Biomaterial Database

Stoichiometric analysis of internalization, recycling, and redistribution of photoaffinity-labeled guanylate cyclase/atrial natriuretic factor receptors in cultured murine Leydig tumor cells. 1993

K N Pandey

Department of Biochemistry and Molecular Biology, Medical College of Georgia, School of Medicine, Augusta 30912.

The membrane-bound form of guanylate cyclase represents a biologically active atrial natriuretic factor receptor (GC/ANF-R). Murine Leydig tumor (MA-10) cells predominantly overexpress GC/ANF-R in high density (Pandey, K. N., Pavlou, S. N., and Inagami, T. (1988) J. Biol. Chem. 263, 13406-13413; Pandey, K. N., and Singh, S. (1990) J. Biol. Chem. 265, 12342-12348). Information regarding the post-binding events of GC/ANF-R is obscure. This study presents the kinetics of internalization, recycling, and redistribution of GC/ANF-R in model MA-10 cells. Both the 125I-ANF binding assays and photoaffinity labeling procedures were utilized to label the total, intracellular, and cell surface GC/ANF-R. After the binding of 125I-ANF to GC/ANF-R, this complex was internalized and both the intact and degraded ligands were released into culture media. The distribution of 125I-ANF on the cell surface, in the intracellular compartments, and into culture media provided a dynamic relationship between the rates of 125I-ANF uptake, its degradation, and extrusion. The extent of receptor recycling was measured using tryptic proteolysis of photoaffinity-labeled GC/ANF-R to distinguish cell surface receptors from those that were internalized. A population of GC/ANF-R rapidly recycled (t1/2 = 5 min) from intracellular compartment to plasma membrane. Recycling of GC/ANF-R was impaired by chloroquine, dinitrophenol, and low temperature (22 degrees C). Furthermore, these studies suggest that dissociation of ANF from the receptor is not required for recycling of internalized GC/ANF-R.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D007984	Leydig Cell Tumor	Gonadal interstitial or stromal cell neoplasm composed of only LEYDIG CELLS. These tumors may produce one or more of the steroid hormones such as ANDROGENS; ESTROGENS; and CORTICOSTEROIDS. Clinical symptoms include testicular swelling, GYNECOMASTIA, sexual precocity in children, or virilization (VIRILISM) in females.	Interstitial Cell Tumor,Interstitial Cell Tumors,Tumor, Interstitial Cell,Tumor, Leydig Cell,Tumors, Interstitial Cell
D010777	Photochemistry	A branch of physical chemistry which studies chemical reactions, isomerization and physical behavior that may occur under the influence of visible and/or ultraviolet light.	Photochemistries
D002738	Chloroquine	The prototypical antimalarial agent with a mechanism that is not well understood. It has also been used to treat rheumatoid arthritis, systemic lupus erythematosus, and in the systemic therapy of amebic liver abscesses.	Aralen,Arechine,Arequin,Chingamin,Chlorochin,Chloroquine Sulfate,Chloroquine Sulphate,Khingamin,Nivaquine,Sulfate, Chloroquine,Sulphate, Chloroquine
D004705	Endocytosis	Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.	Endocytoses
D006162	Guanylate Cyclase	An enzyme that catalyzes the conversion of GTP to 3',5'-cyclic GMP and pyrophosphate. It also acts on ITP and dGTP. (From Enzyme Nomenclature, 1992) EC 4.6.1.2.	Guanyl Cyclase,Deoxyguanylate Cyclase,Guanylyl Cyclase,Inosinate Cyclase,Cyclase, Deoxyguanylate,Cyclase, Guanyl,Cyclase, Guanylate,Cyclase, Guanylyl,Cyclase, Inosinate
D006868	Hydrolysis	The process of cleaving a chemical compound by the addition of a molecule of water.
D000345	Affinity Labels	Analogs of those substrates or compounds which bind naturally at the active sites of proteins, enzymes, antibodies, steroids, or physiological receptors. These analogs form a stable covalent bond at the binding site, thereby acting as inhibitors of the proteins or steroids.	Affinity Labeling Reagents,Labeling Reagents, Affinity,Labels, Affinity,Reagents, Affinity Labeling
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014407	Tumor Cells, Cultured	Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.	Cultured Tumor Cells,Neoplastic Cells, Cultured,Cultured Neoplastic Cells,Cell, Cultured Neoplastic,Cell, Cultured Tumor,Cells, Cultured Neoplastic,Cells, Cultured Tumor,Cultured Neoplastic Cell,Cultured Tumor Cell,Neoplastic Cell, Cultured,Tumor Cell, Cultured