Transcobalamin II--cobalamin binding sites are present on rabbit germ cells.
Specific binding sites for rabbit transcobalamin II have been found on isolated adult rabbit germ cells. Scatchard analysis revealed a single class of binding sites for [57Co]cyanocobalamin-transcobalamin II with an association constant (Ka) of 1.3 x 10(10) M-1 and 700 sites per cell. Binding was reversible, saturable and calcium dependent. Electron microscope radioautography following incubation with iodinated transcobalamin II at 4 degrees C led to a detectable labeling mainly restricted to the plasma membrane.
Boukhzer
E
E
Laboratoire de Biochimie Nutritionnelle, INSERM U 308, Faculté de Médecine, Vandoeuvre-les-Nancy, France.
Ennya
A
A
Felden
F
F
Gérard
A
A
Nexo
E
E
Nicolas
J P
JP
Gérard
H
H
Guéant
J L
JL
D000818:Animals; D001665:Binding Sites; D002462:Cell Membrane / Q000378:metabolism; D004492:Edetic Acid; D005854:Germ Cells / Q000737:chemistry / Q000378:metabolism* / Q000648:ultrastructure; D007781:Lactoferrin; D008297:Male; D011817:Rabbits; D011956:Receptors, Cell Surface / Q000032:analysis*; D012710:Serum Albumin, Bovine; D013997:Time Factors; D014155:Transcobalamins / Q000378:metabolism*; D014168:Transferrin
D011956:Receptors, Cell Surface; D014155:Transcobalamins; D014168:Transferrin; C028176:transcobalamin receptor; D012710:Serum Albumin, Bovine; D004492:Edetic Acid; D007781:Lactoferrin