.
- G-kinase is involved in cGMP-mediated regulation of protein processing and cell motility.
- Its localization at the cell periphery suggests a role in regulating cell shape and movement during adhesion.
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