Biomaterial Database

Species specificity of transferrin binding, endocytosis and iron internalization by cultured chick myogenic cells. 1988

L M Sorokin, and E H Morgan

Department of Physiology, University of Western Australia, Nedlands.

The ability of unlabelled heterologous transferrin to interact with transferrin receptors on developing chick myogenic cells was investigated by measuring their capacity to inhibit the surface-binding and internalization of 125I- and 59Fe-labelled ovotransferrin. Transferrins from rat, rabbit, human, and a species of kangaroo (Macropus fuliginosus) were unable to inhibit either surface-binding or internalization of labelled ovotransferrin even at concentrations ten times the molar concentration of the ovotransferrin. Transferrins isolated from the serum of a toad (Bufo marinus) and a lizard (Teliqua rugosa), when added at high concentrations, were found to reduce surface-binding of 125I-Tf by 20-25% but did not inhibit internalization of either 125I-Tf or 59Fe. This suggests that the effects of toad and lizard transferrins are due to non-specific binding to the myogenic cells. In contrast, inhibition of both surface-binding and internalization of labelled ovotransferrin was found when myogenic cells were incubated in the presence of the homologous transferrin (ovotransferrin). The species-specificity of transferrin binding, endocytosis and iron internalization did not vary with the state of proliferation or differentiation of the myogenic cells. However, the intracellular iron utilization was found to differ between differentiating presumptive and terminally differentiated myotubes. Internalized 59Fe was fractioned by gel filtration. In dividing and non-dividing presumptive myoblasts 59Fe was found to elute in three peaks, two with elution volumes corresponding to ferritin and transferrin and one at greater elution volume than that of myoglobin.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D007501	Iron	A metallic element with atomic symbol Fe, atomic number 26, and atomic weight 55.85. It is an essential constituent of HEMOGLOBINS; CYTOCHROMES; and IRON-BINDING PROTEINS. It plays a role in cellular redox reactions and in the transport of OXYGEN.	Iron-56,Iron 56
D009132	Muscles	Contractile tissue that produces movement in animals.	Muscle Tissue,Muscle,Muscle Tissues,Tissue, Muscle,Tissues, Muscle
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D002455	Cell Division	The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.	M Phase,Cell Division Phase,Cell Divisions,Division Phase, Cell,Division, Cell,Divisions, Cell,M Phases,Phase, Cell Division,Phase, M,Phases, M
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D002642	Chick Embryo	The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.	Embryo, Chick,Chick Embryos,Embryos, Chick
D004705	Endocytosis	Cellular uptake of extracellular materials within membrane-limited vacuoles or microvesicles. ENDOSOMES play a central role in endocytosis.	Endocytoses
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
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding
D013045	Species Specificity	The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.	Species Specificities,Specificities, Species,Specificity, Species