The Interaction of Iron-Conalbumin(Anion) Complexes with Chick Embryo Red Blood Cells

Williams, Susan; Woodworth, Robert C.

doi:10.1016/s0021-9258(19)43580-1

Cited by 52 publications

(15 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The level of expression of wild-type and mutant human TRs on infected CEF varied from 3.6-7.7 x 105 molecules/cell, with dissociation constants for the binding of human Tf ranging from 3.6-8.7 nM (Table I). About 105 chicken TRs were expressed on infected and uninfected CEF with a dissociation constant for the binding of ovotransferrin of ,,o100 nM, which is similar to previously reported values (Williams and Woodworth, 1973;Schmidt et al, 1986;Sorokin et al, 1987). Uninfected CEF did not bind human "If.…”

Section: Resultssupporting

confidence: 82%

Role of the human transferrin receptor cytoplasmic domain in endocytosis: localization of a specific signal sequence for internalization.

Jing

Spencer

Miller

et al. 1990

The Journal of Cell Biology

300

190

View full text Add to dashboard Cite

Abstract. Wild-type and mutant human transferrin receptors have been expressed in chicken embryo fibroblasts using a helper-independent retroviral vector. The internalization of mutant human transferrin receptors, in which all but four of the 61 amino acids of the cytoplasmic domain had been deleted, was greatly impaired. However, when expressed at high levels, such "tailless" mutant receptors could provide chicken embryo fibroblasts with sufficient iron from diferric human transferrin to support a normal rate of growth. As the rate of recycling of the mutant receptors was not significantly different from wild-type receptors, an estimate of relative internalization rates could be obtained from the distribution of receptors inside the cell and on the cell surface under steady-state conditions. This analysis and the results of iron uptake studies both indicate that the efficiency of internalization of tailless mutant receptors is *10% that of wild-type receptors. Further studies of a series of mutant receptors with different regions of the cytoplasmic domain deleted suggested that residues within a 10-amino acid region (amino acids 19-28) of the human transferrin receptor cytoplasmic domain are required for efficient endocytosis. Insertion of this region into the cytoplasmic domain of the tailless mutant receptors restored high efficiency endocytosis. The only tyrosine residue (Tyr 20) in the cytoplasmic domain of the human transferrin receptor is found within this 10-amino acid region. A mutant receptor containing glycine instead of tyrosine at position 20 was estimated to be •20 % as active as the wild-type receptor. We conclude that the cytoplasmic domain of the transferrin receptor contains a specific signal sequence located within amino acid residues 19-28 that determines high efficiency endocytosis. Further, Tyr 20 is an important element of that sequence.

show abstract

Section: Resultssupporting

confidence: 82%

Role of the human transferrin receptor cytoplasmic domain in endocytosis: localization of a specific signal sequence for internalization.

Jing

Spencer

Miller

et al. 1990

The Journal of Cell Biology

300

190

View full text Add to dashboard Cite

show abstract

“…A change of this kind could explain the observation that in transferrin three protons are released for each Fe3+ ion bound (probably from deprotonation of the bicarbonate ion and two tyrosine ligands) but that only two protons are released for each Cu2+ ion bound (Gelb & Harris, 1980). It could also model the kind of changes that might occur if protonation of the CO2" anion is a first step in iron release, as postulated by various authors (Aisen et al, 1973;Williams & Woodworth, 1973;Sarra et al, 1990). Protonation would disrupt the anion hydrogen bonding in the diferric protein and movement of the anion and a change to monodentate coordination could lead toward breakup of the iron site.…”

Section: Discussionmentioning

confidence: 91%

Anion binding by human lactoferrin: results from crystallographic and physicochemical studies

Shongwe¹,

Smith²,

Ainscough³

et al. 1992

Biochemistry

View full text Add to dashboard Cite

The anion-binding properties of lactoferrin (Lf), with Fe3+ or Cu2+ as the associated metal ion, have been investigated by physicochemical and crystallographic techniques. These highlight differences between the two sites and in the anion-binding behavior when different metals are bound. Carbonate, oxalate, and hybrid carbonate-oxalate complexes have been prepared and their characteristic electronic and EPR spectra recorded. Oxalate can displace carbonate from either one or both anion sites of Cu2(CO3)2Lf, depending on the oxalate concentration, but no such displacement occurs for Fe2(CO3)2Lf. Addition of oxalate and the appropriate metal ion to apoLf under carbonate-free conditions gives dioxalate complexes with both Fe3+ and Cu2+, except when traces of EDTA remain associated with the protein, when hybrid complexes M2(CO3)(C2O4)Lf can result. The anion sites in the crystal structures of Fe2(CO3)2Lf, Cu2-(CO3)2Lf, and Cu2(CO3)(C2O4)Lf, refined at 2.2, 2.1, and 2.2 A, respectively, have been compared. In every case, the anion is hydrogen bonded to the N-terminus of helix 5, an associated arginine side chain, and a nearby threonine side chain. The carbonate ion binds in bidentate fashion to the metal, except in the N-lobe site of dicupric lactoferrin, where it is monodentate; the difference arises from slight movement of the metal ion. The hybrid complex shows that the oxalate ion binds preferentially in the C-lobe site, in 1,2-bidentate mode, but with the displacement of several nearby side chains. These observations lead to a generalized model for synergistic anion binding by transferrins.

show abstract

“…Its major recognition site appears to be found in the protein-bound 7V-asparagine-linked, mannose-rich oligosaccharide chains (Newman et al, 1982). The transferrin receptor is known to occur in nucleated red cells from chick embryos (Williams & Woodworth, 1973). Young & Aisen (1980) reported an association constant of 1.62 X 107 M"1 for the high-affinity transferrin site on rat hepatocytes.…”

Section: Discussionmentioning

confidence: 99%

Specific receptor for ceruloplasmin in membrane fragments from aortic and heart tissues

Stevens¹,

DiSilvestro²,

Harris³

1984

Biochemistry

View full text Add to dashboard Cite

Membrane fragments from aortic and heart tissues of immature chicks were observed to bind highly purified, 125I-labeled chick ceruloplasmin. The binding reaction exhibited a linear Scatchard plot for both tissues and showed for each an apparent dissociation constant (Kd) of about 10(-8) M. On the basis of Scatchard analyses, aorta contained 1.5 pmol of receptors/mg of membrane protein, whereas receptors in the membranes from heart tissue were at least 5 times more dense. The binding of chick ceruloplasmin to aorta membranes was trypsin sensitive and neuraminidase insensitive, and showed both saturation and reversibility. Various sialoglycoproteins in 500 molar excess had very little effect on the binding. The asialo derivatives of these proteins likewise did not inhibit the binding. Human ceruloplasmin was found to bind very weakly to the chick membranes. Asialo chick ceruloplasmin bound with the same efficacy as native chick ceruloplasmin. Heat-denatured chick ceruloplasmin, however, was very ineffectual in displacing native 125I-ceruloplasmin from the membranes. These studies provide the first evidence for a homologous membrane receptor for native ceruloplasmin in the plasma membranes of animal cells.

show abstract

The Interaction of Iron-Conalbumin(Anion) Complexes with Chick Embryo Red Blood Cells

Cited by 52 publications

References 22 publications

Role of the human transferrin receptor cytoplasmic domain in endocytosis: localization of a specific signal sequence for internalization.

Role of the human transferrin receptor cytoplasmic domain in endocytosis: localization of a specific signal sequence for internalization.

Anion binding by human lactoferrin: results from crystallographic and physicochemical studies

Specific receptor for ceruloplasmin in membrane fragments from aortic and heart tissues

Contact Info

Product

Resources

About